Talk:Earth/Archive 9

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Spinning globe

The new picture of a spinning globe is nice, but spinning way too fast. Now it's about one revolution per 2.5 seconds. Would look much better at once per 15 seconds (or more). −Woodstone (talk) 14:33, 27 May 2008 (UTC)

Of these two images I actually prefer the original (left):

• 
  Original image
• 
  Replacement image

The background provides a stable context for the image. The globe at right seems disturbing to watch as it is less smooth.—RJH (talk) 14:56, 27 May 2008 (UTC)

Okay -- thanks for the feedback!

I was originally going to do one above the "dawn-line" (at equinox), with the dark-side using NASA's "night lights" images.

In any case, I'll see if I can slow it down, keep some sky, work on the aesthetic, etc...

Wikiscient 15:22, 27 May 2008 (UTC)

Slower please - I feel ill. Also, there may not be a simple and intuitive way of representing the dark and light faces of the globe in the same animation. Creating them separately might be an idea if it's easy enough to do. Cheers, --Plumbago (talk) 15:39, 27 May 2008 (UTC)

Good point. The globe at left also provides some depth by including part of the shadow. The one on the right looks flat.—RJH (talk) 15:41, 27 May 2008 (UTC)

BTW, it's just that the one on the left (the original) seems so lacking in detail -- blurry, too dark, too much glare off the Sahara, etc.

Considering the size/resolution of NASA's "Visual Earth" images (on which both are based), it just seemed a shame to have to lose so much information to make a smooth animation gif with a reasonable (ie."Photoshop-acceptable") overall size...

I hear ya, though! Wikiscient 15:45, 27 May 2008 (UTC)

There is also a consideration of trade-off between detail and size. If there is too much detail, people will have issues trying to download the page because of the huge file. So it's a question of just what we're trying to show. Right now it just gives a general impression of rotation direction, an overall shape and a high-level view of the continents. Yes the image at right does have some positives, including the southern ice cap. But I also see some odd light blue patches that I can't quite make out because it's rotating so fast.—RJH (talk) 22:07, 27 May 2008 (UTC)

Just to be clear about the detail (eg. so that you can see that the light-blue areas represent shallower water) and so forth:

I've reduced the frame advance rate to one/sec (there are 24 frames, so that's "one hour/sec").
To get a "smooth" animation at a comparable spin rate, I'd need to have three or four times as many frames, so to keep the file size manageable I'd have to reduce the quality and/or dimensions down to that of the "original" (above).
But there does not seem to be much need for me to put much more work into this -- though I do think something incorporating a "lights at night" image would be neat, too!
Also btw the (unanimated & "flat") NASA images are available here.
Regards, Wikiscient 09:21, 28 May 2008 (UTC)

Sorry then, but that just doesn't work for me. It just isn't sufficiently smooth compared to the original and it provides no sense of depth.—RJH (talk) 15:30, 28 May 2008 (UTC)

Yes: no, of course I am not proposing it as a replacement anymore...

Just slowed the frame advance to show what would be nice, IF it could be both smoothly animated and as detailed...

Will let you know if I come up with some brilliant innovation that way, otherwise...

Cheers,

Wikiscient 05:07, 29 May 2008 (UTC)

I'm with RJH about the smoothness, but I've another question too. The NASA links that you provided above seem to show a globe where the Antarctic Peninsula is clearly visible. On the globe above it seems to be obscured by seasonal sea-ice. Any chance of using a sea-ice-free globe at your next iteration? It's perhaps not as realistic (since there's always some sea-ice), but at the moment the globe appears to show a strange composite of seasons. And, given global warming, cutting out the sea-ice makes your globe future-proof!  ;-)

On another unrelated note, the light blue regions on the globe may not be denoting shallow water but might simply be recording actual ocean colour. In shallow water regions, chlorophyll (and sediments, etc.) can create a strong signal, and the deep water regions of the globe show a palette that is independent of their depth (c.f. the brighter regions of the Southern Ocean). Anyway, that shouldn't affect your (sterling and much appreciated) plotting efforts, but when you label up the resulting globe you might want to explain the brighter blues that way. Cheers, --Plumbago (talk) 07:46, 29 May 2008 (UTC)

It might sound absurd

I know it might sound absurd but the Infobox Planet for Earth should or, most probably, it must contain an information about the human population. I wanted to know what is the human population on earth and I thought I could find it at the Earth's infobox but I did not. I never thougt to look at the World population article. Only after, I found out where it is. But I think that some people that had the same question as me, have searched the info on the Earth article. Anyway, it's a good idea to do a new section at the infobox, maybe with all the three values:

• 6,671,226,000 - 2007
• 7 bilion - predicted for 2013
• 9.2 billion - predicted for 2050

Tuloc (talk) 14:13, 29 May 2008 (UTC)

If there is interest in this, my suggestion is to use a separate infobox for the population, then place them both at the top and use {{FixBunching}}. If the box is displayed contracted, it could list multiple population stats for both past and future without impacting the page layout.—RJH (talk) 15:00, 29 May 2008 (UTC)

Earth-related topics

Placing the "Earth-related topics" infobox at the bottom has resulted in several attempts to create a redundant "See also" section. Should we:

1. Accept the redundancy between the two?
2. Move the contents of the "Earth-related topics" infobox back under "See also" and scrap the infobox?
3. Move the infobox back under the "See also" section header?
4. Keep deleting attempts to create a redundant "See also" section?

Thanks.—RJH (talk) 20:21, 30 May 2008 (UTC)

How about leave an HTML note in the last section of the article telling people to make sure they check the infobox at the bottom of the article prior to creating a See also section? That will probably discourage many of the people wanting to create the section. --Bobblehead ^(rants) 20:32, 30 May 2008 (UTC)

That might work: perhaps a single link under a "See also" section that points to the "Earth-related topics" infobox. Thus: Earth-related topics.—RJH (talk) 23:58, 31 May 2008 (UTC)

I think having the infobox expanded by default would also help; I didn't even notice it until I saw the edit summaries mentioning it's existence. An HTML comment isn't a bad idea, but it doesn't help readers. ASHill (talk | contribs) 21:41, 30 May 2008 (UTC)

Unfortunately I think the standard is to have it contracted. Plus it is inevitable that somebody will come along and contract it again.—RJH (talk) 23:58, 31 May 2008 (UTC)

Okay here's my thinking behind that section: I agree with the concerns about having a "See also" section too cluttered with too many links and making the navigation/info box at the bottom is a good idea. The problem with that is many users won't notice that navigation box and I'm sure many users find see also sections useful. The four links I added are all articles that contain a list of a lot more articles which is kind of like putting a navigation box (but more comprehensive) into one link. I think perhaps an article could be started titled "List of Earth-related topics" or "List of basic planet Earth topics" or something like that and all those topics in the navigation box could be listed in that article plus any other topics that are Earth-related. The only problem with that is it would share a lot of the same articles in the "List of Earth science topics" but that's not such a big deal. Then we could add that new link into the see also section and it would be like putting that navigation box there as you suggested. If people like this idea I could start making that article when I have the time or anyone else that's interested could. LonelyMarble (talk) 21:45, 30 May 2008 (UTC)

Other uses statement

I know this has been discussed before, but I'd like to make sure this is a satisfactory consensus as the "other uses" section at the top is still undergoing occasional revisionism. Which of the following is preferred for the "other uses" statement?

This (1):

This article is about scientific information on the Earth as a planet. For the Earth's geography, see World. For other uses, see Earth/Archive 9 (disambiguation).

or (2): {{three other uses|scientific information on the Earth|the Earth's geography|World|religious beliefs|creation myth}} or (3):

This article is about Earth as a planet. For the Earth's geography, see World. For other uses, see Earth/Archive 9 (disambiguation).

This article focuses on scientific information about the Earth. For religious beliefs about the Earth, see creation myth.

Thanks.—RJH (talk) 22:12, 30 May 2008 (UTC)

I like the first one the best, you can see my reasons behind this choice in the section below. Or if people don't like the use of scientific information like had been discussed in an old archive then this statement is fine too:

This article is about the Earth as a planet. For the Earth's geography, see World. For other uses, see Earth/Archive 9 (disambiguation).

Note that this wording is what the article had for many months without complaint until only little over a month ago, and I much prefer it than the current one.LonelyMarble (talk) 22:17, 30 May 2008 (UTC)

I thought of another option. If you really think the creation myth link is helpful why don't we put it at the top of the History section as a see also. One of the things that bugs me with it being at the top is it seems really out of place but if it was under the history section at least it would be in a more appropriate spot. LonelyMarble (talk) 19:29, 31 May 2008 (UTC)

Okay this is what I think the hatnote should be:

This article is about the planet. For the Earth's geography, see World. For other uses, see Earth/Archive 9 (disambiguation).

It is succinct, stardardized with the other planet hatnotes, and in the spirit of what a hatnote is, a navigation and clarification tool. If people insist on linking creation myth then it should be linked under the history section, it has no place in the top hatnote. LonelyMarble (talk) 23:32, 31 May 2008 (UTC)

I much prefer (2), as the topic of Earth's creation is a frequent subject for discussion on this talk page. I certainly don't see how it is out of place at the top, since the whole point of the note is to quickly redirect traffic. Hence, at present, we don't have a consensus. Does anybody else have an opinion on the matter? Thanks.—RJH (talk) 23:55, 31 May 2008 (UTC)

Hatnotes are for very specific things, they are primarily for navigation, which is why we link to Earth (disambiguation), and they are also for clarification which is why we link to World. Settling POV disputes and other stuff has abosolutely no places in hatnotes. No one searches for "Earth" if they want to know about creation myths or religious beliefs about Earth. It is also not necessary to mention anything about science in the hatnote. It is for navigation and clarification and nothing else. Including anything else would definitely be non-neutral in my opinion. LonelyMarble (talk) 00:02, 1 June 2008 (UTC)

Clearly the link is not going to settle anybody's opinion on the formation of the Earth, so I completely disagree with your conclusion. It is quite clear to me that the link is not going to change anybody's opinion on the formation of the Earth. To believe so is absurd. However, it is also clear that the religious aspects of the creation of the Earth is relevant to many visitors. So the link is appropriate.—RJH (talk) 00:21, 1 June 2008 (UTC)

I understand what you are saying but top hatnotes are for specific purposes. They are for people that search for "Earth" but don't want this article, which is why we are linking to Earth (disambiguation) and World. No one searches for "Earth" and expects to go to the "creation myths" article. You don't agree this link would be much more appropriate under the history section as a see also? This is the only section it would be relevant under other than the religious beliefs section where it's already linked, which is why I completely deleted it in the first place. This seems like clear case of WP:Undue weight to me. For a random example: why don't we mention "soil" at the top hatnote too because I assume people that search for "Earth" are far more likely to want the article "soil" than the article "creation myth", which is the sole purpose of the hatnote. LonelyMarble (talk) 00:31, 1 June 2008 (UTC)

Based upon Wikipedia:Hatnote, I accept your logic. I also believe that the statement, "For the Earth's geography, see World," falls under the category of "Linking to articles that are highly related to the topic", and so should be removed. In that case the note should approximately read, "This is about scientific information on the planet Earth. For other uses, see Earth (disambiguation)."—RJH (talk) 17:33, 1 June 2008 (UTC)

That's a good point. World does not need to be there either and it is linked in the first paragraph anyway. I will link "world" as a main article under human geography, which I'll do now, to help navigation. I agree that the top hatnote should be - {{about|scientific information on the planet Earth}} which will read

This article is about scientific information on the planet Earth. For other uses, see Earth/Archive 9 (disambiguation).

When I was reading through recent archives I noticed this discussion: Talk:Earth/Archive 8#"This article is about..." proposal, where two people objected to the use of "science" in the hatnote but I agree with what you said, the whole article is about scientific information and clarifying that in the hatnote is one of the uses of a hatnote so I have no problem using it. My argument on this issue was pretty much just based on the policies at Wikipedia:Hatnote because hatnotes are not technically part of article content so they should be as succinct and neutral as possible. So if you are in agreement you can change the hatnote to the above one. LonelyMarble (talk) 15:32, 2 June 2008 (UTC)

I agree, and I made the change suggested by RJH. ASHill (talk | contribs) 16:15, 2 June 2008 (UTC)

Scientific information wording

I feel that the "scientific information" wording is inappropriate. I, without having seen this discussion, changed the hatnote to read

This article is about the planet. For other uses, see Earth/Archive 9 (disambiguation).

In my opinion, we should not present more than this in the hatnote. If "scientific" refers to the natural sciences, then it is factually inaccurate as the "Cultural viewpoint" section and parts of the "Human geography" section refer not to natural sciences, but to social sciences. If "scientific" refers to the union of both hard and soft sciences, then it refers primarily to academic work and is redundant given that as Wikipedia is meant to be verifiable, the article should be using academic sources regardless.
I am similarly concerned that the wording is being used as a subtle disclaimer against creationists; while they are certainly annoying in multiple ways (the real concern being POV-pushing), this is not an excuse to include something in the article as a deterrent. Problematic additions can be reverted, and the authors of such additions educated about our neutral point of view. The neutral point of view issue is another problem that I have with the current wording of the hatnote. While I am agnostic and oppose dogma, it is equally important for the sake of NPOV that we not push our own views. It occurs to me that presenting the article as being composed of "scientific information" at very least implies a particular, science-favouring point of view – should not such implications be avoided? Nihiltres^{t.l} 22:10, 6 June 2008 (UTC)

In a certain respect, the use of "scientific knowledge" in this case is being used as a disambiguation, so as to clarify the purpose of the article. Obviously the article does not cover all aspects of the planet (which is a massive subject incorporating art, religion, philosophy, etc.), and so a very broad statement like "This is about the planet" is, in fact, unhelpful. By clarifying the scope of the article, the "hat-note" serves its purpose. If the use of the term "scientific knowledge" is indeed the problem, then what may be considered non-scientific aspects of the article could be readily relocated. The article is fairly massive as is, so a little judicious relocation may be in order. I would have no issue with relocating the cultural section to another page, and I have been contemplating just that once the section grew sufficiently large.—RJH (talk) 22:27, 6 June 2008 (UTC)

I changed this myself a few days ago without realising there was a discussion going on about it (sorry, I thought it was a fairly minor change). I agree with Nihiltres' rationale, and I think the best solution would be to just remove the two words from the hatnote. After all, if people really wanted to know about art on Earth, I can't imagine they would waste their time looking up the Earth article, and similarly for the other topics you mentioned. We don't bother including a similar disambig for all other scientific articles, and I don't see why we should be making an exception here. I do think that moving the cultural stuff to a new article (and leaving a see also link at the bottom of the page) is a good idea, provided others agree, and would be sufficient to deal with such non-scientific information contradicting the hatnote .. but I'd still feel scientific information was unnecessary. Ben (talk) 05:39, 7 June 2008 (UTC)

In the case of the hatnote, I'm neutral right now about whether "scientific information" should be in it or not, I'm not sure what the best wording is. However, about the culture section, I think it should be kept in. It is not that long and seems to me an important enough topic about "Earth" that it should be summarized in the article for a full scope of the subject. It's not like that section is singled out to Earth either, other of the planets have culture sections as well. And the study of culture is absolutely a scientific discipline, there's nothing in the article that's not scientific as it's all facts, facts about different beliefs is part of cultural anthropology as RJHall has said. LonelyMarble (talk) 15:56, 7 June 2008 (UTC)

If it becomes the consensus to remove "scientific information" from the note, then I guess I'll accept it. However, a thought I had was to consider changing it to "physical properties", which would give the page a tighter focus and shrink the size down a bit. But that would mean moving the culture and geography sections to other pages.—RJH (talk) 14:57, 9 June 2008 (UTC)

physical properties sounds like we're stating the obvious don't you think? With the hatnote saying this is about the planet, a link to the disambiguation, the see also section at the bottom and even the table of contents to a degree, I think we're covered - at least to the point that scientific information and physical properties aren't going to clarify things or help anyone any more than what these things do. I don't feel that strongly about it though if you really want it to stay there. Ben (talk) 02:53, 10 June 2008 (UTC)

By the same token, it is also blindingly obvious to say that the article is about "the planet". If the reader has not yet read the article, then it is not obvious that it would be about the physical properties (as opposed to culture, geography, history, art, mythology, &c.).—RJH (talk) 17:50, 10 June 2008 (UTC)

Leading with "This article is about the planet." is just a very quick clarification of what this article is about for someone searching for "Earth" but who did not want this article. That person could have been searching for a book named Earth, a song named "Earth", or anything else as listed at the disambiguation page we direct them to, where the article title for it could legitimately be simply "Earth". The hatnote does not need to clarify what exactly the article is about except for the most basic terms; it should be the job of the lead paragraphs to summarize and clarify what this article is exactly about. The lead paragraphs should, and I think do, make it obvious this article is about scientific information, and a look at the table of contents should make it clear it's mostly about physical properties. I also don't think this article needs too narrow and specific a description or needs to cut out any sections at the moment, like the culture or human geography sections. The article is not overly large in size (it's 98 KB in total size but only about 44 KB of that is readable prose), so I don't think there is a big need to cut its length. To conclude: for a succinct and neutral hatnote which is just there for navigation, this is probably the best wording: "This article is about the planet. For other uses, see Earth (disambiguation). LonelyMarble (talk) 21:02, 10 June 2008 (UTC)

Fair enough; at three to one that seems to be close to a consensus and there are no other objecting voices. I remove my opposition, although, for the record, I don't think the change is necessary or beneficial.—RJH (talk) 22:14, 10 June 2008 (UTC)

