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Fraser
2005-Jan-14, 04:52 PM
SUMMARY: A researcher from Indiana University Bloomington has discovered what could be primordial hydrogen, unchanged since the Big Bang. This hydrogen was found in galaxy UGC 5288, located 16 million light years away from Earth. When studied with the National Science Foundation's Very Large Array radio telescope in New Mexico, the galaxy seems to be surrounded by a huge disk of hydrogen gas. This could be a place to examine pristine hydrogen that hasn't been "polluted" by heavier elements created in stars.

View full article (http://www.universetoday.com/am/publish/leftover_big_bang.html)

What do you think about this story? Post your comments below.

antoniseb
2005-Jan-14, 05:02 PM
This is one of several stories we've had here in the last few weeks about 'primordial material' to various degrees, all showing something about how galaxies, and the first stars formed. This is a pretty hot topic of research right now, and we should expect to see more about this kind of thing over the next few years.

This is another galaxy that the SKA will be very useful in studying, especially mapping the velocities of the various sections of the Hydrogen cloud as it falls into, or orbits the central small galaxy.

Keith Nealy
2005-Jan-15, 12:39 AM
Can someone explain the difference between "pristine" hydrogen, and "polluted" hydrogen? I thought hydrogen was hydrogen, -one proton, one electron. How can it be pristine or polluted?

antoniseb
2005-Jan-15, 12:44 AM
Originally posted by Keith Nealy@Jan 15 2005, 12:39 AM
Can someone explain the difference between "pristine" hydrogen, and "polluted" hydrogen? I thought hydrogen was hydrogen, -one proton, one electron. How can it be pristine or polluted?
It's not so much that any one atom is polluted. In this case the so called pristine clouds of gas are thought to be little changed since the days of the Cosmic Microwave Background, as opposed to clouds of gas [mostly Hydrogen, with some Deuterium, He3, He4, and Li7] blown into elliptical orbit around a galaxy by a series of supernova explosions in a stellar nursery or some other mechanism for moving clouds of gas that involves putting nucleosynthesis products into the mix.

Guest
2005-Jan-15, 07:41 AM
I see. So it's really a pristine or polluted cloud or nebula, not hydrogen.

Thanks for the assistance.