Post by glactus on Sept 22, 2008 9:18:27 GMT
NASA's Swift satellite captured the most distant gamma-ray burst ever detected. The blast came from an exploding star 12.8 billion light-years away, near the edge of the visible universe.
Swift saw the explosion on September 13 at 1:47 am EDT. but because light moves at finite speed, and looking farther into the universe means looking back in time, this means the burst occurred less than 825 million years after the universe began, or when the universe was less than one-seventh its present age.
This star was probably from the earliest generations of stars ever formed. "This is the most amazing burst Swift has seen," said the mission's lead scientist Neil Gehrels at NASA's Goddard Space Flight Center.
Gamma-ray bursts are the universe's most luminous explosions. Most occur when massive stars run out of nuclear fuel. As their cores collapse into a black hole or neutron star, gas jets — driven by processes not fully understood — punch through the star and blast into space. There, they strike gas previously shed by the star and heat it, which generates bright afterglows.
Credits: Gamma ray burst image by NASA
This is part text only: See image, full text and all scientists involved at universetoday.com.
www.universetoday.com/2008/09/20/gamma-ray-burst-from-the-edge-of-the-universe/
Article presenter: Nancy Atkinson