PCS 581 Lecture Notes - Lecture 13: White Dwarf, Ordovician, Smog
Document Summary
Discovery: early (cid:883)96(cid:882)"s; the us launches satellites to detect nuclear bomb tests, on earth or on, looking for nuclear gamma ray flashes that last a millionth of a second, found gamma ray luminosity the moon. Detecting gamma rays: are the highest energy photons, pack a wallop, do not reflect off of mirrors or glass, just punch through it. Compton results: bursts detected once a day on average, based on this distribution they are coming from the solar system. Grb discovered march 2008: visible to the naked eye, from 7. 5 billion light years away the brightest thing ever seen. The brightest things: highest total luminosity of anything in the universe. If the light is going out in all directions it would be more than a million times the milky way. If they are shooting out in tightly focused beams like pulsar, we should see all of them.
