Galaxy Has 1,000 Times Our Rate of Star Formation
Written by Fraser Cain
Here in the Milky Way, new stars are formed at a rate of roughly 4 per year; that's considered pretty normal for spiral galaxy like ours. But researchers have found a galaxy that's absolutely bursting with new star formation. Instead of our leisurely 4 stars per year, this distant galaxy is generating more than 4,000 new stars a year.
The galaxy, known at GOODS 850-5, is located about 12 billion light-years from Earth. This means that astronomers are seeing the light coming from it at a point when the Universe was only 1.5 billion years old.
All of the star formation in this galaxy was obscured by thick layers of dust, emitted by all the stellar nurseries. This means they're hidden by visible-light telescopes.
By using the Smithsonian Astrophysical Observatory's Submillimeter Array (SMA) on Mauna Kea in Hawaii, the researchers were able to peer right through the obscuring dust to calculate the rate of star formation.
The irony is that the dust from all that star formation was obscuring the, uh, star formation. Here's Wei-Hao Wang, one of the astronomers who worked on the research:
"This evidence for prolific star formation is hidden by the dust from visible-light telescopes," Wang explained. The dust, in turn, was formed from heavy elements that had to be built up in the cores of earlier stars. This indicates, Wang said, that significant numbers of stars already had formed, then spewed those heavy elements into interstellar space through supernova explosions and stellar winds.
This discovery has come as a bit of a surprise, since astronomers used to think that the most actively star forming galaxies would be smaller and less obscured. Now they're starting to realize that it's actually the big dusty galaxies that form the most stars. We just couldn't see it.
For a galaxy to be experiencing this much star formation, it must have gone through many rounds of mergers with other galaxies. And this is also surprising, considering it's only 1.5 billion years old in the image.
Original Source: NRAO News Release
Filed under: Astronomy
December 20th, 2007 at 6:31 am
"All of the star formation in this galaxy was obscured by thick layers of dust, emitted by all the stellar nurseries. This means they're hidden by visible-light telescopes."
Wow, that's a lot of telescopes. The entire population of the galaxy must be astronomers.
December 20th, 2007 at 6:59 am
[...]"This evidence for prolific star formation is hidden by the dust from visible-light telescopes," Wang explained.[...]
And those lots of telescopes are dirty ones, too!
December 20th, 2007 at 10:20 am
The first 2 or 3 comments, by other posters, to this story seem to have disappeared, at least for this poster (1220 EST, 12/20/2007). More serious than my first post above, they all said about the same thing, 'Nice bit of research", which is certainly true. If the results are confirmed by other researchers and are generally applicable, some revisions in our ideas of galaxy formation may be in order.
December 20th, 2007 at 9:36 pm
Fantasic! I never get tired of learning about
our physical universe and beyond!
The Bible describes the
Designer of it as "the true God, Jehovah".
Isaiah 42:5 says: "This is what the [true] God,
Jehovah, has said, the Creator of the heavens
and the Grand One stretching them out; the One laying out the earth and its produce,the One giving breath to the people on it, and spirit to those walking in it."
Ms. S.M.Supka
December 24th, 2007 at 12:01 am
I predicted that stellar birth rates would be higher in early galaxies. The energy production of quasars is accelerated stellar physics. The effect of gravity varies due to the change in density of systems. Expansion includes the spacetime between the atoms. A denser star would evolve faster with less mass.
December 24th, 2007 at 4:02 am
interesting newsletter
January 22nd, 2008 at 8:29 pm
[...] New View of Distant Galaxy Reveals Furious Star Formation• Galaxy Has 1,000 Times Our Rate of Star Formation• GOODS 850-5 — A z>4 Galaxy Discovered in the [...]