Astronomy Journal Entry
Telescope Sees Biggest Cosmic Blast (April 14, 2008)
Swift telescope view of a massive gamma ray burst is on the left. The burst could also be seen without a telescope (right). NASA.
NASA's Swift telescope snapped a picture of the biggest cosmic explosion ever seen. The monstrous blast was 7.5 billion light-years away, halfway across the visible universe. A light-year is the distance light travels in one year, or about six trillion miles. The explosion was powerful enough to be seen with the naked eye.
The explosion was a gamma ray burst, the most violent kind in the universe. Gamma ray bursts occur when a huge star burns up all of its available fuel. The star's core collapses, forming either a black hole or an neutron star. This releases gamma rays, the most intense variety of electromagnetic radiation.
A gamma ray burst produces a spectacular afterglow, captured in the Swift photo above. Astronomers say the burst honors the memory of the well-loved science fiction writer Arthur C. Clarke. Mr. Clarke, who wrote classics such as 2001: A Space Odyssey, died the same day the burst was detected.
The explosion took place within the constellation Bootes. Before the burst was seen the brightest visible object was galaxy M33, found "only" 2.9 million light-years from Earth.
