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Fraser
2005-Sep-22, 07:49 PM
SUMMARY: By looking at the most distant Universe, astronomers are hoping to learn what kinds of galaxies formed first, leading through mergers to the mature galaxies we see today. The more galaxies you look at, the better the predictions. A team of French and Italian astronomers have used the VIsible Multi-Object Spectrograph (VIMOS) instrument on one of the ESO's 8.2 m telescopes to image and measure thousands of galaxies. They found 2 to 6 times as many early galaxies with vigorous star formation than astronomers had previously expected.

View full article (http://www.universetoday.com/am/publish/many_galaxies_early_universe.html)
What do you think about this story? post your comments below.

cran
2005-Sep-22, 11:53 PM
["This discovery implies that galaxies formed many more stars early in the life of the Universe than had previously been thought", explains Gianpaolo Vettolani, the other co-leader of the VVDS project, working at INAF-IRA in Bologna (Italy). "These observations will demand a profound reassessment of our theories of the formation and evolution of galaxies in a changing Universe."

It now remains for astronomers to explain how one can create such a large population of galaxies, producing more stars than previously assumed, at a time when the Universe was about 10-20% of its current age.] - from the article.

Sums it up fairly well, I think. :)

I am continually given reasons to be thankful to be alive in this era of discovery... :)

Fr. Wayne
2005-Sep-23, 09:39 AM
What my question is: How can scientists assume that the most distant galaxies are the earliest? Just because we receive their light from so far away? The first galaxies may not necessarily be so distant. Data from most distant objects cetainly travel the farthest we know of, but this assumes a 13 billion year journey with no modifications during that whole time. As exciting as the data is, I believe it is too big of an assumption to take for granted thes photons are tamper-proof given their long trek. :question:

bigsplit
2005-Sep-23, 03:00 PM
What my question is: How can scientists assume that the most distant galaxies are the earliest? Just because we receive their light from so far away? The first galaxies may not necessarily be so distant. Data from most distant objects cetainly travel the farthest we know of, but this assumes a 13 billion year journey with no modifications during that whole time. As exciting as the data is, I believe it is too big of an assumption to take for granted thes photons are tamper-proof given their long trek. :question:

When the spherical Universe existed the oldest stars were in the center. But when the center moved to the edge to generate the funnel see

http://www.newscientist.com/article.ns?id=dn4879

the galaxies were all mixed up.

suitti
2005-Sep-23, 05:38 PM
My current favorite online cosmology overview articles are:
http://www.sciam.com/article.cfm?chanID=sa007&articleID=0009F0CA-C523-1213-852383414B7F0147
and the more recent
http://physicsweb.org/articles/world/18/9/3
I don't think either is complete, and it doesn't seem likely that they agree with each other.

I found my keys. They were right where I put them. No big deal.
These astronomers found whole galaxies! Astronomers are pretty impressive, but how can anyone misplace a whole galaxy?

bigsplit
2005-Sep-23, 07:06 PM
What would the CMB look like I wonder if it did start out as a spherical dodecahedral and evolved into a picard funnel. And the octohedral and tetrahedral were phases of the transition, so they all may work out. Now if we could analyse that posibility and generate an extremely dynamic and complexed evolution of the Universe we would be getting somewhere.

Jerry
2005-Sep-23, 09:28 PM
So we looked more closely and found many more galaxies than evolutionary models predicted.

Again.

Greg
2005-Sep-27, 03:11 AM
Somehow I am not surprised. I have always prefered to believe in models predicting more galaxies in this early epoch of the universe. My reasoning is that when you have the same amount of mass constrained in a much more compact volume of space that it would be easier for it to get together. After all the strength of gravity varies according to the square of the distance. It would seem logical to me that the effect of mass being less spread out would overcome any initial uniformity in its distribution. Also perhaps the earliest distribution of matter was less uniform (and more clumped) than previously believed.