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ToSeek
2004-Jun-04, 03:45 PM
Seeing the Very First Galaxies (http://skyandtelescope.com/news/article_1273_1.asp)


Using the largest telescopes in space and on Earth, various groups of astronomers are shedding new light on the dawn of the cosmos. The verdict so far: the "Dark Age" that followed the Big Bang probably lasted longer than thought and ended only gradually, with the first stars and galaxies lighting up the cosmos in fits and starts rather than in one nearly simultaneous, grand opening of light. Moreover, these very first stars may not have been as massive and brilliant as recently believed.

"To see the first stars and first galaxies has been the Holy Grail of cosmology for a long time," comments Space Telescope Science Institute director Steven Beckwith. "Right now, we’re beginning to see this."

Cougar
2004-Jun-05, 02:10 AM
...these very first stars may not have been as massive and brilliant as recently believed.


Aparna Venkatesan (University of Colorado) and Jason Tumlinson (University of Chicago) argued that the very first generation of stars in the universe — the "Population III" stars that presumably ended the Dark Age — may indeed have been less extreme than the 500-solar-mass behemoths of pure hydrogen and helium that astronomers have assumed they were. To explain both the ionization that took place in the early universe and the elemental composition of the second generation of stars, you need first-generation stars between 20 and 100 solar masses, they calculated.
Oh - they didn't have to be 500 solar mass stars, only 100 solar masses. That's still pretty big! I wonder how quickly such humongo-stars burn up their fuel and go superdupernova....

ChaosInc
2004-Jun-05, 02:51 PM
I have several questions on this that I thought someone could answer (keep in mind I am no scientist!). Wasn't there a Nobel awarded to the folks looking at background radio noise and found what was attributed to Big-Bang leftovers? If the red-shifted gas was the fisrt thing we can "see" then why haven't we seen what came after? I suppose that is what the people in the linked article are trying to do, but is it that we don't have the equipment or just aren't sure what to look for?

Padawan
2004-Jun-05, 06:28 PM
This seems to be an interesting article.

How massive could the earliest stars have been? Would there even be a difference between the current and the past average stellar masses?

Russ
2004-Jun-05, 06:54 PM
It's funny how information disapates into the world. :roll: I was just reading a Sci Am article yesterday, about some folk who had just found a galaxy at Z=10. They were claiming it had formed just 640 million yrs after TBB. Much sooner than anyone had thought possible, given the assumed lenght of the dark ages.

Hello Left Hand, I'd like to introduce you to the Right Hand. :lol: