Friday, November 19, 2010

'We're looking almost to the edge'

Oldest Galaxy Discovered From 13.1 Billion Years Ago, Astronomers Say

AP: Hidden in a Hubble Space Telescope photo released earlier this year is a small smudge of light that European astronomers now calculate is a galaxy from 13.1 billion years ago. That's a time when the universe was very young, just shy of 600 million years old. That would make it the earliest and most distant galaxy seen so far.

By now the galaxy is so ancient it probably doesn't exist in its earlier form and has already merged into bigger neighbors, said Matthew Lehnert of the Paris Observatory, lead author of the study published online in the journal Nature. 'We're looking at the universe when it was a 20th of its current age,' said California Institute of Technology astronomy professor Richard Ellis...

'Because it takes so long for the light to travel such a vast time and distance, astronomers are seeing what the galaxy looked like... at a time when it was quite young -- maybe even as young as 100 million years old,' Lehnert said. 'It has very little of the carbon or metal that we see in more mature stars and is full of young, blue massive stars.'

What's most interesting to astronomers is that this finding fits with theories about when the first stars and galaxies were born. This galaxy would have formed not too soon after them. 'We're looking almost to the edge, almost within 100 million years of seeing the very first objects,' Ellis said.
Image source here; galaxy described is small smudge at centre.