Clues About Black Hole Formation Provided By A Stellar Explosion On The Outer Reaches Of The Univers
Clues About Black Hole Formation Provided By A Stellar Explosion On The Outer Reaches Of The Universe
May 8, 2014
University of the Basque Country
A partnership of the UPV/EHU-University of the Basque Country, Ikerbasque and the CSIC-Spanish National Research Council is participating in the detecting, for the first time, of circular light coming from a recently created black hole
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Image Caption: Top left box (a): Image of the field of the GRB121024A captured by the Very Large Telescope (VLT),
Chile. The GRB121024A is the point marked by the dotted lines. The glow of the GRB121024A in the image does not
correspond to its distance from the Earth. In fact, as can be seen, the GRB121024A is one of the brightest objects in the
field, despite being one of the most distant, if not the most distant one, in the image. So the point marked corresponds to
the explosion of a star about ~11,000 million years ago when the age of the Universe was only one third of what it is now.
General box (b): Artist's impression of the GRB121024A. It is possible to see the jets emerging from the dying star in the
centre of which a black hole would form. The blue wave spread by the jet represents the circular polarization detected.
Credit: NASA, Goddard Space Flight Center/S. Wiessinger. [/font]
On 24 October 2012 observatories across the world were alerted about a huge stellar explosion, the GRB121024A, which had been located just hours before in the Eridanus constellation by NASA’s Swift satellite. However, only the European Southern Observatory using its Very Large Telescope (VLT) located in the Atacama desert in Chile managed to take accurate polarimetric measurements of the phenomenon. The data obtained on that explosion, which took place about 11,000 million years ago, have made it possible to reconstruct how a black hole is formed. The work, which has had the participation of the Ikerbasque researcher Javier Gorosabal, co-director of the Associated Unit with the Institute of Astrophysics of Andalusia/CSIC-UPV/EHU, has been published in the prestigious journal Nature.
There is no other event in the cosmos that can compete in terms of energy and intensity with stellar explosions on the outer reaches of the universe and which are known as LGRBs (Long Gamma-Ray Bursts): in just one second a single GRB can emit as many as hundreds of stars like the Sun during its 10,000-million-year-lifetime.
For the last decade astrophysicists have been in possession of strong evidence that LGRBs occur when the so-called massive stars burst; these are huge stars with masses of up to hundreds of times bigger than that of the Sun and which, moreover, spin rapidly on a rotation axis.
As these stars are massive and spin, they do not explode like a normal star, which does so radially, as a ball does when it deflates, for example. The implosion of these huge stars would produce, according to theoretical models, a huge spinning top, which would turn in the way that water rotates down the plughole of a basin, until a black hole is finally formed. The energy given off by this gigantic explosion would be emitted in two jets displaying a high level of energy and which would be aligned with the rotation axis of the dying star.
More:
http://www.redorbit.com/news/space/1113141808/clues-about-black-hole-formation-provided-by-stellar-explosion-on-outer-reaches-of-the-universe-050814/#r0bYmM0swsLiOKIm.99
