Talk:Dwarf galaxy

Why the list?

The list included in the article seems redundant, at least to me. People looking for dwarf galaxies can click the category and find them all there. __meco (talk) 09:57, 8 April 2008 (UTC)

I think a short list of examples is appropriate to illustrate the subject matter of the article, but it might be a good idea to thin this one out (half a dozen should be sufficient, e.g. spiral galaxy has only 5 well-known examples and elliptical galaxy has only 7). Cosmo0 (talk) 19:08, 8 April 2008 (UTC)

It could be split off into an article of its own... 70.51.11.14 (talk) 06:17, 31 July 2008 (UTC)

Upcoming major edit

Just a quick note to let everyone know. The Astronomy 533 graduate astronomy class at the University of Michigan is updating a small number of astronomy-related wiki pages, this is one of them. The page will be significantly changed; please feel free to have a look when it comes online in mid-December. EFBell (talk) 20:40, 18 November 2010 (UTC)

Thoughts

The tidal theory of dwarf galaxy formation proposed by Kroupa is not supported by the major of people who work in dwarf galaxies.

The community is divided on whether ultra compact dwarfs are small galaxies or large globular clusters.

While Hobbit galaxy was used in a press release the term ultra faint dwarf is much more common in the literature. Korandder (talk) 11:38, 21 September 2011 (UTC)

According to Galaxy Formation and Evolution by Mo & van den Bosch (pg.58); and to: http://www.eso.org/sci/meetings/2011/dynamics2011/Contributions/Neumayer.pdf; "Ultra Compact Dwarves (UCD)" are qualitatively distinct from dwarf (Spheroidal & Elliptical) galaxies: plotted in the phase spaces of radius vs. absolute brightness, and surface brightness vs. mass, UCD reside in distinct regions of those phase spaces. According to: http://iopscience.iop.org/2041-8205/724/1/L64/fulltext/apjl_724_1_64.text.html; UCDs are typically older and more metal poor than dwarf Elliptical nuclei. Inexpertly, UCDs resemble large Globular Clusters (GC), in age, metallicity, mass, size, and luminosity; and do not resemble, in detail, small galaxies. Perhaps these provided sources could help improve this article.

(quick question — if UCDs represent the biggest & brightest GCs; and since UCDs also resemble "Nuclear [Star] Clusters (NC)" at the centers of most galaxies (ESO article), so forming the nuclei of most galaxies; then there might be a connection between GC / UCDs, and NCs embedded within their larger spheroidal galactic halos. And if so, then why don't GC / UCD have surrounding stellar halos? Or what happened to them? Is that why some scientists sense that UCDs have been stripped of outer-lying halos of stars?) 66.235.38.214 (talk) 04:20, 12 November 2012 (UTC)

According to Mo & van den Bosch (pp.59-60), UCDs in isolation, resemble NC embedded in the centers of spheroidal ("Ellipsoidal?") galactic components (Elliptical galaxies, Spiral bulges). And, compact Ellipticals (cE) in isolation, resemble Spiral bulges embedded in Spiral disks. So, there seems to be a common concept of "embedding", whereby similar astro-galactic objects can exist in isolation, or embedded within larger surrounding systems. These logical connections seem valid; perhaps some specialist in the field knows some professional sources to cite, and with which to update and so improve the coverage of this article ? For example, there seems to be some sense that some UCDs have been stripped of surrounding stars; perhaps such "stripping" is the (logical) inverse of "embedding" ? 66.235.38.214 (talk) 05:13, 12 November 2012 (UTC)

Ultra-compact dwarfs

I created M59-UCD3 because I thought it notable being the densest galaxy to date. there are now a number of them but I'm not sure about whether I should add all of them as separate articles or just notable ones? Also, these galaxies are readily visible on a number of photographs. M59-UCD3 is visible on the M59 infobox picture. I can lift the picture from here [1] or create one myself but I don't like the low resolution of the M59 picture. thoughts? --DHeyward (talk) 21:03, 29 July 2015 (UTC)

See WP:NASTRO for guidance. A list of ultra-compact dwarfs may be more appropriate. Headbomb {talk / contribs / physics / books} 02:09, 30 July 2015 (UTC)