But the argument can be made that having "scientific information" is not necessary because it is redundant as Nihiltres said in the first post. And it is beneficial to remove so as to be succinct and neutral. I think anyone searching for creationism should know enough to search for creationism and not Earth. Editors that put in creationist weasel words in this article can simply be reverted for adding non-veriable information and weasel words. And I think it's pretty obvious these editors already know this article is about scientific information; my guess is editors with that POV are going to make those kinds of edits whether the hatnote dissuades it or not. LonelyMarble (talk) 22:36, 10 June 2008 (UTC)

Well I disagree and I thought that was made clear. Enough said.—22:52, 10 June 2008 (UTC)

Okay, I didn't mean to harp on it, and I know you disagree. I just didn't want you to be annoyed about the decision, but you're right, there's nothing more to say except for repeating ourselves. LonelyMarble (talk) 23:15, 10 June 2008 (UTC)

Request for MPH addition

A little ORBITAL CHARACTERISTICS addition for us simple people ? We're also orbiting Sol at 66,622.17 mph . . . —Preceding unsigned comment added by PFSLAKES1 (talk • contribs) 01:28, 3 June 2008 (UTC)

I think we're following the convention on scientific articles from Wikipedia:MoS#Conversions just to use metric. But it'd be nice if there were a mouse-over feature for unit conversions.—RJH (talk) 17:42, 4 June 2008 (UTC)

Too bad the contributors, likely all very familiar with the subject and therefore also very familiar with metric units and therefore in less need to use imperial/US units, decided not to convert to the latter. The article about the convention states that if it's a scientific article, and this is, then the contributors may choose whether to convert or not. But if you think about it for just a bit, it's obvious very many people reading the article are not like the contributors, that is, very familiar with the subject and comfortable working solely with metric units. Just think of the many kids working on reports, or k-12 teachers trying to gather many facts, yet either not yet knowing how to convert, or too busy with all the work that must be done elsewhere to convert all the units in the article. Please, don't decide how to present the article to scientists, they wouldn't necessarily bother with wikipedia, certainly wouldn't cite it, and are definitely not the only users of it. BeyondBeyond (talk) 03:37, 10 October 2008 (UTC)

Inconsistent density

Under Physical Characteristics the Earth's density is given as 5.5153 g/cm³. But right above it the mass is given as 5.9736 and the volume as 1.0832073 in the appropriate units. Given that 5.9736/1.0832073 = 5.5147, how was 5.5153 determined and why is it different? It's not a big difference, but I don't see why there should be any difference. --Vaughan Pratt (talk) 04:42, 5 June 2008 (UTC)

It looks like you've found one of the reasons that the infobox parameters should all be cited. Yoder (1995) gives:

• mass = 5.9736 × 10²⁴ kg
• volume = 1.08321 × 10¹² km
• density = 5.515 g cm^-3

These values are self-consistent, and they also match the "Earth Fact Sheet" values. I have no idea where the current values came from.—RJH (talk) 15:07, 5 June 2008 (UTC)

Average elevation of land

The source for "The mean height of land above sea level is 686 m" is an 1892 article, which cites its source as an 1888 article. An estimate I've seen in various places is 840 m, anyone have a trustworthy (and relatively recent) source for this quantity? --Vaughan Pratt (talk) 05:04, 5 June 2008 (UTC)

Do you have a source for the more recent estimate? it doesn't seem to be readily available.—RJH (talk) 14:57, 9 June 2008 (UTC)

I found this, but I have no idea how reliable it is (and it doesn't give any references). Ben (talk) 13:54, 13 June 2008 (UTC)

Maybe this is better? Ben (talk) 14:03, 13 June 2008 (UTC)

Thanks. From that I was able to back-track to an authoritative source:

• Sverdrup, H. U. (January 1, 1942). The oceans, their physics, chemistry, and general biology. Scripps Institution of Oceanography Archives. Retrieved 2008-06-13. {{cite book}}: Check date values in: |date= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)

On p. 19 it lists the mean land elevation of 840 m and the mean ocean depth of 3800 m. Those values come from an even older source: Kossina, Erwin (1921) "Die Tiefen des Weltmerres". So even this is pretty dated material. .—RJH (talk) 15:03, 13 June 2008 (UTC)

The end of life on Earth Contradictions 500 million years? 1 billion years? 1.9 Billion years?

I am a little confused as to what the information on this article and the Earth article says about the end of life on Earth. It says that in 900 million years all plants on Earth will die and in an additional 1 billion years all of the water on Earth will evaporate. Does this mean that in 1.9 billion years the Earth's ocean will evaporate? It is confusing because the sources say in 1 billion years the Earth's oceans will evaporate but the article says a billion years later, meaning 1 billion years after 900 million years the oceans will evaporate. So is it 1 billion years or 1.9 billion years that the Oceans will evaporate? Another thing is that it says also that in only 500 million years all life on Earth will die but this contradicts the place where it says that in 900 million years all plants will die and millions of years later on animals will die. I am so confused by these contradictions. Please help clarify this for me.Maldek (talk) 01:15, 19 June 2008 (UTC)Maldek (talk) 01:28, 20 June 2008 (UTC)

Here's the sequence:

• ~0.9 Gyr -- plants die.
• ~0.9 Gyr + several million years -- animals die.
• ~1.9 Gyr -- oceans evaporate.
• ~2.4 Gyr -- thermophile bacteria die; planet is uninhabitable.

I hope this helps.—RJH (talk) 17:36, 22 June 2008 (UTC)

The Sun becomes a Red Giant in 5.43 billion years.

The Sun is 4.57 billion years old and will spend 10 billion years as a Main Sequence Star before it becomes a Red Giant. Is it okay to change 5 billion years to a more accurate 5.43 billion years? Thank You.Maldek (talk) 04:35, 20 June 2008 (UTC)

10 billion years is just an estimate so it's doubtful it will be exactly 5.43 billion years until the Sun becomes a Red Giant. 5 billion years is just rounded off as is 10 billion because these are only estimates so there's no reason to go into more decimal places as that would just make it misleading in accuracy. LonelyMarble (talk) 13:35, 20 June 2008 (UTC)

See my reply in one of the (at least) two other places you made this comment. Short answer: no. ASHill (talk | contribs) 13:37, 20 June 2008 (UTC)

Sackmann et al (1993) says the Sun will spend 11Gyr on the main sequence. So I have to question the 5Gyr value. Perhaps there is a more recent source?—RJH (talk) 17:31, 22 June 2008 (UTC)

Schroder and Smith (2008) gives final main sequence at 10Gyr, then the Sun reaches the red giant branch tip after 12.17Gyr and the AGB at 12.3Gyr.—RJH (talk) 18:51, 23 June 2008 (UTC)

Those numbers are all essentially consistent with astronomical lore. I don't think any astronomer would argue with 10 Gyr as an approximate main sequence lifetime of the Sun, with about 5 Gyr down and 5 Gyr to go. Certainly, researchers continually improve the models, but I'm not sure worrying about the number at this level is worth our time here. I wouldn't object to any number in that ballpark (as long as we don't put 3 significant figures on it!).

My reading of Schroder and Smith is not a very precise determination of the end of the main sequence; they say "Around [10.0 Gyr], the evolution of the Sun will speed up" and it will become a red giant (p. 3, last paragraph of column 1 in the arXiv version). I think they have more precise calculations for the length of each of the post-main sequence phases of the Sun's evolution, which can give more precise relative times, but the main sequence lifetime of the Sun remains uncertain at the 10% level. (i. e. the Sun could reach the TRGB at 12.17 Gyr and the AGB at 12.3, or TRGB at 11.07 and AGB at 11.2). If they really mean that the main sequence lifetime of the Sun is precisely 10.0 Gyr, they have precious little explanation of how their code is so sure of that number; they also state no uncertainty on that 10.0 number. ASHill (talk | contribs) 19:24, 23 June 2008 (UTC)

Period of revolution of the Earth

Who is the moron that wrote "At present, Earth orbits the Sun once for every roughly 366.26 times it rotates about its axis." ?

The earth does absolutely not orbit around the sun each 366.26 days, it is 365. I edited the page, but someone removed my entry and blocked me from editing it back. —Preceding unsigned comment added by Sven Alexis De Varennes (talk • contribs) 04:06, 26 June 2008 (UTC)

The length of time in which the Earth makes one rotation around its axis relative to the fixed stars is called a sidereal day. It is slightly more than 23 hours and 56 minutes, and so is shorter than the usual solar day of 24 hours, which is the time it takes the Earth to make one rotation relative to the Sun. There are approximately 365.26 solar days and approximately 366.26 sidereal days in a sidereal year, which is the time it takes the Earth to revolve once around the Sun. Spacepotato (talk) 04:25, 26 June 2008 (UTC)

Life on Earth: misleading text on its begin and the "Cambrian Explosion"

In the first part of the "Earth" article it is stated that life on the planet began some one billion yrs ago. It is not true and, moreover, it is inconsistent with the info given in the same article below (about the first ancestor of all living organisms on the planet). One should keep in mind at least oldest stromatolites etc. or, maybe, oldest remnants of (suggested) bacteria...

I think you may be misreading it. The lead section says that life began within a billion years after the planet was formed, which is correct.—RJH (talk) 15:53, 29 June 2008 (UTC)

I am sorry for this mistake - indeed, the statement is correct. (TM)

It is not true that first multicellular organisms appeared in Cambrian! At least, the pre-Cambrian Ediacara fauna should be taken into account. As far as I remember, the "Cambrian explosion" is partly an illusion: a phenomenon caused by the fact that in Cambrian many animals started to produce carbonate skeletons, making them much more likely to be preserved as fossils. Cambrian absolutely not the begin of multicellular neither tissue-built animals (Eumetazoa).

Tomasz Mardal, Poland —Preceding unsigned comment added by 83.24.77.246 (talk) 10:59, 29 June 2008 (UTC)

Note that it says that "multicellular life forms began to proliferate", rather than saying they were formed during the Cambrian. Again I don't think the text as written is incorrect, and you may be misreading it.—RJH (talk) 15:53, 29 June 2008 (UTC)

IMO, the Precambrian multicellular, specialized forms of life (incl. the Ediacara fauna) should be at least shortly mentioned - without those the (brief) story of life on Earth seems to be misleading (the same regards oldest stromatolites). The statement that "the Cambrian explosion, when multicellular life forms began to proliferate" seems to be really not perfect, or doubtful, if one takes into account that numerous Ediacara fossils are supposed to precede several Cambrian animal groups evolutionally. I think it can't be definitely stated that the Late Precambrian Eumetazoa did not proliferate. (TM)—Preceding unsigned comment added by 83.24.7.109 (talk • contribs)

It is certainly possible that the text could be made clearer. However, one thing to keep in mind is that this section is written summary style. The messy details should really be covered on the linked History of Earth article.—RJH (talk) 16:21, 11 July 2008 (UTC)

I understand your point, but it is possible to avoid the doubtful sentence regarding the Cambrian explosion and the "proliferation" then without making the text much longer. At the moment, the text is misleading. The "summary type" of the text should not substantiate its such disadvantages. I am also of the opinion, that the spectacular and widely found Ediacara fauna could be (very briefly) addressed.

May I also suggest to add (very brief) info on the oldest Earth rocks known and oldest minerals (I gess, zircons preserved unchanged within metamorphic rocks), as well as the oldest remnants of life (incl. oldest Precambrian stromatolites).

By the way, the incorrect term "continental plate" is used at least twice in the section "Surface". First, this all stuff regarding the "tectonic plates" (or, better, "litosphere plates") should be moved to the previous section, regarding the plates themselves. Second, there is nothing like a "continental plate" - as you surely know, a specific plate of lithosphere may contain both oceanic and continental lithosphere. So, the term used, "continental plate" seems to be a remnant of the old Wegener's theory and should not appear in the Wikipedia at all. Koci Tata (talk) 21:10, 12 July 2008 (UTC)

Relative tilt of the Earth axis

When Earth orbits the Sun, the angle between the plan of the Earth terminator and the Earth axis is subject to continuous variation so that it equals zero at the equinoxes and reaches its (absolute) maximal value 23.4° at the solstices of June and December. This subtle oscillation of Earth axis around the terminator plan is the main cause of seasons.

When I added this statement (with 3D representations) to the Earth article (edit of 14:22, 20 June 2008), this one has been immediately deleted by Rracecarr. His argument of this deletion is this is misleading and oversimplified.

My question is: where misleading is in my description? Wikeepedian (talk) 13:13, 29 June 2008 (UTC)

By 'plan', do you mean plane? By the terminator I assume you mean the division between the illuminated and dark sides of the Earth? The oscillation in the Earth's axis it is because of precession and nutation, which are long-term effects. During the course of an annual orbit, this motion is not significant, so the axis continues to point to roughly the same location on the celestial sphere. Thus, I'll guess that to describe the axis as "oscillating" over the course of the year is perceived as misleading, and possibly confusing to a reader. It is instead the plane of the terminator that oscillates because of the orbital motion. But I'm not sure this is the best way to explain it.—RJH (talk) 15:49, 29 June 2008 (UTC)

Yes I mean plane of the Terminator (assumed as a circle on Earth that delimits the illuminated and dark sides of Earth). At the solstice of June the Northern hemisphere of Earth is tilted towards the Sun, so the angle between the Earth axis and the plane of the Terminator is exactly 23.44° (at the solstice of June the North pole is located in the illuminated side of the plane of the Terminator).

But at the solstice of December the Northern hemisphere of Earth is tilted away from the Sun, so the angle between the Earth axis and the plane of the Terminator is also 23.44°, but is reversed with respect to the plane of the Terminator (at the solstice of December the North pole is located in the dark side of the plane of the Terminator, we have the polar night).

At the equinoxes, the Earth axis belongs to the plane of the Terminator (the angle between the Earth axis and the plane of the Terminator = 0), this is why the day and night lengths are equal.

This explains easily what causes seasons. I never wrote about precession and nutation that are somewhat complex phenomenons. Wikeepedian (talk) 17:23, 29 June 2008 (UTC)

Sigh.—RJH (talk) 14:57, 30 June 2008 (UTC)

The edit was also uncited and largely duplicated material in Earth#Orbit and rotation. ASHill (talk | contribs) 18:07, 29 June 2008 (UTC)

Clarity

At the end, in the future section, it says that even if the sun where to remain constant life on earth would be killed because of decreased volcanic activity. How does this work (the linked article was not very helpful. Thanks, Brusegadi (talk) 13:46, 4 July 2008 (UTC)

IIRC, volcanism returns carbon to the atmosphere that has become buried in the Earth. (See carbon cycle.) Without the CO₂ gas, the temperature would drop below freezing and plant life would die off.—RJH (talk)

In the "Moon" section; the following text is found: "Some theorists believe that without this stabilization against the torques applied by the Sun and planets to the Earth's equatorial bulge, the rotational axis might be chaotically unstable, as it appears to be for Mars." Is there any supporting evidence or citations? This "fact" (chaotically unstable axis) is notably absent from the "Mars" article. Rusk42 (talk) 17:38, 11 July 2008 (UTC)

http://arxiv.org/abs/astro-ph/0111602v1 —RJH (talk) 22:42, 11 July 2008 (UTC)

I'd suggest changing that sentence to read:

"Some theorists believe that without this stabilization against the torques applied by the Sun and planets to the Earth's equatorial bulge, the rotational axis might be chaotically unstable, EXHIBITING CHAOTIC CHANGES OVER MILLIONS OF YEARS, as it appears to be for Mars."

Rusk42 (talk) 15:23, 15 July 2008 (UTC)

Sounds good to me (without the upper case lettering of course). Thanks.—RJH (talk) 19:07, 1 August 2008 (UTC)

American Units of Measure

I understand this may have been talked about before, and that the scientific articles use metric units for measurement, but I do hope that the community realizes that The United States of America does not use metric units for the hoi polloi (however frustrating it may be). Therefore, I do suggest that that American units of measure be added to this article when referencing the radius, circumference etc. There are over 300 million Americans, many of which read and contribute to wikipedia that do not know the conversions. I suggest that many Americans looking up "Earth" on wikipedia are in fact NOT scientists and therefore do need the American conversions. I am willing to edit them in if that is OK, I did not want to do so until I received some sort of consensus. Remember, metric does make more sense and is simpler, but unfortunately a very large percentage of the English speaking world population is dumbfounded by them. Thanks! —Preceding unsigned comment added by Jumacdon (talk • contribs) 21:11, 2008 July 7 (UTC)

Thanks for the offer. This has been discussed quite a bit on the different pages - the general consensus has been to keep science articles in metric. The metric system has been taught in US schools for at least the past 30 years - so nearly all of us have been exposed to it (though granted, many don't care for it) and the conversions are easily found. Besides that, we (people in US) actually make up significantly less than half of the English-speaking world population. But I'm willing to listen if others have a different opinion on the matter or alternate solutions. Thanks! PhySusie (talk) 19:51, 8 July 2008 (UTC)

Yes, many scientific articles tend toward metric only, but I think the reverse is true of general audience articles in that many report both the metric and imperial values. While one can certainly argue that this is scientific topic, I think "Earth" is of sufficiently wide interest to warrant the general approach, at least with respect to the numbers appearing in the body of the text. Therefore I would support adding parenthetical conversions to the body of the text where relevant. Dragons flight (talk) 20:01, 8 July 2008 (UTC)

I had the same impression Makewater (talk) 22:13, 9 July 2008 (UTC)

There is perhaps something to be said for Jumacdon's point of view. Of all the planetary articles, this one is probably of the most interest to a wider community than those seeking a purely scientific perspective. I was hoping we could keep the page focused on science, but that hasn't happened.—RJH (talk) 16:29, 11 July 2008 (UTC)

This article contains a lot of measurements, and it would be a shame to interrupt the flow of text with that many conversions in brackets (and in many cases that would mean nested parenthesis). While I agree that a more general audience probably visits this article, it's still only going to be a minority that benefits from the conversions (a minority that is introduced to the metric system during their school years no less). The MOS is fairly clear about it here, too. Ben (talk) 18:21, 13 July 2008 (UTC)

Funny, I feel the same way about the pronunciation inserts at the start of many articles.—RJH (talk) 16:29, 14 July 2008 (UTC)

I am still willing to edit the American Units if the consensus is that they are needed. I think we can just edit them into the side bar, but not in the body of text.Jumacdon (talk) —Preceding undated comment was added at 16:36, 1 August 2008 (UTC)

Actually my preference is to not add the American units to the infobox, as that will lengthen it quite a bit. But, personally I have no problem with conversions in the article body. I think there's a template around somewhere that will automate unit conversions.—RJH (talk) 18:33, 1 August 2008 (UTC)

The Future of Earth, persective 2

see: Earth#Future

I read the 'future of earth' section and believe it to be only tackling the issue from a solar perspective... in other words, the suggested pattern is that due to solar output increase, the Earth will eventually be baked dry. For the moment I will call this perspective 1; but there are two more elements (that I'm aware of) that must be considered.

