Talk:List of stars with resolved images

Where does this list come from?

Is this original research? What is meant by "directly imaged"? I'm pretty sure that almost every star that we know of has been imaged...when I take my camera into my back yard at night, am I not imaging several stars?-RunningOnBrains 01:19, 7 January 2009 (UTC)

Good point. This needs an expert's attention, and I am so tagging it. Anyway, some of the info might be included in the main articles on the stars, although I did not find any size in arcminutes noted in the article about The Sun. GeorgeLouis (talk) 05:35, 30 August 2009 (UTC)

Requested move

The following discussion is an archived discussion of the proposal. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.

Page moved to List of stars with resolved images. Consensus was clear that there are significant issues with the current name. Even after keeping the discussion open for an extra week, no clear name came to the fore. So rather then leave the current name, I moved it to one of the names mentioned that seems to cover ideas in several proposals. Having done that, if there is a better name I have no objection to a followup nomination. I would suggest a discussion here to try and develop a consensus on a new name if the one I used is determined to be unacceptable prior to a new nomination. Vegaswikian (talk) 18:12, 2 July 2010 (UTC)

List of directly imaged stars → List of imaged stars — Relisted to see if there is a common name that gets consensus. Deletion is not a part of the discussion here but is for AfD. Vegaswikian (talk) 22:47, 22 June 2010 (UTC)

The word "directly" is not widely used by astronomers and only adds to the confusion. km5 (talk) 15:27, 11 June 2010 (UTC)

• Delete millions of stars have been photographed. 70.29.212.131 (talk) 03:09, 12 June 2010 (UTC)
• Comment: Given that the original title has proven confusing, I'd like to suggest List of stars whose images have been resolved. Spacepotato (talk) 20:11, 12 June 2010 (UTC)
• Comment—Yes, or perhaps a shorter name List of stellar angular diameters.—RJH (talk) 18:23, 15 June 2010 (UTC)
• Comment "List of stellar angular diameters" could potentially include predicted angular diameters from theoretical models, which does not seem to be the point of this page. How about List of stars with resolved images? Icalanise (talk) 18:20, 26 June 2010 (UTC)
• comment but what qualifies as a resolved image? perhaps list of observationally resolved stellar angular diameters ? 76.66.195.196 (talk) 12:44, 27 June 2010 (UTC)
  • comment I'd like to say something like "resolved disc" but there are some cases where "disc" would not be an appropriate term, e.g. the W Ursae Majoris variables (although I am not aware of any cases of a resolved W UMa system). Icalanise (talk) 21:27, 27 June 2010 (UTC)

Comment. Measuring an angular diameter is not the same as making an image of the disk of the star. For example, the first star to have its angular diameter measured was Betelgeuse, in 1920-21 by Michelson and Pease ([1][2]). However, the measurement was made interferometrically, by finding a zero of the visibility function, modeling the surface of the star by a uniformly illuminated disk, and then computing the diameter from the zero position. So, it gave no infomation whatever as to what the disk of the star looked like (it was simply assumed to be featureless.)

If the word "directly" is in the title of the list, there is also the question of what "direct" means. Images of Betelgeuse were made in the 1980s with interferometric data, for example, [3], and stellar images can also be constructed by Doppler imaging. However, according to Uitenbroek, Dupree and Gilliland doi:10.1086/300596, the first direct images of Betelgeuse were not taken until the 1990s, by the HST. Presumably for them "direct" means a telescopic image.

I don't think it's worth worrying about whether a 2-pixel image, etc., counts as an image. This is something that will be decided by the sources we quote (if they say they have an image, then they do.)

Spacepotato (talk) 23:56, 27 June 2010 (UTC)

Comment Pixels doesn't really have much to do with it: otherwise we could defocus our telescope to the required level to make it span as many pixels as we want (in fact, having stars spanning multiple pixels in the detector is often done when hunting for planetary transits). This is not the same thing as resolving the star however. Icalanise (talk) 20:18, 28 June 2010 (UTC)

Comment I meant pixels in the final, resolved, image, not pixels in the telescope focal plane. Anyway, I agree, it's not especially relevant. Spacepotato (talk) 20:29, 28 June 2010 (UTC)

The above discussion is preserved as an archive of the proposal. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.

Scope of the list

This list was proposed for deletion on the grounds that "millions of stars have been photographed". I removed the {{prod}} because this list is obviously supposed to contain stars whose images have been resolved beyond a point of light, i.e., those for which we have a picture of the disk of the star. This is not an endorsement of the current name of the article. Spacepotato (talk) 04:27, 12 June 2010 (UTC)

So this is a list of stars that have photographically resolved discs ? Which brings to question how many pixels makes a resolved disc. More than one = 2, not much of a disc there, or having been resolved. 70.29.212.131 (talk) 05:44, 12 June 2010 (UTC)

How many pixels does it take to resolve a disc-like image (in 2D) or a spheroid image (in 3D)? Two is obviously far from enough. Pbrower2a (talk) 12:59, 20 May 2014 (UTC)

No filter?

