Wikipedia:Reference desk/Archives/Miscellaneous/2011 May 13

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May 13

Diesel Engine

Would a diesel engine, such as those on backhoes or wheel loaders, work on the moon or could one be modified to work? Sumsum2010·T·C 05:05, 13 May 2011 (UTC)

The four major differences would be the reduced gravity, lack of oxygen, lack of air pressure, and temperature range:

1) I don't see gravity being much of a problem, and even if it was, an electric pump could be used to deliver fuel more rapidly.

2) The lack of oxygen is a serious problem. You'd need to supply that in oxygen cylinders to get combustion.

3) Lack of air pressure might cause the engine to overheat, as a fan wouldn't work to cool it. Instead, you'd need to provide a heat sink which could radiate the heat away. This might be very large.

4) The temperature on the Moon can get quite cold, so you'd need to heat the engine up electrically before it would start. It can also get quite hot, at least in the sunlight. Perhaps putting it in shade would solve that, say by building a shelter over it.

So, it could work, but I doubt if it would be practical. The thing that makes it most impractical is weight. You'd need to bring the engine, the heat sink, the diesel fuel, the shelter, and the oxygen all from Earth, at extreme cost. Nuclear power can provide energy for far less weight, on an unmanned mission, where radiation isn't a concern. For a manned mission, perhaps solar cells and batteries are best. StuRat (talk) 07:04, 13 May 2011 (UTC)

Thanks for the detailed response! I had been watching a TV show about mining and minerals on other planets, so I wondered if conventional engines could be used to mine these minerals. Sumsum2010·T·C 22:25, 13 May 2011 (UTC)

StuRat's answer is very good, but I want to emphasize that the real issue is a lack of oxygen. Diesels work by burning fossil fuels (or some other appropriate combustible liquid like vegetable oil). This is easy enough to do on earth with the oxygen that is present in the air. In a vacuum this is impossible, you would need to bring your supply of oxygen and other gases with which to mix it (100% O2 wouldn't work at least with current designs) which is far more complicated than an electric motor and a battery (charged by solar or whatever). --Daniel 05:46, 14 May 2011 (UTC)

I thought of another issue. The temperature extremes could damage the engine, while in storage, due to thermal expansion and contraction. Thus, it would need to be stored in a temperature controlled environment, not just left "outside".

Something else to consider is the dust on the Moon. This would be bad, if it got into the engine. However, since you wouldn't be using the atmosphere for combustion as on Earth, but rather would have bottled "air" fed into it, keeping the dust out shouldn't be a problem. StuRat (talk) 06:46, 14 May 2011 (UTC)

Assuming you can get the fuel and oxygen, you would still have to do something with the exhaust gases. Astronaut (talk) 10:12, 14 May 2011 (UTC)

Why? Just vent it. Not having outside pressure should even somewhat improve efficiency. Of course, if you use an Earthly design, you might need to run it in a pressurised enclosure. Otherwise, the lubricants are bound to evaporate off too quickly. --Stephan Schulz (talk) 17:03, 14 May 2011 (UTC)

I wouldn't worry about it myself, but I suppose there could be environmentalists concerned about the effect of venting exhaust gases. (It might make the area around the engine get all sooty, if it precipitates back down.) StuRat (talk) 22:40, 14 May 2011 (UTC)

internal voice

is there a god? is there a ghost? —Preceding unsigned comment added by 180.215.177.130 (talk) 06:45, 13 May 2011 (UTC)

No. HiLo48 (talk) 06:54, 13 May 2011 (UTC)

On the other hand, there might be. HiLo48 (talk) 06:55, 13 May 2011 (UTC)

God(s) and ghost(s) have subjective reality for many people while others are not sure. Some like HiLo48 begin by being sure and then wonder whether they were right. Cuddlyable3 (talk) 10:41, 13 May 2011 (UTC)

Obligatory links: God, Ghost. --Colapeninsula (talk) 11:26, 13 May 2011 (UTC)