Granted, the general future of the sun is fairly easy to predict, but it is not the only force active on Earth. Earth, itself, is an active force on Earth, and I don't see any mention of its affect over that very same future. It seems, rather, that the sun's affect is the only variable being considered.

What about the gradual cooling of the mantle and core? What about the eventual halt of tectonics, and the eventual end of vulcanism. I've heard estimates that both will have ended by the end of a billion years, and the results would mean a colder planet, whose water is either wholly frozen (in small part) on the surface, or (primarily) locked deep beneath the surface, in and under a crust too cold to force it back up again. Furthermore, declining vulcanism translates into less atmospheric replenishment/recycling and, finally, a cooling and less dynamic core would almost certainly mean a lessening magnetic field that is less and less capable of fending off the sun's touch... such that at the same time that geological replenishment of certain aspects of the atmosphere wanes, the top would be ever more sheared away and/or ionized. Even if the solar output increases, an internally 'less hot' planet with a thinning atmosphere may still swing climate toward 'icy' rather than 'steamy'

At any rate, what I'm asking for here is for folk who know more about this to persue the topic and help include it as part of the 'future' of the earth. My information on time scale is 2nd hand at best.

~Jeturcotte (talk) - July 13, 2008

My suggestion is to move the gritty details elsewhere, such as to Risks to civilization, humans and planet Earth. This page is already overly large, and ideally the future history section should be maintained in a summary style; covering only the most important facts in a compact manner.—RJH (talk) 17:09, 13 July 2008 (UTC)

Eeeeh... I have no reason to argue that this document isn't overlong; but 'Natural Changes to the Earth of the Future' really isn't the same thing as 'humans might not like it.' Seems like we may want a new topic for this. ~Jeturcotte (talk) - July 13, 2008 —Preceding comment was added at 19:09, 13 July 2008 (UTC)

Yes a scientific article about the Future of the Earth (that doesn't necessarily focus on the fate of humanity) could be a useful addition.—RJH (talk) 16:20, 14 July 2008 (UTC)

The Future of Earth, perspective 3

see: Earth#Future

Hokay then, on to the last variable I am familiar with as being likely to have a dramatic influence over the future and climate of the earth... namely, orbital and rotational changes.]

Again, as I said before, the 'future of the earth' segment only appears to be concerned with solar output changes, which are real enough... but the Earth and Moon are heading toward a probable orbital equilibrium that would have the moon some 40% further away and would also have Earth finally tidally locked to it... at which point a month and day would be the same length at some odd 42 contemporary days in length. Though the planet is cooling internally, and the atmosphere will thin as vulcanism wanes... what effect would it have on the Earth to have a daytime that lasts 21 now-days long?

Again, I'm asking that experts in this area help modify the Earth page to reflect these ongoing changes. It would be interesting to have a more complete scenario (or set of theories) based on all three variables, rather than JUST on solar output increases. Thanks!

~Jeturcotte (talk) - July 13, 2008

Again, summary style would be preferred. Thanks.—RJH (talk) 17:10, 13 July 2008 (UTC)

Cultural viewpoint - necessary?

It has come up a couple of times in the last month, but only briefly, so I wanted to start a focused discussion of whether or not certain sections should remain in the article. I think the article should tighten its focus on the planet, so we could potentially drop the Human geography, Religious beliefs, and Modern perspective subsections (at least/most?). I don't think many readers would come to this article looking for the information contained in those sections, for the most part, but there are some pieces of information that readers might specifically come to this article looking - e.g. the number of human inhabitants. I don't know how we could best deal with that, forcing it into another part of the article where it doesn't belong? modifying the hatnote again? should readers just be expected to know what other search terms to use? I'm really not sure. There is the 'Earth-related topics' template sitting hidden down the bottom, maybe we could use that to our advantage somehow?

Ben, your proposed split has been suggested before, but there were objections. Human geography makes sense on this article for obvious reasons; if there were human settlers on the other planets, those might also have similar sections. Note also that several of the other planet articles also have sections on human culture, including mythological beliefs.

That being said, there is an article called World that is (supposedly) focused on the human viewpoint. That might be a place to move some of that material, if it becomes the consensus. Thanks.—RJH (talk) 16:27, 14 July 2008 (UTC)

While I was writing this I was wondering if standardising the planet articles, regarding sections/subsections, has ever been discussed? I realise the Earth article would be the odd one out when trying to do something like that, but since it's related to this discussion, I thought I'd ask. Cheers, Ben (talk) 18:07, 13 July 2008 (UTC).

I expected to agree that those subsections could be dropped, but in reading through the article, I think they're actually quite brief, well-cited, and fit in well with the narrative of the article. The "Religious beliefs" section in particular is tightly focused on Earth itself and worth keeping here.

1. The "Modern perspective" section is the weakest of the three. In particular, the paragraph on the environmental movement is poorly cited: the one source, MIT Project on Environmental Politics & Policy, is of questionable reliability and doesn't obviously support the claims in the paragraph, although I don't think there's anything factually controversial in the paragraph. "Modern perspective" is also not a good section name: it doesn't really have any meaning. Perhaps rename the section "Images of Earth" or "Images from space" and delete/move the material in the section that doesn't fit with that subsection name?

   The material on the imagery seems too tactical in comparison to the remainder of the article. But the enviromental movement has a strong political following and is relevant to many readers, so it needs some sort of mention. Perhaps "Environmentalism" or "Environmental awareness" would be more apropros?—RJH (talk) 16:05, 15 July 2008 (UTC)

2. "Exploration and mapping" doesn't add much, and the relevant material might make more sense as a sentence in the "Human geography" section. ASHill (talk | contribs) 20:51, 13 July 2008 (UTC)

   I do think we need to make mention of the flat Earth vs. round Earth debate, as it was a major historical issue. The cartography paragraph could be removed without losing much. Perhaps the last two sections under "Cultural viewpoint" could be combined into a more compact single section about the changing human perspective?—RJH (talk) 16:05, 15 July 2008 (UTC)

3. A discussion of standardizing all planet articles probably belongs in a more centralized place (although I don't think standardization is likely to be helpful). ASHill (talk | contribs) 20:51, 13 July 2008 (UTC)

Is this necessary

"Home to millions of species,[8] including humans" everyone reading this knows that there are humans on earth with the possible exceptions of the incredible stupid and astronauts, i think it should be removed. 72.83.117.192 (talk) —Preceding comment was added at 20:39, 14 July 2008 (UTC)

This has been discussed many times, and the current version reflects consensus. See, most recently, Talk:Earth/Archive 8#Earth is the only place where Humans know that life exists., and the several sections following that thread. ASHill (talk | contribs) 20:52, 14 July 2008 (UTC)

Beating the dead horse some more

This is my first edit of any scale to this page, and I am not a scientist of any measure, but I have been noting all the debates over one of the opening sentences (guess which one); so, could we just put a little note at the top of page that states that this is written from a human viewpoint so that all the debates as to the wording of that sentence will stop? And include a link to whatever policy or guideline page states that all pages on Wikipedia are written by and for humans, if it exists. (Justyn (talk) 06:54, 27 July 2008 (UTC))

A hatnote should help readers, not help editors sidestep debates, I think. Ben (talk) 12:56, 27 July 2008 (UTC)

We can include an inline HTML comment in the source of the page beside the sentence, if that would help. It would be trivial to add <!--This sentence has uses a particular, consensus-picked perspective, and has taken a lot of debate to be settled. Before rewording it, please get consensus on the talk page.--> to help prevent unnecessary drama. I don't care either way, but this is the solution that you'd probably want. {{Nihiltres|talk|log}} 14:56, 27 July 2008 (UTC)

I think the current note at the top is the default standard, so a disclaimer seems unnecessary.—RJH (talk) 17:39, 27 July 2008 (UTC)

Image thrashing

The image arrangement of this page has been going through more thrashing lately. As a format improvement, I'd like to suggest modifying the table in the "Internal structure" section as follows:

Geologic layers of the Earth

Earth cutaway from core to exosphere. Not to scale.
Depth km	Component Layer	Density g/cm³
0–60	Lithosphere	—
0–35	... Crust	2.2–2.9
35–60	... Upper mantle	3.4–4.4
35–2890	Mantle	3.4–5.6
100–700	... Asthenosphere	—
2890–5100	Outer core	9.9–12.2
5100–6378	Inner core	12.8–13.1

(The information about location variation has been converted into notes.) Does this seem reasonable to everybody?

Also, in the "Tectonic plates" section, the location of the various plates is shown by the colored map. It seems reasonable therefore to remove the "Covering" column from the table in that section. The map could also be merged into the table (colspan="2") as per above.

Thanks.—RJH (talk) 15:56, 28 July 2008 (UTC)

There was no objection, so I went ahead and modified the text with a revised table.—RJH (talk) 18:34, 1 August 2008 (UTC)

Improperly sourced revisions

I reverted several edits made during the past day as they replace a valid reference with an unsourced remark and I could not access the one provided link. It is also unclear that the sigurdhu link is a reliable source. The site just looks like a generic account provider. By contrast, Michael Pidwirny is an associate professor at the University of British Columbia Okanagan. If there are better sources available that can confirm the changes, that would be great. Sorry.—RJH (talk) 17:52, 3 August 2008 (UTC)

Problem resolved. Please disregard.—RJH (talk) 20:18, 5 August 2008 (UTC)

a question...

"Earth is the only place in the universe where life is known to exist" Hasn't life been found on comets and whatnot? 69.183.4.168 (talk) 13:44, 10 August 2008 (UTC)

No. Signs of water have been found on Europa and Mars, at least, but no evidence of life. —Alex (ASHill | talk | contribs) 13:50, 10 August 2008 (UTC)

Life as defined by us.--Jakezing (talk) 01:42, 7 November 2008 (UTC)

Contradiction

Os it just me or do these two sentences contradict each other completely?

• Currently the total arable land is 13.31% of the land surface, with only 4.71% supporting permanent crops.

• Close to 40% of the Earth's land surface is presently used for cropland and pasture, or an estimated 1.3×107 km² of cropland and 3.4×107 km² of pastureland.

I didn't want to remove either one of them as I wasnt sure which one was correct... The Flying Spaghetti Monster! 20:46, 31 August 2008 (UTC)

Pasture land is often not arable, and crops aren't all permanent. —Alex (ASHill | talk | contribs) 20:56, 31 August 2008 (UTC)

So only 10% of all crops on Earth are permanent? I find that hard to believe... The Flying Spaghetti Monster! 21:17, 31 August 2008 (UTC)

The World Factbook entry on the World explains this nicely:

Land use:

arable land: 13.31%

permanent crops: 4.71%

other: 81.98% (2005)

Land use definition:

This entry contains the percentage shares of total land area for three different types of land use: arable land - land cultivated for crops like wheat, maize, and rice that are replanted after each harvest; permanent crops - land cultivated for crops like citrus, coffee, and rubber that are not replanted after each harvest; includes land under flowering shrubs, fruit trees, nut trees, and vines, but excludes land under trees grown for wood or timber; other - any land not arable or under permanent crops; includes permanent meadows and pastures, forests and woodlands, built-on areas, roads, barren land, etc.

Also, if 13.71+4.71= 18.02% of land is used for crops and 4.71 out of that is permanent that would be 4.71/18.02 = 26.14% of crops are permanent and 73.86% of crops are non-permanent. When you see what types of crops are classified as non-permanent: wheat, corn, and rice, this percentage looks about right. It is my understanding pastureland is specifically distinguished because it does not have crops so that 40% figure of 13% arable land and 26% pastureland does not contradict anything. LonelyMarble (talk) 21:58, 31 August 2008 (UTC)

Ah that was me confusing the term 'permanent' in this context. I thought it included all crops that are grown yearly ie corn, rice, wheat etc. Cheers for clarifying this. The Flying Spaghetti Monster! 10:23, 1 September 2008 (UTC)

Earth Day WP:TFAR

This article should be nominated at WP:TFAR next Earth Day. It is a core article and the only core WP:FA that has not been a WP:TFA from my quick glance.--TonyTheTiger (t/c/bio/WP:CHICAGO/WP:LOTM) 04:27, 1 September 2008 (UTC)

Sounds good to me, April 22 I presume. LonelyMarble (talk) 01:15, 6 September 2008 (UTC)

incorrect data

Please note that scientists have NOT proven that the Earth was formed billions of years ago. If you do have proof, please post it so that we all may see.24.74.160.28 (talk) 02:16, 15 September 2008 (UTC)September 13, 2008

Per Wikipedia:Talk_page_guidelines, "Article talk pages should not be used by editors as platforms for their personal views". Thank you.—RJH (talk) 16:02, 15 September 2008 (UTC)

Number format changes

I might as well post this now before another edit war gets started. User Kwamikagami made multiple changes to the numerical values in this article that do not appear to agree with the format at Wikipedia:MoS#Large_numbers. Some examples:

Before	After
152,097,701 km	152 097 701 km
1.0167103335 AU	1.016 710 333 5 AU

I think that such a change needs to be introduced via a MoS revision before it is introduced here. Wikipedia has its own standards that don't necessarily agree with particular ISOs. Any thoughts?—RJH (talk) 04:33, 20 September 2008 (UTC)

We have templates that automatically space fractional places, such as 1.016 710 333 5. Without breaks, "1.0167103335" is rather difficult to read. (This is especially true for things like "0.0000041 ± 0.0000007".) Although the MOS states that we're supposed to put commas after every three digits, would "1.016,710,333,5" or "0.000,004,1" be acceptable? I'd think that would just confuse people. kwami (talk) 04:40, 20 September 2008 (UTC)

Regardless of whether your statements are true or not, I would much appreciate it if you would work through the MoS revision process first before enforcing your own preferred formats. Personally I don't like the gap format, but I'll live with it once it is in the MoS. Thank you.—RJH (talk) 04:42, 20 September 2008 (UTC)

I started a MoS discussion thread at Wikipedia_talk:Manual_of_Style#Gaps_in_large_numbers. Thanks.—RJH (talk) 17:38, 23 September 2008 (UTC)

Summary-style "Cultural viewpoint"

What do you think about the idea of moving the "Cultural viewpoint" section to another page and replacing it with a summary? This approach is recommended on Wikipedia:Summary style for long articles.

For example:

Cultural viewpoint

Main article: Cultural view of the Earth

The name Earth was derived from the Anglo-Saxon word erda, which means ground or soil. It became eorthe in Old English, then erthe in Middle English. The standard astronomical symbol of the Earth consists of a cross circumscribed by a circle. Earth has often been personified as a deity, in particular a goddess. In many cultures the mother goddess, also called the Mother Earth, is also portrayed as a fertility deity. Creation myths in many religions recall a story involving the creation of the Earth by a supernatural deity or deities.

In the past there were varying levels of belief in a flat Earth, but this was displaced by the concept of a Spherical Earth due to observation and circumnavigation. The human perspective regarding the Earth has changed following the advent of spaceflight, and the biosphere is now widely viewed from a globally integrated perspective. This is reflected in a growing environmental movement that is concerned about humankind's effects on the planet.

With the appropriate citations, of course. Does anybody find this objectionable? Thanks.—RJH (talk) 21:55, 23 September 2008 (UTC)

I'm generally inclined to agree; that would certainly be consistent with policy and normal practice. That said, I feel like "cultural view of the Earth" is a bit of a contrived article topic: it seems like a dumping ground for stuff that gets added to the Earth article but doesn't really fit. (That may not be far from the truth.) I don't have a better idea at the moment, but might someone else? —Alex (ASHill | talk | contribs) 02:28, 24 September 2008 (UTC)

There are a number of "In popular culture" articles (which are somewhat similar in theme), so possibly the article could just be called "Earth in culture"? Most of the material in that section seems to be at least oriented toward culture. The exception might be the paragraph about cartography and surveying, which could be relocated to the "Human geography" section. I'm hoping that if the culture material is forked off to a new page, it will undergo more growth than it does at present (once the size limitations are removed). Thank you.—RJH (talk) 16:19, 24 September 2008 (UTC)

Infobox precision

I'm having a few minor concerns regarding the level of precision in the infobox. Wikipedia:MoS#Large_numbers says to avoid over-precise values where they are unlikely to be stable or accurate, or where the precision is unnecessary in the context. The orbital period is given as 365.256366 days, which corresponds to 365d 6h 9m 10.0224s. (Seriously, who has a watch accurate to one second per thousand years?) 365.256 days gives 365d 6h 9m 10s. Per the article, that number is also going to vary by 23μs per year, or 0.000023. So the current value will be off within a year.

