Galaxy Zoo Talk

Re : Cloud like galaxy.

  • suelaine by suelaine

    This galaxy looks as though it is at the end of its life, but if is starforming then, I assume that is indeed active. Can someone tell me about these cloud-like galaxies.


  • JeanTate by JeanTate

    They are irregulars, dwarf galaxies with lots of dark matter, some gas, and recent star-formation. They have 'low metalicity', meaning that the relative abundance of all elements (other than helium), when compared to hydrogen, is much lower than it is for our own galaxy, because they have had few cycles of star-formation, possibly only one.

    Because they're rather diffuse and faint, they're hard to see much beyond the Virgo cluster (the nearest galaxy cluster; we are likely on its outer edge), but they could be the most common kind of galaxy in the whole universe. As far as I know, they're not studied much.


  • JeanTate by JeanTate in response to JeanTate's comment.

    UPDATE: Following the links, this dwarf has a redshift of 0.005 (so it is very local), and is also known as [GBM2006] 227294. The "GBM2006" refers to a 2006 paper by M. Geha, M. R. Blanton, M. Masjedi, and A. A. West, "The Baryon Content of Extremely Low Mass Dwarf Galaxies". It's a pretty good paper, judging solely by the number of other papers which have cited it (118).

    Maybe I was wrong; maybe dwarf galaxies like this have, in fact, been studied rather intensively.