These are things that are by nature, or at least have to the present, been more or less unverifiable. This is the realm where science has not been very useful, as it has been no more successful at proving their existences than disproving. I tend not to believe in ghosts, but my roommate is convinced that they exist. I think on both counts, especially with "is there a god", you have to decide for yourself. I cannot provide much evidence to support or refute the existence, though I do have a very strong belief surrounding that (I won't say right now whether that belief is for or against the existence). One thing of note, according to the Wikipedia Article Near-death experiences, some scientists find the phenomenon as evidence of an afterlife. Others believe that there are purely biological explanations. Who's right? We do not know yet. Falconus^{p t c} 16:16, 13 May 2011 (UTC)

Also note: internal narrator, verbal thinking, self-awareness, conscience, consciousness, soul. 86.164.60.255 (talk) 20:46, 13 May 2011 (UTC)

@Cuddylable3:Please do not resort to personal attacks,chides or comments.Personal attacks violate Wikipedia policy.Thank you. Pseudo 10:48, 14 May 2011 (UTC)

This has no basis, Pseudo. Cuddlyable3's comment was not inappropriate, and most certainly not an attack on anyone. -- Jack of Oz [your turn] 18:38, 14 May 2011 (UTC)

Agreed... I thought it a very clever response to the question using HiLo48's (intentional?) indecisiveness as an example... gazhiley.co.uk 13:20, 17 May 2011 (UTC)

NATA Exam

PLZ INFORM ME WITH THE SUBJECS REQUIRED FOR THE NATA EXAM AND IS IT POSSIBLE TO TAKE B.ARC BY AIEEE OR IIT ?? —Preceding unsigned comment added by 115.118.182.162 (talk) 08:55, 13 May 2011 (UTC)

Click here for information about the National Aptitude Test in Architecture NATA Exam. Please don't write in CAPITAL letters because that is understood as shouting! Cuddlyable3 (talk) 10:39, 13 May 2011 (UTC)

2 question about Northern Canada

1. What is the most northern community in the North-West_Territories Canada? 2. I was looking for a website for Grise_Fiord Nunavut but I couldn't find one. Also can anyone name any notable people from [[Grise_Fiord]? Like as in Politician or something? Thanks! Neptunekh2 (talk) 14:10, 13 May 2011 (UTC)

From List of communities in the Northwest Territories, it would appear to be Sachs Harbour. --jpgordon^{::==( o )} 15:39, 13 May 2011 (UTC)

Larry Audlaluk was awarded the Order of Canada, Looty Pijamini is an artist from Grise and there are some descendants of Robert J. Flaherty (Nanook of the North) such as Martha Flaherty. Then there is Florin Fodor who isn't from there but has "visited" the place. CambridgeBayWeather (talk) 05:31, 14 May 2011 (UTC)

Neptunekh2, as it says above, "Please, post your question on only one section of the reference desk." (I have just posted this warning on the Humanities Desk.) BrainyBabe (talk) 10:13, 14 May 2011 (UTC)

Peligre Dam

How has the dam on the Artibonite River in Haiti suffered from the earthquake? Could it collapse? 71.194.255.203 (talk) 19:00, 13 May 2011 (UTC)

According to this factsheet issued by the United States Agency for International Development in February this year, ongoing projects include: "rehabilitation of a dam damaged by the earthquake on the Maury River — a tributary of the Artibonite River. USAID/OFDA staff visited the rehabilitated dam and spoke with beneficiaries, who noted that the irrigation system fed by the dam will help 800 people increase their cultivatable area and improve crop output, generating income for local agricultural workers and increasing food availability in the area." So the answer to your question seems to be no, it's not likely to collapse. Alansplodge (talk) 18:52, 14 May 2011 (UTC)

Old English Coin

I have a copper coin, about 2 cm in diameter. On one side is a soldier on a horse with the words "To Hanover" above him and "1837" below him. On the reverse side is a portrait of Queen Victoria and the words "Victoria Regina" and, below the portrait, "1852". What is this coin and what is its approximate value ? 76.21.184.228 (talk) 19:11, 13 May 2011 (UTC)

This site suggests it's probably a 'To Hanover' coin[1] - the suggestion in that forum is about $2-10. Searching on eBay suggests it's worth around that much, potentially a little more[2]. ny156uk (talk) 19:30, 13 May 2011 (UTC)