There are also a number of fields with multiple values, but the level of precision of the values don't match. Example: 152,097,701 is nine decimals, 1.0167103335 is eleven. I think they should be consistent.—RJH (talk) 17:59, 24 September 2008 (UTC)

If my understanding of the following reference is correct:

• Simon, J. L.; Bretagnon, P.; Chapront, J.; Chapront-Touze, M.; Francou, G.; Laskar, J. (1994). "Numerical expressions for precession formulae and mean elements for the Moon and the planets". Astronomy and Astrophysics. 282 (2): 663–683. Retrieved 2008-09-27.{{cite journal}}: CS1 maint: multiple names: authors list (link)</ref>

then the eccentricity of the Earth undergoes variation equal to 0.00042 per thousand years, or ~10^-7 per year. That would suggest that 6 decimals is sufficient for long-term accuracy, rather than the 9 at present.—RJH (talk) 18:13, 27 September 2008 (UTC)

Astronomical practice is to quote the mean value of variable quantities only at the standard epoch, not for the year some publication is written. In 1976 the International Astronomical Union chose as its standard epoch, J2000.0 or 2000 January 1 12:00:00 TT, where the date is in the Gregorian calendar and the time is Terrestrial Time. This is still the standard epoch and probably will remain so until about 2025. Thus for all variable quantities, such as the orbital period (sidereal year), the value at J2000.0 was quoted 25 years ago, is still quoted, and will continue to be quoted until a new standard epoch is chosen. This value excludes all periodic terms such as nutation and planetary perturbations, so it is certainly not a measured value. Indeed, it cannot be a measured value because it is valid only for single instant in time, not for a whole year, thus it is an instantaneous year, an oxymoron. If this were a measurable quantity, an astronomer would use an atomic clock which has a typical error of one second in a million years, easily obtained via national radio stations such as WWV, which can indeed be used to synchronize some watches.

The sidereal year can be derived from the mean ecliptic longitude of Earth given in Simon (1994, p.675):

λ = 100°.46645683 + 1295977422".83429t − 2".04411t² − 0".00523t³, where t is the number of Julian millennia since J2000.0.

Noting that 1296000000" is 365250 days, the coefficient of t corresponds to 365.256363004193 IAU days of 86400 SI seconds each when limited to 15 significant digits as in the source. The IERS limited this to 12 significant digits in their Useful constants, 365.256363004 days. This article currently has chosen to limit it to 9 significant digits, 365.256363 days. All are equally valid because they all apply to a single instant in time, J2000.0. — Joe Kress (talk) 08:51, 28 September 2008 (UTC)

Fair enough. Thanks.—RJH (talk) 16:05, 28 September 2008 (UTC)

Orbit and rotation image

Earth's axial tilt (or obliquity) and its relation to the rotation axis and plane of orbit.

I'd like to suggest that we consider replacing the rotating Earth image in the above-named section with the illustration to the right. The latter seems more informative and it may help the reader better understand the text.—RJH (talk) 19:32, 29 September 2008 (UTC)

Looks much better to me. The rotating Earth image doesn't add much besides bandwidth. —Alex (ASHill | talk | contribs) 01:58, 1 October 2008 (UTC)

Etymology

Etymology: Middle English erthe, from Old English eorthe; akin to Old High German erda earth, Greek era. Date: before 12th century earth. (2008). In Merriam-Webster Online Dictionary. Retrieved October 6, 2008, from http://www.merriam-webster.com/dictionary/earth Pawyilee (talk) 12:11, 6 October 2008 (UTC)

Earth_in_culture#Etymology. —RJH (talk) 14:48, 6 October 2008 (UTC)

Moons

There are 7 moons —Preceding unsigned comment added by 84.67.160.50 (talk) 17:57, 6 October 2008 (UTC)

Indeed. Care to clarify?—RJH (talk) 19:35, 6 October 2008 (UTC)

Are asteroids moons?--Jakezing (talk) 23:43, 9 October 2008 (UTC)

Only if they orbit something larger, as with Phobos and Deimos orbiting Mars. kwami (talk) 23:53, 9 October 2008 (UTC)

Though one is getting farther away and the others gonna come crashing into mars. is the ISS a moon? how bout all the satelites we put into orbit? can we consider that giant black hole a moon?--Jakezing (talk) 23:55, 9 October 2008 (UTC)

The ISS is an artificial satellite. 'Moon' normally means a natural satellite. There is no black hole. kwami (talk) 00:06, 10 October 2008 (UTC)

Moon is synonymous with natural satellite, mystery solved. LonelyMarble (talk) 01:19, 10 October 2008 (UTC)

... idiots?--Jakezing (talk) 03:03, 10 October 2008 (UTC)

Either explain what you still don't understand or stop the BS. LonelyMarble (talk) 03:09, 10 October 2008 (UTC)

When did i ever say i didn't understand anything?--Jakezing (talk) 04:15, 10 October 2008 (UTC)

Jakezing, your behaviour is becoming increasingly inappropriate for a wikipedia talk page. Please take a look through Wikipedia:Talk page guidelines and Wikipedia:No personal attacks. Thank you.—RJH (talk) 16:30, 10 October 2008 (UTC)

Earth's Adjectives

I think that the word "Earthling" is also appropriate as an adjective. What are your thoughts? Fireleaf (talk) 21:29, 10 October 2008 (UTC)

Apparently Earthling has a valid meaning in a religious context, so that seems reasonable.[1]—RJH (talk) 18:20, 11 October 2008 (UTC)

On second thought, Earthling is not an adjective so I don't think it would be appropriate. Sorry.—RJH (talk) 15:56, 15 October 2008 (UTC)

Longitude of ascending node

Can someone explain to me why the longitude of the ascending node is not zero? Isn't the ascending node the same as the vernal equinox and isn't the vernal equinox at longitude zero by definition? Thanks for any help. PAR (talk) 10:42, 20 October 2008 (UTC)

An equinox is a property of the tilt of the Earth's axis, just as the timing of summer and winter are controlled by the tilt and not by orbital position. The ascending node position is property of the orientation of Earth's orbit. There is no reason they have to be related at all. They are close for the Earth, but that is coincidental. Dragons flight (talk) 11:10, 20 October 2008 (UTC)

Hi - thanks for the reply. Im still baffled tho - Looking at the article on the orbital nodes, it says that heliocentric orbits use the plane of the ecliptic as the reference plane for determining the nodes. I would say the earth's orbit is not inclined at all (inclination=0) and thats borne out by the value in the Earth article. So really, there are no nodes, ascending or descending. The article on the longitude of the ascending node says "For non-inclined orbits (with inclination equal to zero), Ω is undefined. For computation it is then, by convention, set equal to zero".

But ok, maybe it should be the earths equatorial plane that is used as the reference. If this is the case, then, according to the same article, the first point of Aries is the origin of longitude, which is just the vernal equinox, the point at which the sun lies on the earth's equatorial plane, which would also be the ascending node, since the nodes are where the orbital and reference planes intersect. If that is the origin of longitude, then the longitude of the ascending node is again, zero. Im sure I'm missing some simple point, but I cannot find it. PAR (talk) 03:46, 21 October 2008 (UTC)

Article issues

I have just began careful reading of this article and I've already noticed some major problems:

• Age of the Earth - 4.54 billion years ago - there is no uncertainty error given as shown in sources, also it's different than the value given in the article History of Earth
  • Okay, we can add an uncertainty value. However, the age in History of Earth is not properly sourced, so I believe that is not a valid concern for this article.—RJH (talk) 16:40, 3 November 2008 (UTC)
    • Cool. Two sources provide uncertainty value as plus/minus 1%. Would "4.54 ± 0.05 billion years ago" be okay? History of Earth article should be taken care of though, as there is link to it right in the first section of this article. That inconsistency can definitely be confusing to the reader.--Adi4000 (talk) 04:08, 4 November 2008 (UTC)
      • Yes that seems okay. Planet formation took at least 10 million years and possible up to 100 million, so I think the value is always going to be a little fuzzy. The 4.6 value may come from some sources that list 4.57 billion years, followed by rounding. Personally I don't think they're all that different.—RJH (talk) 17:25, 4 November 2008 (UTC)
        • I think this has been addressed. I left a message on the Age of the Earth discussion page regarding the 4.6 value.—RJH (talk) 23:23, 8 November 2008 (UTC)
• History of Earth - the "earliest known continent" is in conflict with Vaalbara article.
  • "earliest known supercontinent"; there's a difference between continent and supercontinent. It is already referenced.—RJH (talk)
    • Sorry, I meant supercontinent. The need for reference referred only to that phrase. I have read it and didn't find anything about "earliest known". Quite the opposite, it states: there is general acceptance of the existence of the supercontinent Rodinia about one billion years ago. Another supercontinent, variously termed Nuna or Columbia, is thought to have amalgamated about 1.8 billion years ago. Two others, Kenorland and Ur, are believed to have assembled 2.5 and 3.0 billion years ago. I'd suggest mentioning Vaalbara based on the refs given in the article about it, or changing the phrase to "one of the earlier".--Adi4000 (talk) 04:08, 4 November 2008 (UTC)
      • Okay sorry, my misunderstanding then. Vaalbara looks to be hypothetical at this point. Probably best just to add "One of the earliest..." then, as you suggested.—RJH (talk)
        • Done.—RJH (talk) 23:23, 8 November 2008 (UTC)
• Ref #24 - Ward and Brownlee (2002) - I'd like to verify this and don't even know if it's a book or an article as there's no title.Forgot about Bibliography :)--Adi4000 (talk) 08:55, 3 November 2008 (UTC), the book states big things and there are no pages given when referenced. Having to look through the entire book is not appropriate for FA.
  • I'll need to get it out of the library again, unless somebody has a copy.—RJH (talk) 17:11, 3 November 2008 (UTC)
    • Selected parts are available here.--Adi4000 (talk) 04:08, 4 November 2008 (UTC)
      • I added a second ref, so this is done. I'll take care of the pages issue later.—RJH (talk) 23:23, 8 November 2008 (UTC)
• Ref #17 doesn't have Cite template & lacks info.
  • It was an improper reference to Yoder (1995). I updated it.—RJH (talk) 17:02, 3 November 2008 (UTC)
• I think there should be an extra paragraph in the Introduction about the influence on culture, something about modern perspective (for ex. exploration of Earth from space) and the ultimate future of the planet. Also, there is practically no mention about exploration of Earth from space in the Cultural viewpoint section and "Earth in culture" is hardly an appropriate title for it.
  • Yes, the lead should cover also the habitability section. The cultural viewpoint section is written summary style, and I think a two sentence summary is fine. What else would you add? More than that seems like fluff. I disagree about the "Earth in culture" remark, but that is a different article and so irrelevant to this page's status.—RJH (talk)
    • Done.—RJH (talk) 23:23, 8 November 2008 (UTC)
• The biggest problem - one little paragraph on Internal Structure section. I don't think that gives due weight as required in featured articles, since "Orbit and Rotation" is about 8 times bigger. I know there's a separate article but Orbit and Rotation provides 2 separate links. Also, this is much less than "Internal Structure" sections of other planets, such as Jupiter, Mercury, etc.
  • Well, "Internal Structure" is actually two paragraphs plus a table and plot. But the real problem (to me) is that "Orbit and Rotation" has undergone bloating since this article went FA. I think that section should be sub-divided.—RJH (talk)

I'll update as I find more.--Adi4000 (talk) 07:59, 3 November 2008 (UTC)

Thanks for the feedback.—RJH (talk) 16:49, 3 November 2008 (UTC)

Thanks for answering. I am actually in the process of translating this article to another wiki, that's why I'm paying so much attn. to its accuracy. These issues aside, nice article :)--Adi4000 (talk) 04:08, 4 November 2008 (UTC)

I believe I've address your concerns about this page. Thanks.—RJH (talk) 23:21, 8 November 2008 (UTC)

polution of ozonelayers

polution of ozonelayer occered because of old refrigirators,the rays of the refrigirators can easyily defeat ozone. —Preceding unsigned comment added by 117.200.129.115 (talk) 13:59, 3 November 2008 (UTC)

Expanded lead

Per the above review, I put together a tentative fourth paragraph for the lead. Does anybody have issues or concerns with the wording? Perhaps somebody has a better proposal?

The physical properties of the Earth, as well as its geological history and orbit, allow life to exist on the planet. Both the mineral resources of the planet, as well as the products of the biosphere, contribute resources that are used to support a global human population. The inhabitants are grouped into about 200 independent sovereign states, which interact through diplomacy, travel, trade and military action. Humans cultures have developed many views of the planet, including personification as a deity, a belief in a flat Earth, and a modern perspective of the world as an integrated environment that requires stewardship. Humans first left the planet in 1961, when Yuri Gagarin reached outer space. The world is expected to continue supporting life for another 1.5 billion years, after which the rising luminosity of the Sun will eliminate the biosphere.

There may be a need to modify the second paragraph accordingly. Thanks.—RJH (talk) 21:44, 3 November 2008 (UTC)

Support - according to FA Criteria, lead section should summarize the topic and prepare reader for details, and up to now, these later sections were treated as if they've never even been there.--Adi4000 (talk) 04:24, 4 November 2008 (UTC)

A recent picture to replace the blue marble image would be really nice, since we now have the technology to observe the Earth with highly advanced cameras. While that older image is recognized (it should be moved to a more appropriate section), it is 2008... we at Wikipedia could be help promote a new image for the next generation now in school. My specialty is not images though, so someone with that expertise might be able to accomplish this if we have consensus. This is one of the most important leads in all of Wikipedia. Two examples are listed below: All Is One (talk) 16:25, 5 November 2008 (UTC)

"View of the Earth as seen by the Apollo 17 on December 7, 1972.

Satellite photography can be used to produce composite images of an entire hemisphere... a 21st century view.

It sounds like you are arguing to make a change for the sake of change. The current image is of excellent quality, fine aesthetics and is an accurate representation. A higher resolution camera is not going to improve the image quality, given that we're only displaying it with a width of 240px. As far as I know, bits don't rot: the image is as good now as the day it was published. Thus I'll have to disagree with your suggestion. Sorry.—RJH (talk) 19:08, 5 November 2008 (UTC)

Yes the second image is nice, even though it's a composite rather than an actual picture. It's a matter of personal preference, I guess. We can probably use both in the article. Note, however, that the image is so huge (3000 × 3000 pixels) that it takes many minutes to scale it down to 240px. Somebody needs to resize it for use.—RJH (talk) 16:42, 6 November 2008 (UTC)

The second image, from 2000, is a false-color composition based on GOES imagery. (Don't the colors just look too bright to anyone else?) Since 2002, NASA composites have been using true-color MODIS imagery. Oppose the use of the false color image. Dragons flight (talk) 23:21, 8 November 2008 (UTC)

I agree that a true-color image would be really nice in the article. Ideally, this would be a view of the Mid-Atlantic showing North America and Europe, since we are using the image on English Wikipedia. This view would show some daylight and night time, possibly some city lights. My thoughts with this are to illustrate what Earth truly looks like from space, human presence included (we are part of the natural environment and have transformed Earth to look like that). The composite photo would be a possibility for a more scientific section, just an example though. Maybe we could have the blue marble photo and a true-color photo in the lead to show our advancement in technology with Earth observation... All Is One (talk) 15:46, 9 November 2008 (UTC)

The current image is a true color image. Might I suggest first adding any such images to http://commons.wikimedia.org/wiki/Earth ? Thanks.—RJH (talk) 17:55, 23 November 2008 (UTC)

Oxydizing Atmosphere

The article claims that the atmosphere is oxidizing due to the escape of the rudcing element hydrogen. Although this might be considered true in some tortuous sense, free oxyegen is generally considered to be a result of photosynthesis - and ideed, the reference for the se3ntence about reducing and oxydizing atmosphere states this clearly. The sense the escape of free hydrogen could be considered to lead to free oxygen is that if there were more hydrogen in the biosphere, there might be enough to reduce all the oxygen (that is oxidize the hydrogen) to form water.

