CraigS
12-08-2010, 08:06 AM
In this morning's news (journo's article only):
Giant ultraviolet rings found in resurrected galaxies
http://www.physorg.com/news200757794.html
"Astronomers have found mysterious, giant loops of ultraviolet light in aged, massive galaxies, which seem to have a second lease on life. Somehow these "over-the-hill galaxies" have been infused with fresh gas to form new stars that power these truly gargantuan rings, some of which could encircle several Milky Way galaxies.
...
The Galaxy Evolution Explorer could not discern the fine details of these large, rounded galaxies gleaming in the ultraviolet, so to get a closer look, researchers turned to the Hubble Space Telescope. What they saw shocked them: three-quarters of the galaxies were spanned by great, shining rings of ultraviolet light, with some ripples stretching 250,000 light-years. A few galaxies even had spiral-shaped ultraviolet features.
"We haven't seen anything quite like these rings before," said Michael Rich, co-author of the paper and a research astronomer at UCLA. "These beautiful and very unusual objects might be telling us something very important about the evolution of galaxies."
Baryonic material (gas) seems to be their conclusion .. 250,000 light years across !! I wonder how this compares with the galaxies' impact parameter ... that is, if they could capture a lens effect from one of them ...
Cheers
Giant ultraviolet rings found in resurrected galaxies
http://www.physorg.com/news200757794.html
"Astronomers have found mysterious, giant loops of ultraviolet light in aged, massive galaxies, which seem to have a second lease on life. Somehow these "over-the-hill galaxies" have been infused with fresh gas to form new stars that power these truly gargantuan rings, some of which could encircle several Milky Way galaxies.
...
The Galaxy Evolution Explorer could not discern the fine details of these large, rounded galaxies gleaming in the ultraviolet, so to get a closer look, researchers turned to the Hubble Space Telescope. What they saw shocked them: three-quarters of the galaxies were spanned by great, shining rings of ultraviolet light, with some ripples stretching 250,000 light-years. A few galaxies even had spiral-shaped ultraviolet features.
"We haven't seen anything quite like these rings before," said Michael Rich, co-author of the paper and a research astronomer at UCLA. "These beautiful and very unusual objects might be telling us something very important about the evolution of galaxies."
Baryonic material (gas) seems to be their conclusion .. 250,000 light years across !! I wonder how this compares with the galaxies' impact parameter ... that is, if they could capture a lens effect from one of them ...
Cheers