Astronomy: A black hole is born

In May 2005 NASA reported that the Swift spacecraft has detected for the first time the birth of a black hole. Of course we can't see black holes, because light and everything else that enters them is lost to observation. But when a black hole forms, and just before the existing star starts to implode, theorists think that some high-energy process vents some of the stars material back into space. Swift detected a high-energy gamma-ray burst and signaled scientist on Earth, who witnessed a faint flash of light. It is believed that two neutron stars have collided, which caused a black hole to form and Gamma rays in the process. The collision took place on a distance of 2.2 billion light-years from Earth, so it actually took place 2.2 billion years ago. The burst has been named GRB050509b. Gamma ray bursts come from all over the universe and have been witnessed since 1967 when the first burst was detected by accident. Long-duration bursts last a few hundred seconds and are thought to be associated with the formation of black holes when massive stars explode and collapse, although this is not certain. In recent years, scientists have detected X-ray and optical afterglows of these long bursts. Very short-duration bursts, like the one Swift detected, last only a tiny fraction of a second. Until now, no optical afterglows from these bursts have been detected. Theorists think a burst like this represents the formation of a black hole a few times the mass of the Sun, but if so, then there should be flashes of X-rays and visible light too. Each burst is extremely powerfull, it can briefly outshine an entire galaxy. Gamma-ray bursts in our own galaxy are very rare. Some scientists speculate that such bursts in the Milky Way's past might have caused mass extinctions on Earth. Related subjects >> A suspected black hole in the Milky Way Galaxy >> Betelgeuse, a star going supernova >> Supernova SN1987A >> The Compton Gamma Ray Observatory >> Official Swift internetsite

Artist impression of Swift observing the Universe for Gamma explosions. The spectrum of electromagnetic radiation. Visible light is only a small portion of the total spectrum. Gamma rays are the most powerfull rays, one Gamma foton carries millions of more energy compared to a foton of visible light.