151.195.3.100 (talk) 20:53, 5 November 2008 (UTC)

I think that the point being suggested is that, if he atmosphere had a solar abundance of free hydrogen, the oxygen being generated through photosynthesis would be locked up into water (perhaps by alternate life forms). Thus it would not be oxidizing. If photosynthesizing life could somehow evolve in the atmosphere of Jupiter, it would not create an oxydizing atmosphere because most of the hydrogen has been retained.—RJH (talk) 22:44, 5 November 2008 (UTC)

The light reactions of photosynthesis split water into H⁺ + O₂ + energy. That O₂ usually enters the atmosphere. The dark reactions take H⁺ + energy + CO₂ to build hydrocarbons + H₂0. However, if every O₂ that enters the atmosphere were allowed to break down the same hydrocarbons it created, either via oxygen-mediated metabolism or burning, then there would be very little net accumulation of oxygen. To move the Earth as a whole from a highly reduced initial state to the highly oxidized state we have today, so the argument goes, you have either sequester or remove a substantial abundance of reducing agents in order to create an imbalance that pushes the system toward oxygen accumulation. A common view is that this occurred in large part via the removal to space of free hydrogen from the pre-oxic atmosphere (e.g. [2]). By comparison, in the modern world most hydrocarbons are ultimately degraded by oxygen. Of the ~60 GtC bound in hydrocarbons by plants each year, only about 0.02 GtC / yr is ultimately buried in geologic deposits; the remaining 99.9% is eventually oxidized to feed some form of life. So the modern world is in balance such that oxygen is neither accumulating nor decreasing in the atmosphere, but rather the same amount is being created as is being consumed (to rough approximation, and ignoring the bias created by fossil fuel burning). To accumulate oxygen you need an instability such that some of the oxygen released is not used to break down the other resulting compounds. Though photosynthesis is the source of oxygen, the large scale accumulation of oxygen also required a reduction in the availability of reducing compounds. That instability may have been provided by the escape of hydrogen. Dragons flight (talk) 23:43, 5 November 2008 (UTC)

Sol-3

Sol-3 redirects here. Could some discussion on this term be included in the article? __meco (talk) 12:34, 8 November 2008 (UTC)

The explanation of that name was already there in the first sentences, stating it is the 3rd planet of the Sun. Added the name in the list (no link, which would be circular). −Woodstone (talk) 16:15, 8 November 2008 (UTC)

Sol-3 is a neologism; at best it may have been used in a sci-fi context. It is not a common name for the planet. Sorry but I removed your edit per Wikipedia:Avoid neologisms. It needs further discussion before it can gain acceptance.—RJH (talk) 22:47, 8 November 2008 (UTC)

Sol is a scientfic name for the sun; sincecalling it "the sun" wouldn't work and would lead ot confusion once we have people in other star systems who would call their star "the sun". It also is the name of the solar system ussualy. logical deduction shows SOL-3 is another name, a scientific name for earth. Mars is therfor SOL-4, jupiter 5, and pluto Sol-... i don't know probably something like SunbSol-2.--Jakezing (talk) 21:42, 9 November 2008 (UTC)

Actually no, "The Sun" is the proper name for precisely one star. The proper names for other stars are things like Betelguese, Beta Pegasi, and Alpha Centauri. Strictly speaking, calling any of those the sun would be wrong. Whether colonists might one day choose to refer to them as "The Sun" as well is back in the realm of sci-fi, and not something we are going to indulge here. Scientists use name, e.g. Mars, Jupiter, Pluto, and not silly designations. Dragons flight (talk) 22:53, 9 November 2008 (UTC)

Yesd but from a scientific standpoint the name for the planets besides the traditional onesl; is the scientfic name for our star with the number after it. Our sun is no different from all the other stars, it just happens to have a planet with life as we define it.--Jakezing (talk) 03:23, 10 November 2008 (UTC)

You'll need to find valid scientific or otherwise solid references that use "Sol-3". Otherwise it is something made up and doesn't belong here. See Wikipedia:No original research for example. Sorry.—RJH (talk) 16:05, 10 November 2008 (UTC)

No, the scientific names are those endorsed by the IAU (Mercury, Venus...), while the IAU does not recognize the sci-fi naming conventions. "Sol-3", etc. are not scientific names for our planets. For that matter "Sol" is not an officially recognized name for our star, and has no more standing than "Helios" (the equivalent Greek), or any other translation. Dragons flight (talk) 17:21, 10 November 2008 (UTC)

Proposed modification to the 'History' section

I'd like to propose a modification to the 'History' section that will incorporate the 'Future' section. Right now 'Future' seems stuck out on its own, past the culture and geography information, and I think it would provide better article flow by being included with the history. Here's what I'm suggesting:

• The first part of 'History' will cover the non-biological information. It would include Paragraph 1, the first sentence of paragraph 2 and the fourth paragraph ("Beginning with almost no dry land...").
• A section titled 'Evolution of life' would cover the biological information, which is the remainder of the 'History' section, plus the ice ages.
• A second section would result from the merger of the 'Future' section.

Any thoughts or concerns about this? Thank you.—RJH (talk) 22:51, 10 November 2008 (UTC)

I don't see how you can make the words future and history merge.--Jakezing (talk) 22:52, 10 November 2008 (UTC)

Well the section could either be renamed to 'Life span', or the sub-section changed to 'Future history'. But the latter may conflict with the MoS guidelines.—RJH (talk)

Upload this

Will someone stop protecting this page so we can upload earth.jpg from Yahoo! Images?66.72.201.167 (talk) 17:04, 23 November 2008 (UTC)

Unfortunately this page is currently protected because the amount of plebish vandalism greatly outweighed the benefit of leaving it open. But there is nothing to stop you uploading an image to wikipedia, or even to the commons. Alternatively you could post the link and let us see what we're missing. =) My concerns are that the current article is already image rich, and adding more may mess up the formatting, make it slower to download and perhaps not add anything new. But there's always room for improvement.–RJH (talk) 17:49, 23 November 2008 (UTC)

Just upload the image.66.72.201.167 (talk) 18:41, 23 November 2008 (UTC)

That would be a no.—RJH (talk)

Scientific evidence shows...

At ptesent, the lead includes the following statement:

Scientific evidence indicates that the planet formed 4.54 billion years ago, and life appeared on its surface within a billion years.

However, I think that the word "shows" would be a stronger, less passive wording than "indicates". Thus:

Scientific evidence shows that the planet formed 4.54 billion years ago, and life appeared on its surface within a billion years.

Within the context of scientific investigation, I'm not aware of any significant controversy about the age; at least in terms of the order of magnitude. (This issue seems to have been settled about a century ago.[3]) Thus I think the stronger wording is warranted, under the proviso that this is the scientific viewpoint. Would anybody find this modification objectionable? Thanks.—RJH (talk) 18:49, 24 November 2008 (UTC)

Why not just "The planet formed 4.54 billion years ago, and life appeared on its surface within a billion years"? It reads nicely, and it doesn't sound like a ", but, x indicates otherwise" has been striped off the end. Ben (talk) 19:27, 24 November 2008 (UTC)

Personally I would be fine with that, but I'd like to have a clear consensus here that we can point to in the future.—RJH (talk) 23:13, 24 November 2008 (UTC)

Good luck with that vote; nobody here.--Jakezing (talk) 04:00, 26 November 2008 (UTC)

Well technically it's not really a vote. =) But for a widely read page like this, I think that if nobody has an objection within a week then it can probably be taken as consensus(?). If there is an objection later than we can just direct them to the Age of the Earth article and let them hash it out there. We could also add a note to this page explaining the age is based on radioactive dating, blah, blah, blah.—RJH (talk) 16:12, 26 November 2008 (UTC)

I agree with Ben. "Scientific evidence indicates/shows" is redundant and unnecessary. You could put that same line before a lot of things in this article or any scientific article, I don't think the qualifier is needed. Plus, the 4.54 billion number is linked to the age of Earth article for anyone interested. LonelyMarble (talk) 21:07, 26 November 2008 (UTC)

I too support the removal for all those reasons, and will take it out. --an odd name 18:40, 27 November 2008 (UTC)

Consensus is achieved.—RJH (talk) 23:21, 28 November 2008 (UTC)

Amount of habitable land

I see the problem with this sentence in Human Geography:

It is estimated that only one eighth of the surface of the Earth is suitable for humans to live on—three-quarters is covered by oceans, and half of the land area is either desert (14%),[122] high mountains (27%),[123] or other less suitable terrain.

1/8th, which I believe is based on proportions given in the second part of the sentence (1/4 land area * 1/2 suitable land = 1/8th), based on sources, is incorrect. It implies that humans don't settle, for ex. in high mountains. Source [123] says: Mountain environments cover some 27% of the world’s land surface, and directly support the 22% of the world’s people who live within mountain regions. I've been trying to find a source online that approximates amt. of suitable land for humans, unfortunately, I wasn't able to. --Adi (talk) 18:45, 27 November 2008 (UTC)

Perhaps the wording needs to be modified to relate habitability to human population density? Alternatively, it could say something about potential agriculture usage. Or possibly a combination of the two.—RJH (talk) 17:48, 3 December 2008 (UTC)

Terrain variation

The following sentence seems both vague and relative. I think the same sentence can be applied to the Moon and any of the other terrestrial planets.

The Earth's terrain varies greatly from place to place.

Do we need this statement? If so, could you suggest how to make it more useful? Thanks.—RJH (talk) 17:44, 3 December 2008 (UTC)

I don't think we need to mention that at all. Simply looking at a topographical map of Nebraska and Colorado... or Europe and Africa will show this; I mean it is pretty obvious that it varies greatly from place to place where we have mountains 20+ thousands of miles high; and trenches equally as low. It's simply redundant to state that fact... or we could put a Citatin needed tag next to it and see what happens either way.--Ssteiner209 (talk) 13:45, 8 December 2008 (UTC)

The Earth actually has quite a smooth surface.[4] -Atmoz (talk) 18:40, 8 December 2008 (UTC)

If it had a smooth surface there would be less friction and a lot of bad shit would happen so i can't believe that.--Ssteiner209 (talk) 22:48, 8 December 2008 (UTC)

There is no need for vulgarity. I suggest reading Earth#Shape.—RJH (talk) 16:21, 9 December 2008 (UTC)

Land use

The sentence: "...total arable land is 13.31% of the land surface, with only 4.71% supporting permanent crops" doesn't correspond to its source (the CIA factbook) which states: arable land: 10.57% - permanent crops: 1.04% - other: 88.38% (2005).

The link redirects to the 2008 factbook. The data may have been revised.—RJH (talk) 16:18, 9 December 2008 (UTC)

Also, it is not clear how the next sentence: "Close to 40% of the Earth's land surface is presently used for cropland and pasture, or an estimated 1.3×107 km² of cropland and 3.4×107 km² of pastureland." relates to these figures. I have not access to the source given (the FAO Production Yearbook 1994). --Sir48 (talk) 15:11, 9 December 2008 (UTC)

I think the key word there is 'pasture', which may be non-arable. Again it may be some data that has since been removed. it would be nice if we had a more stable source, such as a journal article.—RJH (talk) 16:18, 9 December 2008 (UTC)

I had a similar discussion with another user about this in the archives here: Talk:Earth/Archive_9#Contradiction. That should explain the definitions. But the problem here is that the World Factbook figures for arable land and permanent crops has changed. When I made that comment in the archives less than four months ago it was the 13.31 and 4.71 figures in the World Factbook, now the figures are 10.57 and 1.04. The odd thing is not only does this change in figures seem a bit large (but maybe it's not I wouldn't know), but also the year was stated as 2005 for the old figures and it's still stated as 2005 for the new ones as well. The World Factbook has to be considered a reliable source though so maybe these numbers should be changed in the article, and it would be nice to find another collaborative source for these figures, especially one that has information on the other types of land like pastureland. LonelyMarble (talk) 00:08, 10 December 2008 (UTC)

Here's another observation, currently the table in Habitability is this:

Land use	Percentage
Arable land:	13.13%
Permanent crops:	4.71%
Permanent pastures:	26%
Forests and woodland:	32%
Urban areas:	1.5%
Other:	30%

If you add all those numbers up you get a percentage of 107.34. Now if you instead use the new numbers of 10.57 and 1.04 you get a percentage of 101.11. Note that I'm not sure where the pastures, forests, urban areas, and other figures come from. While the new World Factbook figures make the percentage much closer to 100, a good source for this information is obviously needed. LonelyMarble (talk) 00:20, 10 December 2008 (UTC)

Alright, after all that blabbering I came to the Food and Agriculture Organization of the United Nations official site. That is the same source used in the article (FAO Staff (1995). FAO Production Yearbook 1994 (Volume 48 ed.). Rome, Italy: Food and Agriculture Organization of the United Nations. ISBN 9250038445.), but apparently the source from the article uses figures from 1993. This site right here seems to contain all the information we'd need and it's updated to 2005: [5]. Only problem is it might take a little while to convert all the units and get the percentages correct. I'll attempt this some time in the future when I have more free time if no one else does it first. Here's the main site: [6], and I went to ResourceSTAT - Land for the link above. Anyone that wants to update these figures feel free. LonelyMarble (talk) 00:48, 10 December 2008 (UTC)

Thanks for finding that site. I looked up the data given for 2005 and found the following (unit for area: 1000 Ha = 10 km²):

Land use	Area (1000 Ha)	Caculated percentage
Total land:	13,013,475.40
Arable land:	1,421,169.10	10.92%
Permanent crops:	140,511,70	1.08%
Permanent pastures:	3,405,897.80	26.17%
Forests:	3,952,025.70	30.37%
Other:	4,092,972.40	31.45%
Total:		99,99%

This looks rather good to me and I suggest to use these sourced figures as basis for the texts of the article. (Please beware, the general disclaimer for the FAO statistics looks somewhat harsh...). --Sir48 (talk) 01:49, 10 December 2008 (UTC)

That works for me too. My suggestion is to add a bold-face caption to the table and apply the citation there. Thanks.—RJH (talk) 16:14, 12 December 2008 (UTC)

U/L Case?

The following appear in the article using both upper and lower case forms: North Pole, South Pole, Arctic Circle and Antarctic Circle. I think they should be consistently one or the other. Thanks.—RJH (talk) 16:12, 12 December 2008 (UTC)

They should all be in upper case. LonelyMarble (talk) 21:33, 12 December 2008 (UTC)

Alternative Names Section

How about a section that lists different cultures' alternative names. This is very Western-centric. 24.174.82.195 (talk) 22:40, 12 December 2008 (UTC)

Wikipedia is not a dictionary. Why would a list of non-English names be at all relevant to an English-language article, unless they are associated with particular cultural beliefs? On the other hand, cultural beliefs about the Earth can always be added to the Earth in culture article.—RJH (talk) 16:45, 15 December 2008 (UTC)

Scrolling problem?

Is it just me, or does this article seem to have lag issues with scrolling?—RJH (talk) 01:50, 10 November 2008 (UTC)

This IS big ass article.--Jakezing (talk) 03:24, 10 November 2008 (UTC)

Well whatever was causing the problem appears to have cleared up.—RJH (talk) 16:03, 10 November 2008 (UTC)

Had the same problem on the talk page back then as well. I think that it was the animated globe. Things got better after it was archived. ~ All Is One ~ (talk) 06:36, 19 December 2008 (UTC)

Question with orbital characteristics

how many is the earth Synodic period???but the moon Synodic period is know and it is result please yeah —Preceding unsigned comment added by 125.160.161.55 (talk) 08:38, 22 December 2008 (UTC)

Your question doesn't quite make sense.—RJH (talk) 17:03, 22 December 2008 (UTC)

The synodic period of a celestial object is the time it takes for that object to reappear at the same point in the sky, relative to the Sun, as observed from Earth. Generally, it is the time between conjunctions of the object with the Sun as observed from Earth. It is not applied to objects outside the solar system such as a fixed star. Thus in general the Earth cannot have a synodic period because a third solar system object is not involved. Although it would be a stretch to use an equinox or solstice, characteristics of the Earth itself, as the "third object", nevertheless, because they can be 'observed' relative to the Sun in a manner of speaking, the synodic period of the Earth would then be a tropical year, about 365.2422 days. The Moon is a third object, so its synodic period relative to the Sun is a lunation, new moon to new moon, about 29.53 days. — Joe Kress (talk) 21:12, 23 December 2008 (UTC)

Rotation

This section has a couple of sentences that I'm not sure are in keeping with WP:Summary style:

• The mean solar second between 1750 and 1892 was chosen in 1895 by Simon Newcomb as the independent unit of time in his Tables of the Sun. These tables were used to calculate the world's ephemerides between 1900 and 1983, so this second became known as the ephemeris second. The SI second was made equal to the ephemeris second in 1967.
• Recently (1999–2005) the average annual length of the mean solar day in excess of 86400 SI seconds has varied between 0.3 ms and 1 ms, which must be added to both the stellar and sidereal days given in mean solar time above to obtain their lengths in SI seconds.

Will anybody object if these are moved to the Earth's rotation article? Thanks.—RJH (talk) 16:59, 3 November 2008 (UTC)

I added those sentences to both this article and the Earth's rotation article at the same time, but I have no objection to their removal from this article. — Joe Kress (talk) 00:59, 8 November 2008 (UTC)

Thank you.—RJH (talk) 22:59, 8 November 2008 (UTC)

A useful addition would be to actually quantify the rate of slowing of the earth's rotational speed, but I'm not qualified to do that myself. The Wikipedia article on Tidal Acceleration quotes a figure of 2 ms / 100 years, but that seems far too small in the light of a TV news article today, that has informed us that since 1972, our clocks have had to be adjusted by 23 seconds, i.e. approx. 0.65 seconds per year. Have I misunderstood this news article? Can anyone supplement the 'Rotation' section with accurate information on this subject?Snookerrobot (talk) 19:07, 31 December 2008 (UTC)

The 'Moon' section of this article gives 23 µs a year, which references a NASA web site. I've seen CNN make some pretty bone-headed errors before, so I don't quite trust the TV news for science stories.—RJH (talk) 20:28, 31 December 2008 (UTC)

All are correct, but the explanation is a bit complicated so it may not be suitable for a summary article such as this. Earth's rate of rotation is slowing by 1.7 ms/d/cy on average over the past 2700 years based on observations of total solar eclipses (close to 2 ms/cy). Dividing by 100 years per century means that over one year the day lengthens by 17 μs. NASA's figure of 23 μs/yr is 2.3 ms/cy, which excludes –0.6 ms/cy of post glacial rebound since the last Ice Age which does not affect the Moon. Dividing 17 μs by the number of days in one Julian year, 365.25 days, means that each day has been longer than the previous day by 46.5 ns on a long term average. However, annual, decadal, and centurial variations around this average value exist. Because leap seconds usually don't occur more frequently than once a year, we can average out the annual variation. Thus since 1972, the decadal variation has dominated. Each day has averaged about 1.8 ms longer than a day of 86,400 SI seconds since 1972 according to data from the IERS (fluctuating between 3.13 ms and 0.27 ms). Multiplying by the number of days in 37 years (1972–2008), about 13,500, yields 24.3 seconds. There have indeed been 24 leap seconds since January 1, 1972. — Joe Kress (talk) 02:42, 2 January 2009 (UTC)

Bug in the article?

