Talk:Elliptical galaxy

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Wiki Education Foundation-supported course assignment[edit]

This article is or was the subject of a Wiki Education Foundation-supported course assignment. Further details are available on the course page. Student editor(s): Ahanania. Peer reviewers: Kg5601.

Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 20:28, 16 January 2022 (UTC)[reply]

spiral[edit]

the spiral galaxy is sometimes in between the 3 main categories.

Size?[edit]

The sentance "There is a wide range in size and mass for elliptical galaxies: as small as a tenth of a kiloparsec to over 100 kiloparsecs..." is confusing. Does this mean that the diameter ranges from a tenth of a kiloparsec to over 100 kiloparsecs?

Vsst 03:28, 20 April 2007 (UTC)[reply]

Just an order of magnitude estimate - there's no unique 'diameter' unless the galaxy is spherical anyway.

User:EGetzler May, 2012

That wasn't the question. It was a reference to the use of the poor expression "size and mass"
There is an online textbook that displays a table for Elliptical galaxies that might be helpful. [1]Ahanania (talk) 00:11, 22 January 2017 (UTC)[reply]

References

Elliptical fraction[edit]

The figure of 70% quoted in the intro was completely wrong: ellipticals make up around 10-15% of galaxies in the field in the local universe. Even in the centers of clusters (where ellipticals are more common) it only rises to ~40%. I've corrected it. Cosmo0 16:46, 15 September 2007 (UTC)[reply]

"They are preferentially found close to the centers of galaxy clusters[3] and are less common in the early Universe."

M87 the Largest Known Galaxy?[edit]

No, it's not actually. IC 1101 may be. http://startswithabang.com/?p=952

Random Jibberish MUST FIX[edit]

I am finding spam from spambots edit it now. — Preceding unsigned comment added by 173.49.151.155 (talk) 14:31, 17 October 2013 (UTC)[reply]

How is this a top important article?[edit]

Just wondering. It receives on average 10 views a day only Tetra quark (talk) 19:19, 29 December 2014 (UTC)[reply]

Nope, it's received nearly 10000 views so far this month [1]. Also, view count is definitely correlated with importance, but I'd imagine if I did a regression and found the R-squared value, it would be quite low. StringTheory11 (t • c) 20:34, 29 December 2014 (UTC)[reply]

'Evolution' section, plus explaining my minor edits[edit]

Hi people,

I added a tag requesting more inline citations, for the whole article. Quite a few of the paragraphs are plagued by this, and at times it is not clear which citation relates to which (and how many) sentences.

It seemed (to me at least) that someone went a bit gang ho with the Ho textbook. If someone believes that they can dig in to it, extract SPECIFIC citations from that book that back up claims and return here and add them to said claims, by all means please do it. But until this is done, wherever I see sentences along the lines of "it is believed that" and then dropping a blanket ISBN code, I will keep asking for more specific citations.

Finally, I added that elliptics are an active area of research (because it is) and an unsolved problem in physics (because it is). If someone knows a tag/template for this please add it. Furthermore, I am asking for a better source for Milky Way on its way to collide with Andromeda. Nice nasa picture, sure, and makes a fancy headline, allright, but wikipedia is neither a fancy headline factory nor a fancy picture collection. If someone claims that Milky Way is on a collision course with Andromeda, I would like to see vectors, math, and perhaps an arxiv paper or two.

I think this makes sense,

C4 yourself (talk) 23:44, 13 March 2015 (UTC)[reply]

Also in the citation, I do not think phrase, "It is believed that black holes..." should be in this section. It is a general phrase with no citation.Ahanania (talk) 00:16, 22 January 2017 (UTC)[reply]

Compact elliptical galaxies[edit]

Are these articles of interest to this article? The news article and study article describe how a compact elliptical galaxy may be sent into space after interaction with the gravity of 2 other galaxies. news.nationalgeographic.com 2015-04-23 How a Galaxy Can Get Booted From Its Home www.sciencemag.org April 2015 Isolated compact elliptical galaxies: Stellar systems that ran awayJcardazzi (talk) 15:09, 24 April 2015 (UTC)jcardazzi[reply]

What IS  the diffuse glow of elliptical galaxies?[edit]

I haven't found an actual source that explicitly states the most salient visual feature of M87, IC 1101, etc. The bodies of the galaxies appear, almost entirely, to a layperson to consist of that luminous mass. So what is it? Bits and pieces of info suggest ellipticals are strongly deficient in dust and gas, but then other sources suggest otherwise. If there's a sufficiency of dust and gas, is it irradiated dust that is glowing? Is it ionized gas excited by irradiation from the black-hole's accretion disk? or from the stellar winds of the aggregate billions (and even trillions) of constituent stars? Is that body of luminescence those very stars themselves—that is to say, when you're looking at that glow, you are looking at its very stars themselves—irresolvable by any telescope? Or a combination of those factors?

This seems to me to be an absurdly elementary and obvious question that shouldn't even need to be asked. Any basic description of the sun will quickly get to the photosphere, the corona, etc. and spell out their contributions to that radiant orb in the sky. JohndanR (talk) 22:56, 22 May 2018 (UTC)[reply]

It's just the stars. You're seeing the combined light of many billions of stars within the galaxy. If that's not sufficiently clear from the article then maybe a brief statement to that effect could be added somewhere. Aldebarium (talk) 15:19, 24 May 2018 (UTC)[reply]

Late type[edit]

The terms "late type galaxy" and "early type galaxy" appear in various articles including this one. In what article is the distinction discussed? We should link to it. Jim.henderson (talk) 01:50, 16 March 2022 (UTC)[reply]

Incorrect with regard to Hubble evolutionary belief[edit]

This article states: "Originally, Edwin Hubble hypothesized that elliptical galaxies evolved into spiral galaxies..." However, the "Hubble sequence" article states that "This nomenclature is the source of the common, but erroneous, belief that the Hubble sequence was intended to reflect a supposed evolutionary sequence...", and even features a cited quote from Hubble himself. Needs correcting. 188.147.108.144 (talk) 10:53, 6 October 2023 (UTC)[reply]