The Sun is "resolvable with the naked eye"

Brilliant! But maybe a bit too brilliant. 207.114.255.54 (talk) 20:44, 4 February 2013 (UTC)

Related deletion discussion

See Wikipedia:Articles for deletion/List of stellar angular diameters. One possible outcome of that AfD would be a merge here. —David Eppstein (talk) 19:47, 2 January 2015 (UTC)

For those curious, the page was moved to User:Nickshanks/List of stellar angular diameters. - CRGreathouse (t | c) 21:23, 2 March 2018 (UTC)

Angular diameter, Radius

Not all observations are made with the aim of determining angular diameter and radius. Often times multiple different telescopes and/or instruments imaged a single target. And finally: We already have the angular diameter and radius of each subject in their respective articles. So how do we handle these columns?

I presume original intend was to show measured diameter and radius, however often times sources do not show them, nor care about it. In these cases do we copy them from the article about the star? Or maybe in all cases we should simply copy the data out of star's infobox and let individual articles about the star display the history of its measurements? Or should we just dump these two columns all together? SkywalkerPL (talk) 12:34, 26 June 2017 (UTC)

Where are the resolved images?

This article lists the stars with resolved images, yet some images are missing. Where are they? 24.225.193.131 (talk) 14:16, 22 April 2019 (UTC)

The images must be under a free license to be used here. Ruslik_Zero 20:52, 22 April 2019 (UTC)

Is Proxima centauri resolved by Hubble or not?

The picture caption of the linked Hubble picture from proxima centauri says "Although by cosmic standards it is a close neighbour, Proxima Centauri remains a point-like object even using Hubble’s eagle-eyed vision, hinting at the vast scale of the Universe around us." This is in contradiction to this list. Who can resolve that conundrum? --188.22.166.56 (talk) 17:07, 8 February 2020 (UTC)

Add Achernar?

Does Achernar meet the criteria for inclusion? According to [4], the degree of oblateness has been measured. Kid222r (talk) 19:52, 27 March 2021 (UTC)

Black holes

What about the black holes that have been imaged somewhat directly such as that one? Black holes are stellar remnants, technically dead stars. The stellar remnant itself may be a singularity hidden inside the event horizon, but the diameters of the event horizons have been resolved to more than a dot. 2001:4BC9:1F9A:468:485F:1D71:BF4F:1859 (talk) 12:55, 17 October 2023 (UTC)

Black holes are not stars. Tercer (talk) 13:01, 17 October 2023 (UTC)

Yes, they are, respectively the singularity or quark star inside the event horizon. And substellar bodies orbiting them are referred to as planets. 2001:4BC9:1F98:C33D:B5B2:BE0B:5A48:2696 (talk) 15:55, 18 October 2023 (UTC)

Hmm. I don't think black holes are a good fit for this article, but perhaps it's worth another article considering that two have been imaged and likely others will be as well. What do you think would be the best scope for another article? Specific to black holes, or broader? - CRGreathouse (t | c) 13:04, 20 October 2023 (UTC)

So far, only two images have been made of black holes; as long as there aren't considerably more I don't believe there should be an article on it yet. In any case, it needs to be stated in this article that it excludes black holes (or all stellar remnants?). 2001:4BC9:1F98:9156:99AF:AC51:82C0:8926 (talk) 09:54, 26 October 2023 (UTC)

The article has "star" in the title, and links to Star, which defines them as such:

A star is an astronomical object comprising a luminous spheroid of plasma held together by self-gravity.

I think this is adequate for our purpose, and does exclude black holes.

CRGreathouse (t | c) 03:34, 27 October 2023 (UTC)

A star is a celestial body whose mass and density are or were large enough to cause or have caused the fusion of deuterium, lithium or hydrogen. This includes stellar remnants including black holes. The singularity is inside the event horizon which is why it can't emit light escaping to event horizon, though perhaps it might escape through a white hole elsewhere in space, thereby forming an Einstein Rosen Bridge. A black hole also emits Hawking radiation, and may have a luminous accretion disc. 2001:4BC9:1F9A:1F64:59D:B56D:3859:ADA8 (talk) 06:20, 27 October 2023 (UTC)

By almost any definition, black holes are not stars. A stellar remnant does not necessarily qualify as a star. Plus, supermassive black holes accrete their mass from so many different sources (many stars and small black holes) that I’m not even sure if they qualify as stellar remnants.

There’s no thermonuclear fusion. There’s no luminosity (that it produces itself, unless you count Hawking Radiation, which is a stretch). There’s no plasma. It’s just an unimaginable amount of mass concentrated in an infinitely small space. It doesn’t have the properties of a star. Opportunity Rover (talk) 04:02, 25 March 2024 (UTC)