In the language box, the uppermost link (for me) is to a Norwegian bokmål template about the person of the year, which doesn't really have much to do with the Earth. I tried to see if I could remove it but I couldn't figure out how. Could anyone help me remove that link? Torswin (talk) 00:25, 2 January 2009 (UTC)

Fixed at Template:Time Persons of the Year 1976–2000 navbox. Or so I hope. --an odd name 00:42, 2 January 2009 (UTC)

It's fixed for me. Thanks :) Torswin (talk) 20:46, 2 January 2009 (UTC)

There is no valid proof that the Earth or this universe is as old as the article says

I still can't believe things like "the earth is such and such million or billion years old" are still being accepted as fact. I myself believe in the creation described in the Bible, but there is no proof to make either my belief, or these other beliefs SCIENTIFIC. Science has NO part in this, and can NOT prove how old our world is, OR how it was created. Who's to say that the laws of physics were EVEN THE SAME those millions or billions of years ago?! I'm quite frankly appalled that this is in the article. —Preceding unsigned comment added by 64.108.171.211 (talk) 21:12, 9 October 2008 (UTC)

See Wikipedia:Talk page guidelines.—RJH (talk) 22:18, 9 October 2008 (UTC)

Thank you for projecting the christian veiw of creation, now, may i point you into the direction that we use the scientific way as that is nuetral.--Jakezing (talk) 01

52, 7 November 2008 (UTC)

Science has no business conducting science? Right. I think you've come to the wrong Wiki, might I suggest: hereF33bs (talk) 06:50, 23 November 2008 (UTC)

An encyclopedia is not necessarily scientific, but verifiable - is that right? Spur (talk) 17:09, 9 December 2008 (UTC)

The claim about the age of the earth in this article has sufficient citations. They are entirely valid and scientific. That is all. --Sadistic monkey (talk) 10:55, 15 December 2008 (UTC)

The claim that the earth is 4.5bn years old does not, as is commonly thought, contradict the biblical account. The biblical Genesis account talks of a 7 day creation but it must be understood that the word 'day' in the book of Genesis is a translation from the old Hebrew of a word that could mean either a day of 24 hours / one rev of the earth, OR an 'era' or unspecified period of time, possibly of very long duration. Having said that, I think it would be more accurate (speaking as a scientist) to say that the Earth is thought to be 4.5bn years old, rather than saying that it is 4.5bn years old. The reason I say this is because there is a signicant, though admittedly small, body of scientific opinion that believes the earth to be much younger. There are various published scientific papers on this subject. As a comparison example, the scientific evidence for, and consensus of scientists belief in, the existence of the atom, is very much greater than the evidence for and consensus of belief in the age of the earth. Therefore in scientific terms it is reasonable to treat the atom as a certainty, but with the age of the earth, it would be fairer to say that there is a significant level of doubt. Hope this clarifies things a bit.80.41.138.18 (talk) 15:49, 2 January 2009 (UTC)

The talk page of the Age of the Earth article is the appropriate place to discuss this. Thanks.—RJH (talk) 16:42, 2 January 2009 (UTC)

Just because the facts on this page don't adhere to your myths does not mean they are false. If you have no proof that the myths you believe are true then why do you believe them? And there is plenty of evidence that the earth is billions of years old Look up the big bang theory,evolution,fossils,universe.82.23.62.255 (talk) 19:07, 29 January 2009 (UTC)

There are many people who strongly disagree of the age of the earth, regardless of scientific studies. Furthermore, science has not "PROVEN" anything, they only "BELIEVE" that the earth is 4.5 billion years old. In this article, this issue could be avoided by saying "It is believed by most scientists that the world is 4.5 billion years old" or something along those lines. But Wikipedia has no authority to "set it in stone" because it is contrary to many people's beliefs. 97.102.151.47 (talk) 14:02, 8 February 2009 (UTC)

It does not matter what people BELIEVE, wikipeadia is an encyclopedia for facts, if you wants beliefs then read the bible. Like i said if you want proof the earth is billions of years old visit those pages i mentioned above. they aren't beliefs those are proof.82.23.62.255 (talk) 22:11, 8 February 2009 (UTC)

And also check out wiki pages for "age of the earth" & "History of the Earth". learn something new. 82.23.62.255 (talk) 22:15, 8 February 2009 (UTC)

You also might want to check out http://conservapedia.com/Earth. If you think modern dating techniques are "just a theory" then Wikipedia might not be for you. Qc (talk) 14:12, 24 February 2009 (UTC)

Number of satellites

The infobox says "Satellites 1 (the Moon)" However, there are many, many, man-made satellites also orbiting the earth. I propose changing this to say "Natural Satellites 1 (the Moon)" —Preceding unsigned comment added by 173.87.22.75 (talk) 18:49, 1 March 2009 (UTC)

This is because the infobox for Earth is standard with all the other planet infoboxes where satellites wouldn't be ambiguous. But really, there's not much benefit adding natural satellites for this infobox, it's fairly obvious what it means. LonelyMarble (talk) 22:00, 1 March 2009 (UTC)

Time persons of the year?

That navbox does not belong in this article. Opinions? --Sir48 (talk) 11:37, 5 February 2009 (UTC)

Removed. StephenHudson (talk) 14:30, 9 February 2009 (UTC)

Why, really? The template links here. Personal computer still has it, too. —JAO • T • C 14:59, 9 February 2009 (UTC)

Sorry, I didn't look closely enough. It sounded like it shouldn't have been there, but apparently Earth was the “Person of the year″ once. StephenHudson (talk) 15:14, 9 February 2009 (UTC)

That looks like an error in the template. The Time Person of the Year article lists environmentalism as having obtained the award and not the Earth. Secondly, looking at the collection of navboxes (Earth-related topics - Earth's location in space - Elements of nature - Times persons of the year) shows a totally different perspective in the latter one, not having anything to do with the subject of the article. --Sir48 (talk) 16:10, 11 February 2009 (UTC)

I agree that the Time template seems out of place, but there didn't seem to be enough consensus to have it removed. (My earlier removal of that box was reverted.) Perhaps it belongs on the Earth in culture page instead?—RJH (talk) 18:04, 11 February 2009 (UTC)

Yes, the point that it's the Endangered Earth, rather than just Earth, that received this "award", definitely makes the template's inclusion here more problematic. Good points have been made here. I'll notify about the discussion over at Talk:Time Person of the Year. —JAO • T • C 18:42, 11 February 2009 (UTC)

Without any reactions I've been bold and changed the navbox to link to environmentalism and consequently have removed that navbox from this article. --Sir48 (talk) 17:01, 3 March 2009 (UTC)

Suggested modifications/additions

The following discussion is closed. Please do not modify it. Subsequent comments should be made in a new section. A summary of the conclusions reached follows.

The suggested improvements in this list, generally pertaining to geology, have been inserted into the article. Awickert (talk) 18:45, 15 March 2009 (UTC)

---

I've been reading through the article, and there are some things I would like to change. As it is a featured article, I'd like feedback before I touch it.

1. Y (Removed. Awickert (talk) 08:37, 8 March 2009 (UTC)) 3rd paragraph of lede: I'm going to have to check this, but there seems to be too much certainty implied in the water from comets hypothesis. As far as I know, this is one hypothesis, and there is no conclusion.
2. Y (Awickert (talk) 04:13, 12 March 2009 (UTC)) [tick removed: early tectonics Awickert (talk) 05:05, 11 March 2009 (UTC)] (Awickert (talk) 18:56, 8 March 2009 (UTC)) Chronology:
   1. Y Yes; did it. (Awickert (talk)) Should we also include the 4.567 Ga age of the earliest solar system material?
   2. Y (Awickert (talk) 07:15, 8 March 2009 (UTC)) All geological and geophysical evidence I know of points to the moon being knocked off of the Earth in a collision; I think "possibly" is too weak, as in the Earth and Planetary science community, contrary views to this hypothesis have become fringe.
   3. Y (Awickert (talk) 04:13, 12 March 2009 (UTC)) [tick removed Awickert (talk) 05:05, 11 March 2009 (UTC)] Re-wrote with references. (Awickert (talk)) The total size of the continents has likely not doubled over the past 2 billion years, and the continental area has not steadily increased. The amount of preserved continental material decreases with age because it can be destroyed. The general more modern geochronolgoical viewpoint (which works well with the idea of the continents as a steady-state conductive lid on the planet's heat loss system) is that the continents came to their present-day area relatively rapidly, and that area stayed the same ever since. This is still under debate, but the article seems to support the view based on the thought that crust isn't destroyed.
3. Y (Awickert (talk) 06:56, 8 March 2009 (UTC)) Shape: The geoid is not the shape, and in fact, doesn't correlate with topography, but instead with mantle structure. The geoid would be the shape of a completely fluid planet. I would change this to keep the reference spheroid, and to indicate that local topography can deviate from the spheroid.
4. Y Internal structure
   1. Y Added this, improved phrasing in internal structure and tectonics. (Awickert (talk) 22:31, 8 March 2009 (UTC)) Perhaps should make clear the crust (chemical boundary) and lithosphere (mechanical boundary)? This could help the structure/plate tectonics sections tie together and not be repeating similar things.
   2. Y Added w/ big table and shiny new section. (Awickert (talk) 05:05, 11 March 2009 (UTC)) 20-50% of the internal heat is from accretion, in addition to that from radioactive decay
   3. Y Tectonics & conduction. (Awickert (talk) 05:05, 11 March 2009 (UTC)) If we mention mantle plumes, should also mention tectonics, as heat-loss mechanism.
5. Y Moved & improved. (Awickert (talk) 22:42, 8 March 2009 (UTC)) Surface: 3rd paragraph should be in "tectonics", I think.

I think that's as much as I'll hit at one shot. So anyone want to comment / give me the go-ahead on one or more of the aforementioned issues?

Awickert (talk) 07:48, 7 March 2009 (UTC)

OK - it's been like a day, and since this is a FA, I'm guessing it's watched well enough that there aren't any major objections; I'll be going ahead, and checking off the items on the list above as I complete them with a Y. Of course, if there are feedback or objections, I'd like to hear it. Awickert (talk) 06:32, 8 March 2009 (UTC)

I do have an issue with this statement: "the current leaning of the geologic community is toward rapid initial growth of continental area". This conflicts with Wikipedia:MoS#Unnecessary_vagueness. The original statement had meaningful data; the current sentence could be interpreted widely. Please could you address this? Thanks.—RJH (talk) 22:49, 9 March 2009 (UTC)

De Smet, Van den Berg and Vlaar (2000) state that, "Within ca. 0.6 Ga after the start of the experiment, secular cooling of the mantle brings the average geotherm below the peridotite solidus thereby switching off further continental growth". Is this what you had in mind when you said rapid initial growth? Thanks.—RJH (talk) 20:34, 10 March 2009 (UTC)

Yeah, that's what I was going for. Let me re-word that, and tell me what you think. Awickert (talk) 23:11, 10 March 2009 (UTC)

OK - updated - but I'm afraid it's still sort of wishy-washy. The problem is that there are still geologists on both sides of the fence, so I don't feel OK only putting down the more widely-accepted theory, especially as the #1 problem is lack of evidence. What would you suggest? Awickert (talk) 23:24, 10 March 2009 (UTC)

It looks good now. Thank you.—RJH (talk) 19:02, 11 March 2009 (UTC)

Thanks so much for the style clean-up. I really appreciate it! Awickert (talk) 04:09, 12 March 2009 (UTC)

Y All Done! I'll wait a few days for more comments and then archive this as it's mostly just a finished checklist. Awickert (talk) 04:13, 12 March 2009 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

Chemical composition

I tried to hunt down the primary source for the data in the second paragraph of the "Chemical composition" section, as well as "F. W. Clarke's Table of Crust Oxides". I think I have it narrowed down to perhaps the first edition, Chapter I of:

Clarke, Frank Wigglesworth (1911). Bulletin 491: The Data of Geochemistry (2nd ed.). United States Geological Society. Retrieved 2009-03-06.

The data in this article's table does not quite match the values on page 32 of the above, so my initial inclination was to use the values from the book (which was published the same year as the encyclopedia listed as the reference). However, I understand there were subsequent editions of this book, so those values may differ as well. What do you think? Perhaps there is a final edition sitting in a university library somewhere? :) —RJH (talk) 20:01, 5 March 2009 (UTC)

I actually do not understand why this paragraph refers specifically to Clark. There is a large number of modern sources about the crustal composition. Ruslik (talk) 20:17, 5 March 2009 (UTC)

I'd think that there should be some more updated composition, since it is almost 100 years later with all those great scientific advances. I checked a book I had laying around (Geodynamics) and it doesn't have it, but I'll keep looking and update when I find something, unless someone beats me to it. Awickert (talk) 08:00, 7 March 2009 (UTC)

I agree with both of you. An update would be much appreciated.—RJH (talk) 21:51, 9 March 2009 (UTC)

Found some model estimates; still looking. Awickert (talk) 23:34, 9 March 2009 (UTC)

Did you have any success?—RJH (talk) 20:56, 17 March 2009 (UTC)

Hydrosphere

The article states that the hydrosphere

"...technically includes all water surfaces in the world, including inland seas, lakes, rivers, and underground waters down to a depth of 2,000 m."

Is it possible to find a source for the limitation to 2,000 m? --Sir48 (talk) 17:47, 15 March 2009 (UTC)

It's from Shiklomanov et al. (1999). I need to fix the link.—RJH (talk) 20:54, 17 March 2009 (UTC)

Commas/Decimals

The quiantities in the Earth's statistics sometimes have a period instead of a coma when referring to thousands (ex. 6.371.0 = mean radius of the Earth) —Preceding unsigned comment added by 71.36.70.130 (talk) 21:13, 24 March 2009 (UTC)

I'm not seeing this problem, so it may be a clipping issue with your browser. If you increase your browser font size do you still see the periods?—RJH (talk) 22:24, 24 March 2009 (UTC)

In the box on the right side of the page, there appear to be inconsistencies in format for some of the numbers. Should the Mean Radius and Polar Radius be written 6.371.0 km 6.356.8 km? 129.49.84.108 (talk) 18:56, 26 March 2009 (UTC)

I see "6,371.0 km" and "6,356.8" km as one might expect in English, the comma being a thousands separator and the period being a decimal separator. —JAO • T • C 19:09, 26 March 2009 (UTC)

All right, I've seen it now. These lines clip in IE7, with all font sizes except the largest. Not in Opera, Firefox or Chrome though. I have no idea why it's so. —JAO • T • C 21:37, 26 March 2009 (UTC)

That's curious. It looks okay to me on an IE browser. Maybe it's your browser version or your PC's fonts?—RJH (talk) 18:52, 27 March 2009 (UTC)

On IE7 I see this same problem. On other browsers like Jao mentioned, including Safari, there isn't this problem. One reason might be other browsers have slightly smaller default text/font sizes than IE. If you actually zoom out once to make the text smaller in IE the problem is solved. Also if you zoom in two or three times the problem is also solved. So it seems the only problem is default text/font size on IE7 the bottom of the comma is cut off in these two parameters. Must just be a small interference with the adjacent parameters that cuts off some of the text, you see this in other places on Wikipedia, like sometimes navigation boxes that are right-aligned can interfere with text. There may be a way to fix this problem but it's such a small one it probably doesn't matter. LonelyMarble (talk) 21:24, 27 March 2009 (UTC)

Wikipedia:Articles for deletion/Earth (2nd nomination)

Happy Apr 1st. --Ron Ritzman (talk) 02:33, 1 April 2009 (UTC)

And yet it might actually make sense. The International Astronomy Union is planning to discuss celestial body naming conventions later this year. One proposal is to rename Earth after the Roman goddess Cybele so it falls in line with the standard planetary naming scheme.—RJH (talk) 18:55, 1 April 2009 (UTC) ;-)

That actually sounds like a really good idea.  Marlith (Talk)  22:55, 1 April 2009 (UTC)

LOL! You got me.Makewater (talk) 20:06, 6 April 2009 (UTC)

Why all the "Earth is the only known..." speech?

