Recently scientists made a discovery that has forced them to re-think their theories on gamma ray bursts – the most powerful explosions in the cosmos.
Gamma ray bursts signal the birth of black holes. Scientists thought they had figured the nature of gamma ray bursts a year ago, and had classified the bursts into two categories: long or short. The long bursts are those that last more than two seconds. It is believed that they are ejected by massive stars at the furthest edge of the universe as they collapse to form black holes. Short bursts persist for less than two seconds, with some only lasting a few milliseconds. The cause is thought to be the merger of two neutron stars – or a neutron star and a black hole – to form a new or bigger black hole. This newly discovered hybrid gamma ray burst has properties of both known classes but also possesses features that remain unexplained.
Gamma ray bursts signal the birth of black holes. Scientists thought they had figured the nature of gamma ray bursts a year ago, and had classified the bursts into two categories: long or short. The long bursts are those that last more than two seconds. It is believed that they are ejected by massive stars at the furthest edge of the universe as they collapse to form black holes. Short bursts persist for less than two seconds, with some only lasting a few milliseconds. The cause is thought to be the merger of two neutron stars – or a neutron star and a black hole – to form a new or bigger black hole. This newly discovered hybrid gamma ray burst has properties of both known classes but also possesses features that remain unexplained.
X-ray image of the gamma-ray burst GRB 060614 taken by the XRT instrument on Swift. The burst glowed in X-ray light for more than a week following the gamma-ray burst. This so-called "afterglow" gave an accurate position of the burst on the sky and enabled the deep optical observations made by ground-based observatories and the Hubble Space Telescope. Credit: NASA/Swift Team
This hybrid burst came from the constellation Indus, which is 1.6 billion light years away. The evidence suggests that the black hole birth happened in a very different way than from other known bursts. The hybrid lasted for 102 seconds, making it a long burst, but long bursts are normally associated with a supernova (star explosion). This one, labeled GRB 060614 had no associated supernova. It is in fact, in a galaxy with very few stars that could produce either a supernova or a long burst.
This information is based on a press release form NASA, for more information follow this link to the press release.
This hybrid burst came from the constellation Indus, which is 1.6 billion light years away. The evidence suggests that the black hole birth happened in a very different way than from other known bursts. The hybrid lasted for 102 seconds, making it a long burst, but long bursts are normally associated with a supernova (star explosion). This one, labeled GRB 060614 had no associated supernova. It is in fact, in a galaxy with very few stars that could produce either a supernova or a long burst.
This information is based on a press release form NASA, for more information follow this link to the press release.
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