Post by uriel on Feb 27, 2006 12:27:28 GMT -5
"The first stars were indeed very big, perhaps over 100 times more massive than our sun. They were also composed solely of the hydrogen and helium created in the big bang. These two features---very massive and pure---make them different from all the stars in existence today. The first stars were so big and hot that they burned blue, not yellow like our sun.
Let's start from the beginning---I mean, really the beginning. Scientists say that space, time and matter as we know it were created 13.7 billion years ago in a big bang. Another 200 million years would pass before stars formed. During much of this time, between the fireball of the big bang and the era of first starlight, the universe was steeped in darkness.
Star formation occurred when hydrogen and helium created in the big bang slowly condensed into gas clouds under the force of gravity. There were no other elements in the universe at this time aside from a tiny amount of lithium. That is, no oxygen, carbon or the other elements that make life possible.
When the cloud grew dense enough, high pressure and temperature initiated nuclear fusion in the cloud core, the signature of star birth..."
If you are interested in this article, please visit www.gsfc.nasa.gov/scienceques2005/20051114.htm
Let's start from the beginning---I mean, really the beginning. Scientists say that space, time and matter as we know it were created 13.7 billion years ago in a big bang. Another 200 million years would pass before stars formed. During much of this time, between the fireball of the big bang and the era of first starlight, the universe was steeped in darkness.
Star formation occurred when hydrogen and helium created in the big bang slowly condensed into gas clouds under the force of gravity. There were no other elements in the universe at this time aside from a tiny amount of lithium. That is, no oxygen, carbon or the other elements that make life possible.
When the cloud grew dense enough, high pressure and temperature initiated nuclear fusion in the cloud core, the signature of star birth..."
If you are interested in this article, please visit www.gsfc.nasa.gov/scienceques2005/20051114.htm