Isn't one sentence in the intro saying Earth is the only known planet with life and liquid water currently on its surface enough? It seems most facts are followed by how unique the Earth is; we only know of about 200 extrasolar planets, and we have only very rough estimate of the atmosphere of 1 or 2 of those 200. This is an article about earth, not the article on the probability of life in the universe. Lets make those statements a little more concise. 98.202.48.28 (talk) 23:43, 30 September 2008 (UTC)

I'm not sure what you're suggesting; could you clarify? There is only one sentence on that topic. If you're referring to the second paragraph of the intro section, I think the rest of the paragraph is good summary material. —Alex (ASHill | talk | contribs) 03:02, 1 October 2008 (UTC)

He is just saying, and I agree with him, that this part: "Earth is the only place in the universe where life is known to exist" has no place in this article. It is an assumption that serves no purpose. It should be removed.

No, the Earth is the only place that we know of that harbors life. The sentence refers to human knowledge. There probably is life elsewhere. Saros136 (talk) 08:41, 12 February 2009 (UTC)

There we go again. But it's not a statement about Earth (subject of this article), but about the rest of the universe. It does not belong here. −Woodstone (talk) 08:49, 12 February 2009 (UTC)

This encyclopedia is written for humans and represents a human understanding of the universe. That life is only known to exist here is a unique and very notable aspect of this planet. Therefore it most definitely does belong here.—RJH (talk) 15:40, 12 February 2009 (UTC)

A very notable aspect of this planet that is in most likelihood false. But that's just the point, that Earth is the only place in the entire universe to harbor life is conjecture. It's a guess. How can the article state something like that when we have barely started looking at planets beyond our own solar system? For an article otherwise based on fairly solid scientific facts this sentence seems very out of place.

The article does not say this is the only place in the universe to harbor life. It is the only where life is known to exist. Referring to human knowledge. The Encyclopedia Britannica says about the Earth Its single most outstanding feature is that its near-surface environments are the only places in the universe known to harbour life. http://www.britannica.com/EBchecked/topic/175962/Earth Saros136 (talk) 02:18, 16 February 2009 (UTC)

The wording Britannica uses is even more perplexing. If I find a stone in my backyard, a backyard I've never left, is it outstanding because I know of no other stone like it, in all the world? Not at all. If I examine the whole world, and find no other stone like it, then it is outstanding. You can't glorify something based on a lack of knowledge. Obviously Earth is the only known planet to harbor life, relatively speaking it may as well be the only stone we've found. We've barely (and that's a generous word considering the size of the universe) started looking, so saying it's the only such place in the universe, that we know of, is completely redundant.24.79.197.49 (talk) 03:37, 16 February 2009 (UTC)

That's a straw man argument. If the stone in the backyard happens to be a sapphire, it's definitely an unusual one. Whereas we phrase it that it is the only "known" planet to harbour life, we are making a correct and relevant statement. Though it's certainly true that there could be life elsewhere, that fact doesn't degrade the fact that it's the only one known to humans to have life. {{Nihiltres|talk|log}} 05:33, 16 February 2009 (UTC)

Since there are probably millions of planets supporting life, it is unclear if this "feature" of this one planet makes it notable in and of itself. There are trillions of planets without articles, so what is so special about this one? It seems unlikely that this planet satisfies W:Notability. Therefore I recommend deleting this article and any other articles focusing on particulars of this one planet, including its history, biology, and geography. For some examples, by following Special:Random I found the following articles which are only notable if we assume the importance of nearly all trivia about this one world: Rzeszów County, Acoetes, Koolhoven F.K.30, Four Buddhist Persecutions in China, Taycheedah, Wisconsin, Tenages, WJPG, Bhatgaon, Raipur, Boyd Big Tree Preserve Conservation Area, Alexander Romanovsky, et cetera. Indeed, it took 14 random pages before I found one which has any claim to be of more universal application, Current (mathematics), although even that article takes an Earth-centric perspective since it is presented in a way which is ultimately derived from fundamentally human understandings gleaned from one particular vacuum-state pocket of the universe. Due to the high percentage of Wikipedia contributors who are humans and inhabit this particular planet, it will probably take a concerted effort involving W:WikiProject Countering systemic bias to help us meet our W:NPOV guidelines. I've noticed that many users have in the past attempted to reduce this article to one or two relevant keywords, which would probably be a good start to cleaning up this mess. Any thoughts? ;) -- Kevin Saff (talk) 02:24, 14 March 2009 (UTC)

I would have to agree with you Saff, but where do you think you will get with this? Remember Ignore all rules, and in the making of a direct democracy, this will be a rule that is ignored. --< Nicht Nein! (talk) 17:46, 14 March 2009 (UTC)

Kevin Saff: The key word in the sentence is "known". Your arguments are based on guesswork and not certainty. Beginning an argument with pure speculation and then using it to buttress and justify the remaining statements does not provide a shred of factual evidence. If you can substantiate the first sentence with credible citations from the scientific community, minus the word "probably", then we can modify the article accordingly. Until that time, I see absolutely no reason to change the assertion that this is the only place known (by humans) to contain life.—RJH (talk) 21:20, 14 March 2009 (UTC)

Also want to point out that the star article says there are at least 70 sextillion stars in the observable universe, so even if trillions of planets contained life, this would certainly still make them all notable, given the vast amounts that don't contain life. And given the speed of light, it's going to take humans a long time, if ever, to get in contact with other life forms, so I would imagine our storage capabilities for trillions of Wikipedia articles would be pretty advanced at that point in the future, so I wouldn't worry about it. This is only a compendium of all human knowledge, which pretty much saps any further argument right there. If other life forms give us more knowledge then it enters into human knowledge. I suppose if advanced life forms meet and exchange knowledge it would simply be all known knowledge within an intergalactic community. LonelyMarble (talk) 21:35, 14 March 2009 (UTC)

Hi. Sorry I don't know how this is done, but I just wanted to mention that the sentence in question is factually and grammatically incorrect. "Earth is the only place in the universe where life is known to exist". It presumes upon facts not in evidence. Neither can the facts be known at this time, nor does all of humanity agree with the assertion as it stands. To know what's known, we'd have to know what in the universe knows things. We don't. Earth is believed by some to be the only place in the universe where life exists. That's as close as you can come. Many cultures assert that there's life on other worlds, in other dimensions, and in different states of being. Many cultures define life in different ways, nor is the definition completely clear in a scientific context. The scientific fact of life not being found on other planets is unremarkable enough to void need of mention, given the tiny cross section of planets we've examined closely enough to detect life. In short, neither do we get to state empirically what is known, nor do we get to make a similar claim for what all of humanity supposedly knows - especially since it simply isn't what everyone thinks they know. [just some guy who read the article] —Preceding unsigned comment added by 24.7.71.229 (talk) 03:07, 25 March 2009 (UTC)

Oh my god. I can't believe how long this discussion is. The keyword is KNOWN, people. Earth is the only place we KNOW to have life. That's true. End of story! --81.97.47.128 (talk) 16:04, 20 April 2009 (UTC)

Image of the Tectonic plates section

I think it looks odd to have the .svg image after the text. It looks like it has fallen down or something. How would it be if the image was right-adjusted, hugging the right wall of the browswer and having the text to its left? /Tense (talk) 13:40, 23 March 2009 (UTC)

The change made to address this issue was not an improvement. In fact it seems worse now.—RJH (talk) 18:57, 23 March 2009 (UTC)

I think the edit done by Woodstone makes it better, but it still needs improvial. My suggestion for its general placement: Increase the size of the whole image box, "Earth's main plates", making its height just as high as the height of the three paragraphs to the left of it.

Other issues I think should be dealt with:

• The image is so small it's impossible to distinguish any letters in the image. In the table you can read about the main plates and their size. I think it would be a lot more informing if the names for those plates were scaled and subsequently made readable in the article - so that you don't have click the image. I guess most people can find the African plate but I still believe that it would be more informative.
• The text "A map illustrating the Earth's major plates." is misplaced in my opinion. I should be just below the image. But placing it there creates another problem: it would be a huge empty space below it. If one were to lower the font-size in the table OR increase the size of the image that empty space would be removed. /Tense (talk) 21:11, 23 March 2009 (UTC)

I'm not seeing this improvement you speak of. All that seems to have been done is that the image/table was moved to the top of the section, producing an ugly break before the start of the text. The image itself may need to be modified to make it useful; perhaps a reduced version with larger text would work? The plate names could be put in nowrap templates, eliminating the line breaks. I'm not sure how to get the image caption to snuggle up against the image without using a thumb version.—RJH (talk) 22:35, 23 March 2009 (UTC)

I know too little of how Wiki-articles should look in order to give you/the article further feedback. I'm sorry. /Tense (talk) 10:44, 31 March 2009 (UTC)

Because the image scale on the tectonics world map makes the labels unreadable, my suggestion is to try using the unlabeled map at File:Tectonic plates (empty).svg, then provide a link to a labelled map. Would anybody object to this?—RJH (talk) 17:39, 29 March 2009 (UTC)

A good idea, in my opinon. It would make it more clear. /Tense (talk) 10:44, 31 March 2009 (UTC)

Nobody objected, so I went ahead and inserted the unlabelled image with a more vertical arrangement. We'll see if anybody complains... —RJH (talk) 19:02, 31 March 2009 (UTC)

I cannot find the link to the labelled map that you spoke of. Shouldn't the image itself link to it? /Tense (talk) 16:36, 8 April 2009 (UTC)

I wikilinked the table caption, even though this is redundant with the wikilink in the text. Will that serve?—RJH (talk) 22:10, 8 April 2009 (UTC)

Leaving Earth

Recent edits have removed Yuri Gagarin as the first person to leave Earth. I believe it should be in because although he did not altogether leave the atmosphere, he went into what is popularly known as "outer space", and what he did would generally be considered as the first person to leave Earth. Based arguments on leaving the atmoshere, if we use the exponential decay model for the atmosphere, we never fully leave it; we must just define some limit. So I propose that either we leave this in, or re-define "atmosphere" and say that he went far out in the atmosphere, and then the Apollo astronauts left Earth altogether (Apollo astronauts leaving Earth seems unarguable to me.) Awickert (talk) 09:18, 21 March 2009 (UTC)

First - Gagarin have not left Earth's atmosphere. Not Earth's ionosphere or exosphere. The guy got into outer space, into so called Low Earth Orbit. Any object from there would be dragged down by Earth atmosphere. Just like an air plane would be downed by it. Sure in first case it will take longer time, since atmosphere not very dense on LEO. But in each case term "left an Earth" could be easily applied to air plane of Wright brothers or Gagarin himself. Vitall (talk) 09:32, 21 March 2009 (UTC)

I replaced with "humans who travelled the farthest from the planet". You said "what he did would generally be considered as the first person to leave Earth." Here what generally considered is factually incorrect unless we can come up with strong and universal definition of "leaving the Earth". That include reasons why leaving just an Earth surface(air planes, balloons) not good enough. Leaving an Earth atmosphere is a good starting point, but, yes, in this case we need to know exact boundaries of it. Vitall (talk) 10:18, 21 March 2009 (UTC)

Well, I wouldn't say he felt much in the way of drag up there, but I see what you say about the leaving the atmosphere thing. Gagarin is still significant, so perhaps it should be somewhere (first outer atmosphere?). Looking at the atmosphere definitions, it seems that the Apollo missions would have definitely left the atmosphere. I like your addition of the farthest we've been. So maybe somewhere in the article, humans leaving Earth: Wright (flight), Gagarin (low orbit), Apollo 11 (outside the atmosphere and to another planetary body), and Apollo 13 (furthest).

Unfortunately, your new and more specific addition doesn't flow with the paragraph as well, any ideas on how to deal with that? Awickert (talk) 10:31, 21 March 2009 (UTC)

The article is about Earth, not the Earth atmosphere or amount of drug on low earth orbit. Again any object in Earth's atmosphere will be eventually brought down, doesn't matter object flying in thermosphere or troposphere. Main question is why would you think "leaving Earth" could be applied to object flying in ionosphere but not in troposphere. Gagarin is sure significant. Add him to space exploration, outer space etc. and so on.

I'll try to rephrase it. Vitall (talk) 10:51, 21 March 2009 (UTC)

OK - or we could leave it out entirely - I was listing milestones to try to help, and do indeed say that Gagarin was outer atmosphere. The drag thing was just my deal: I do fluid physics a lot, and there would be really really low drag there. Awickert (talk) 10:56, 21 March 2009 (UTC)

I reverted these edits as the issue is in dispute, and, well, I also disagree with the change. Why is this even an issue? It is a widely accepted fact that Yuri Gagarin was the first human to reach outer space and to enter Earth orbit. The definition of outer space is also generally accepted as the Kármán line: 100 km above the surface.—RJH (talk) 01:48, 22 March 2009 (UTC)

Before asking "What is an issue?" - please read this very section. It fully explain it. Issue has nothing to do with outer space and it definition. Question right in the caption - what should be considered "leaving an Earth"? If someone have gone into thermosphere - why it would make him "leaving an Earth" when someone who flown airplane to troposphere are not. Both left surface. Both still inside atmosphere and eventually be brought down by an atmospheric drag. I will revert, and please do not restore sentence in question until dispute resolved. Vitall (talk) 03:22, 22 March 2009 (UTC)

As both the deleted sentence and the new addition were not covered by the body, I moved them down to the Human Geography section per wikipedia policy WP:LEAD. Please edit them at that location. If you come up with a suitably condensed summary sentence, then we can update the lead.—RJH (talk) 18:52, 23 March 2009 (UTC)

How about this wording: In 1961, Yuri Gagarin became the first human to reach outer space and orbit Earth; he was 327 km above Earth's surface at his highest point.[7] Humans traveled the farthest from the planet in 1970, when the Apollo 13 crew was 400,171 km away from Earth.[8][9] LonelyMarble (talk) 18:54, 22 March 2009 (UTC)

Also a comment to Vitall: in the first reference you gave for the farthest away fact, one of the other facts is: "The Russian cosmonaut Yuri Gagarin was the first human in space in 1961". This is a common fact, I took out the "leave Earth" wording though as I guess that is slightly ambiguous and not exactly the same as "reach space". LonelyMarble (talk) 19:08, 22 March 2009 (UTC)

It is fine now. Gagarin reached the outer space, not left an Earth atmosphere. That was whole point, but, as i have said, article is fine now. Vitall (talk) 07:41, 1 May 2009 (UTC)

Given the growth in sub-orbital space tourism, I think that reaching Earth orbit is a much better discriminator than merely reaching outer space.

According to Outer space, 50 miles up is sufficient to be an astronaut. Wikipedia also finds common usage to be satisfactory in many cases. In this context "leave" is generally understood to not include the meanings which include "death", but rather reasonable similarity to Earth's surface. And if the endless attenuation of the atmosphere is to be considered as the limit of the planet, the Moon's atmosphere could be considered as part of Earth's when sufficiently "downwind". -- SEWilco (talk) 19:46, 22 March 2009 (UTC)

This is irrelevant. Vitall (talk) 07:42, 1 May 2009 (UTC)

Not entirely. I don't think the 50 miles up value is correct.—RJH (talk)

Deadlinks

I've just checked the links, it turned up four error 404:s: Layers of the Earth(Cite:88), Terrestrial Impact Cratering and Its Environmental Effects(Cite:87), Canadian Forces Station (CFS) Alert(Cite:154) and Mineral Genesis: How do minerals form?(Cite:146). Gsmgm (talk) 14:35, 8 April 2009 (UTC)

I've replaced the links with valid addresses. Thank you for going to the trouble of checking the reference links.—RJH (talk) 16:32, 8 April 2009 (UTC)

No problem, happy editing. Gsmgm (talk) 11:51, 3 May 2009 (UTC)

Creation

Creation (and challenges to darwinist claims) should be included. This article wrongly presupposes evolutionary theory. —Preceding unsigned comment added by 68.5.190.41 (talk) 10:21, 23 March 2009 (UTC)

This has been discussed before. The topic of creation myths is covered in the "Cultural viewpoint" section, and in other articles on wikipedia.—18:46, 23 March 2009 (UTC)

Do people really think that evolution is somehow connected the the formation of the earth? Evolution is about species reproducing, it has nothing to do with how the Earth was formed. —Preceding unsigned comment added by 74.83.75.110 (talk) 16:28, 25 May 2009 (UTC)

Your discussion topic falls under the perview of WP:PSCI. You've also mistaken this article for History of the Earth. Creationism is covered on its own article, and the more general subject of religious views is briefly discussed under the Cultural viewpoint section.—RJH (talk) 17:40, 25 May 2009 (UTC)

Orbit Section adding image of Milky Way location

I wanted to add this image

Illustration of the Milky Way Galaxy showing the location of the Earth's Sun.

to the "Orbit" section, to illustrate and show the vast context of Earth and our Solar system. Since I've only just created a Wikipedia account can someone add this for me? Having an image along with this statement in the Orbit section...

"Earth, along with the Solar System, is situated in the Milky Way galaxy, orbiting about 28,000 light years from the center of the galaxy, and about 20 light years above the galaxy's equatorial plane in the Orion spiral arm."

... will really help people understand and see just where we are in our area of our galaxy. —Preceding unsigned comment added by Neotint (talk • contribs) 21:56, 10 May 2009 (UTC)

Sounds like a good idea to me, I'm putting it in with a couple of tweaks. Awickert (talk) 01:23, 11 May 2009 (UTC)

Even at the scale of the image above, the location of the Sun is not apparent.—RJH (talk) 22:15, 14 May 2009 (UTC)

I can see the lines that converge on the sun, though - maybe we should annotate it with a red circle? Awickert (talk) 23:28, 14 May 2009 (UTC)

I think that would make sense. Also we would not need to use the large image size for an annotated version, although I don't know whether that would improve the download rate.—RJH (talk) 16:21, 15 May 2009 (UTC)

I'll do it within the next 3-4 days (pretty busy), unless someone wants it done more and beats me to it. Awickert (talk) 16:31, 15 May 2009 (UTC)

Earth Infobox

Hey, could someone convert the information about earth's surface area, etc. into Imperial units and put it in the Infobox? I know many people use the metric system, but for those of us living in the countries who haven't started using the metric system, it's a real pain to have to manually convert each thing as we need it.

Thanks much! —Preceding unsigned comment added by 71.35.181.248 (talk) 20:59, 24 May 2009 (UTC)

I agree, I'm gonna look to see if I can find a better place for this request. CTJF83Talk 08:28, 25 May 2009 (UTC)

Following some discussion, there was a consensus to only use metric in the infoboxes for the planets, per the guidelines for science pages. --Ckatz^chat_spy 18:46, 25 May 2009 (UTC)

Do you know where this discussion is, or how I can start a new one to get imperial in the infobox too? CTJF83Talk 02:54, 26 May 2009 (UTC)

See: Template talk:Infobox_Planet#American Units. Personally I wonder if it would be possible to design an tabbed infobox so that the reader can switch between Metric and American English units? – RJH (talk) 17:27, 8 June 2009 (UTC)

I presume then you would add British English ("Imperial") units too? Can't we just stick with the worldwide standard metric/SI units and let people use, eg, Wolfram Alpha if they want to convert the area to furlongs-squared or whatever. Pbhj (talk) 13:31, 20 June 2009 (UTC)

Pronunciation

I removed the pronunciation from the first sentence of the lead, but someone reverted me. It is not appropriate for an encyclopedia article to begin with the pronunciation, unless perhaps the word is uncommon and the pronunciation unobvious. "Earth" is a common word, and the pronunciation of common words is typical material for a dictionary, not an encyclopedia. Wikipedia is not a dictionary. Yes, one often sees pronunciation given in the lead of other Wikipedia articles. The fact that a mistake has been made in other articles is not good justification for continuing to make that mistake. --Srleffler (talk) 00:47, 12 June 2009 (UTC)

Linking to the "Wikipedia is not a dictionary" policy is not really appropriate; I read that page and saw nothing about having the pronunciation of articles in the lead. There seems to be no consensus involving this issue, so basically you are just giving your opinions here about what is appropriate. Another reason I reverted the removal is because all 8 of the planet articles have the pronunciation and they are all featured articles that are a part of a featured topic. Consistency in this case seems warranted. Finally, you have no idea who is reading the English Wikipedia. People who's native tongue is not English are reading it and words that seem common and easy to pronounce may not be for everyone. There doesn't seem to be any reason to remove the pronunciations to me, they barely cause any clutter and they could be potentially helpful. It's useful information to know how to pronounce the title of an encyclopedia article, because for people who read aloud in their head (as opposed to scanning-type reading), or are reading aloud to someone else, the pronunciation is key information. LonelyMarble (talk) 20:25, 12 June 2009 (UTC)

I agree that the pronunciation in the lead is useful. As for the policy that Wikipedia is not a dictionary, I don't think it's relevant here. It states that Wikipedia articles are encyclopedia articles and not dictionary articles, but this does not prevent an encyclopedia article from containing etymological, phonetic, or other such information (as long as it remains an encyclopedia article.) Spacepotato (talk) 00:46, 13 June 2009 (UTC)

The policy doesn't explicitly say "no pronunciation in the lead", but look at the comparison the policy makes between encyclopedia and dictionary articles. A dictionary article is about the word itself, while an encyclopedia article is about the concept the word describes. Concepts do not have a pronunciation. Putting the pronunciation in the lead sentence implies that the subject of the article is the word, rather than the underlying concept.

Besides the question of whether the article should contain this information, I object to the placement and format. Take a look at it: before we even define what Earth is, we give the word "pronounced", an icon of a speaker (that links to a media file), a sequence of strange characters that few people know how to interpret, and links to Wikipedia:Media help and File:En-us-earth.ogg. Is this really the most critical information we can provide about Earth? The lead is the most critical part of the article, and the first sentence is the most critical part of the lead. The pronunciation breaks up the flow of this critical sentence, and makes it harder to read. Providing pronunciation in parentheses after the word is appropriate style for a dictionary; it is not appropriate for an encyclopedia. If pronunciation needs to be given, it should be given in a full sentence further down in the article.

Very few, if any, readers of this article are going to need to be told how to pronounce "Earth", and those who do should probably be looking in a dictionary or reading the article on Simple Wikipedia. Putting the pronunciation in this position of prominence is putting information that is unlikely to be useful ahead of the critical content. Arguing that the articles on the other planets have it is not sufficient. The other planets' names are not as common as "earth" is, and I don't actually think pronunciation is appropriate in those articles either (although I'm willing to make an exception for Uranus).--Srleffler (talk) 01:37, 13 June 2009 (UTC)

It's appropriate to have at the beginning for the reasons I already mentioned, some people may not know how to pronounce the word and should be informed of the correct way at the first possible instance. I don't think it breaks up the flow that much, it's really not a big deal flow-wise. A lot of people will use Wikipedia as the first source of information about a subject. While I agree that dictionary creep in Wikipedia should be avoided, I don't think the pronunciation is dictionary creep. Just because a person should look to Wiktionary or another dictionary for pronunciation doesn't mean they will, and probably don't. LonelyMarble (talk) 14:24, 13 June 2009 (UTC)

I have a strong opinion that the pronunciation entry belongs in the Infobox, rather than the first sentence of the lead. My reasons are:

1. To me it significantly disrupts the flow of the lead, a key part of any article.
2. On a smaller browser the pronunciation frequently collides with the infobox, causing layout issues.
3. It belongs in a dictionary, and WP:NOTDIC.
4. The format of the pronunciation string violates WP:JARGON.
5. It frequently only provides American pronunciation; adding more would further disrupt the flow.

If the argument for retaining the pronunciation in the lead is that readers should not not have to jump to the wictionary, why then should they have to drill down to the pronunciation guide to undertand the information? Take, for example, the first sentence of the Mercury (planet) article. To me the entries between the slashes are complete gobbledegoop. It also includes a speaker icon and a help*info link. How is this useful when I'm trying to understand the planet mercury?—RJH (talk) 16:56, 13 June 2009 (UTC)

Having the pronunciation in the infobox is fine by me. You should probably bring that up at Template talk:Infobox Planet. The reason Wikipedia uses IPA for pronunciations is a similar reason as why the infoboxes for planets only use metric figures. IPA is supposedly the best method of pronunciation for people of any language to understand, and the pronunciations are supposed to the most accepted for English regardless of dialect. If you think a pronunciation is more American then you should bring that up individually. If the pronunciations are added to the infobox you could probably add in another way to present the pronunciation along with the IPA one, but that might be causing too much dictionary creep. LonelyMarble (talk) 17:36, 13 June 2009 (UTC)

Thanks. I think it would probably be good if we could have a standardized pronunciation sub-table template that we could slot into any infobox row. That way it all gets updated in one place.—RJH (talk) 15:38, 14 June 2009 (UTC)

LonelyMarble: "Earth" is such a common word, that I find it hard to imagine that anyone who doesn't know how to pronounce it will get any value from reading the article. Anyone capable of reading English at the level used in this article, will already know how to pronounce "Earth". Even if there is some very, very small number of readers who need to know the correct pronunciation, why must we cater to this tiny group's needs "at the first possible instance", at the expense of every other reader of the article. The pronunciation could be provided lower in the article, or in the infobox.--Srleffler (talk) 22:00, 13 June 2009 (UTC)

I agree with you that the infobox is a good place. One reason I am opposed to the removal in this article is because I am someone that likes consistency, so I think either all or none of the planet articles, that are part of a featured topic, should have the pronunciation. Considering the other planet names are not as common as Earth, I think keeping the pronunciation is probably better. If this article wasn't part of a featured topic I wouldn't care so much, but I like consistency. I agree with you that common article names don't really need pronunciation, but in this specific case it doesn't really cause much clutter in my opinion, but moving it to the infobox seems like a good idea and would make everyone happy. LonelyMarble (talk) 22:40, 13 June 2009 (UTC)

It would fit fine in the first section of the infobox titled "designations" (though that title may need to be altered). Listing the adjectives is really dictionary information too isn't it? So listing the pronunciation there would fit nicely. LonelyMarble (talk) 23:22, 13 June 2009 (UTC)

DONE.--Srleffler (talk) 22:32, 24 June 2009 (UTC)

It's a distinct improvement. Thank you.—RJH (talk) 17:22, 25 June 2009 (UTC)

This issue exists on other astronomical object pages besides the planets, so I started a discussion at Wikipedia talk:WikiProject Astronomical objects#Pronunciation, hoping for a more general consensus. Thank you.—RJH (talk) 18:55, 15 June 2009 (UTC)

Capitalization

The earth, sun, and moon should not be capitalized unless they are mentioned in relation to other heavenly bodies. Why are they capitalized in the article?Lestrade (talk) 14:23, 7 June 2009 (UTC)Lestrade

This was discussed in Archive 10 here: Talk:Earth/Archive 10#Capitalization issue. Basically, this article is most about Earth as a planet so the context of Earth in this article could be said to be in relation to other bodies in space. It's also treating Earth as a proper noun of a unique place in space, which the IAU recommends. I think it's best just to be consistent within the article and have all the astronomical objects capitalized. LonelyMarble (talk) 15:10, 7 June 2009 (UTC)

No, no, no. It's BEST to have the correct spelling (all lower-case letters) and not capitalize the term "earth" as the IAU's "recommendation" is at best flawed in calling earth a proper noun, and at worst full of itself for thinking that our spot in the universe is any more "unique" than anywhere else. Therefore, the IAU's definition is flat on it's face. earth is not a proper place or noun, and should not be treated as such by having every single "e" in earth capitalized incorrectly and improperly in this article. I DEMAND change immediately!98.209.67.70 (talk) 12:06, 4 July 2009 (UTC)

Welcome to Wikipedia. You aren't going to get very far demanding things here. This has already been decided through editorial consensus. Auntie E (talk) 13:41, 4 July 2009 (UTC)

His argument also makes no sense. Just because there are billions++ planets in the universe does not mean each planet isn't a "unique" place. Of course it is. There are billions of humans, thousands of cities and rivers, etc. All these things are proper nouns. Plus, is the IP suggesting the other planets in the Solar System should also be lowercase, as that would definitely be against "correct" "spelling". LonelyMarble (talk) 13:46, 4 July 2009 (UTC)

Adjectives

infoboxes tend to acquire a life of their own. This is a bad thing and needs to be counteracted. An infobox shouldn't contain any information that isn't explained and referenced in greater detail in the article. In this case, the alleged adjectives pertaining to Earth, not repeated anywhere in the article body,

Terrestrial, Terran, Telluric, Tellurian, Earthly

This is unvoluntary comedy. Of course these are all adjectives, and they all relate to Earth in one way or another, but they are very far from interchangeable. --dab (𒁳) 07:53, 30 June 2009 (UTC)

I have to disagree with your third sentence. There are some types of information that shouldn't need to be repeated in the article. For example: geographical coordinates, catalogue names, &c. I do agree that there is a lot of dictionary creep in the infoboxes, but at this point I'm just happy to get that moved out of the lead. No offense intended to the grammarians, of course.—RJH (talk) 18:27, 30 June 2009 (UTC)

There's no claim that these adjectives are interchangeable, it's just a list. If you click on the word "Adjective" that is linked, you will go to this article: Adjectivals and demonyms for astronomical bodies, which would be the place for more detailed discussion of these terms. LonelyMarble (talk) 13:54, 4 July 2009 (UTC)

Known Life

the earth is clearly flat and not round

It says that Earth is the only planet where life is known to exist. It should say that Earth is the only planet where earthling humans know life to exist. —Preceding unsigned comment added by 75.105.128.54 (talk) 23:52, 14 July 2009 (UTC)

This has been discussed before. Alien entities are welcome to edit the page accordingly, and present suitable citations refuting the current wording.—RJH (talk) 00:31, 19 July 2009 (UTC)

Earth Life Extension

http://www.sciencedaily.com/releases/2009/06/090612203303.htm

This source states that life could be around for much longer than previously anticipated. I think that this should be put into a section. —Preceding unsigned comment added by Trilobite12 (talk • contribs) 04:54, 19 July 2009 (UTC)

I added it to the section on future history. Thanks. Really though I think the entire topic of Earth's expected future deserves its own article so that the details can be expanded.—RJH (talk) 15:11, 19 July 2009 (UTC)

Neutrality

I think this article is obviously biased. Why, in the beginning of this article, does it say that the Earth formed billions of years ago? First of all, that is only one of thousands of theories. That makes this article biased. It puts the rest of the theories at the end, as if they're not as true, or important, or are merely other theories aside from the "billions of years ago" theory. At the beginning of this article, it should say that the creation of Earth is disputed, or arguable, or something. Not just that it "formed billions of years ago," which is just another theory like all the others. --75.185.109.23 (talk) 20:00, 13 April 2009 (UTC)

Pray tell, what are these other "thousands of theories?" —Preceding unsigned comment added by 24.95.247.110 (talk) 09:20, 9 May 2009 (UTC)

Furthermore, you seem to be under the impression that "theory" means "guess." The word you're mistaking it for is "hypothesis," and you would be wrong if you were to use it to describe Evolution in the first place. —Preceding unsigned comment added by 24.95.247.110 (talk) 18:49, 7 June 2009 (UTC)

Been discussed ad nauseum. Please see the archive and Age of the Earth. -- Amory (talk) 21:27, 13 April 2009 (UTC)

For future reference, is it appropriate to categorize these types of arguments under the WP:PSCI policy, and label them as "obvious pseudoscience"?—RJH (talk) 20:13, 14 April 2009 (UTC)

Why mention only humans on the opening chapter, any species, f.e Tympanobasis, could do? And the notion that humans live on earth isn't referenced, so it is also doubtful.

Species Tympanobasis is free to edit the article if they so choose.—RJH (talk) 17:46, 3 June 2009 (UTC)

I'm relieved to know that Wikipedia does not engage in discrimination against non-human species. 72.134.97.155 (talk) 13:39, 4 August 2009 (UTC)

Number of humans to have been in space

In the last bit of the human geography section, it says 400 people have visited outer space as of 2004. As of 2009 it's closer to 500. —Preceding unsigned comment added by 84.246.11.153 (talk) 11:15, 23 July 2009 (UTC)

If you have a reliable source to serve as a citation, you're certainly welcome to update the text. But we can't just base it on word of mouth.—RJH (talk) 19:16, 23 July 2009 (UTC)

Future

I think the future section, in its exposition of when the oceans will evaporate, is giving undue weight to a single worst-case-scenario back-of-the-envelope calculation by a single professor at a shitty state college. —Preceding unsigned comment added by 76.85.197.106 (talk) 01:35, 17 July 2009 (UTC)

Well you are welcome to your opinion, but the wording of your argument gives it little if any credence. If you want to include alternative scenarios, you will need to gather and present suitable citations.—RJH (talk) 00:30, 19 July 2009 (UTC)

I agree with 76.85.197.106, something as important as the end of life on Earth, should be better documented, not by some calculations, that could be wrong for all we know.24.138.210.81 (talk) 08:20, 23 July 2009 (UTC)

Rational predictions of the future are all based on calculations, and yes they can all be wrong. Thus your statement doesn't seem helpful. Instead, please provide suitable citations that have greater weight.—RJH (talk) 19:17, 23 July 2009 (UTC)

Related information:

Sigurd (August 10, 2009). "On a cosmological timescale, The Earth's period of habitability is nearly over". Space Fellowship. Retrieved 2009-08-11.

based on an IAU symposium. Some interesting food for thought.—RJH (talk) 15:07, 11 August 2009 (UTC)

Contradiction in Section "Future"

The second paragraph states that life on Earth could possibly be extended up to 2.3Gyrs. The third paragraph talks about "most, if not all, remaining life" being destroyed when the sun becomes a red giant in 5Gyrs.

Both are supported by their sources. Perhaps the 3rd para needs to be rephrased using "any" or a subjunctive? AlmostReadytoFly (talk) 08:43, 12 August 2009 (UTC)

You're quite correct, of course. However, the source for the third paragraph only supports the change in the Earth's orbit; not the loss of life. I think it would make sense to remove the mention of life and add in some details about the likely loss of the atmosphere, if a suitable source can be found. Thanks.—15:36, 12 August 2009 (UTC)

1.0000175 yr?

I thought the definition of the year was the time Earth took to orbit the Sun. —Preceding unsigned comment added by 202.156.14.203 (talk) 14:36, 4 June 2009 (UTC)

Note that the "yr" is linked to Julian year (astronomy), which should give you the information you need. (The time Earth takes to orbit the Sun is slightly variable and also depends on when an orbit is considered to be completed, see Year#Astronomical years for definitions.) —JAO • T • C 14:58, 4 June 2009 (UTC)

I'm confused about the text in the article that says:
"Earth interacts with other objects in outer space, including the Sun and the Moon. At present, Earth orbits the Sun once for every roughly 366.26 times it rotates about its axis. This length of time is a sidereal year, which is equal to 365.26 solar days."
Why are the two numbers of days different (366.26 -vs- 365.26)? Ojm37a (talk) 16:57, 19 August 2009 (UTC)

Read the articles on sidereal year and solar days. LonelyMarble (talk) 17:20, 19 August 2009 (UTC)