A black hole has been spotted belching out a burst of gamma rays after gulping down part of a nearby star, something never seen before. Such violent burps may actually be the most common type of explosive "gamma-ray burst" in the universe.
The event was named GRB 070610 after the date of its discovery by NASA's Swift satellite on 10 June 2007.
At first it looked like another ordinary long gamma-ray burst (GRB) in a distant galaxy. These outbursts are thought to be the death cries of massive stars collapsing to form black holes.
But this GRB seems to have a different provenance altogether. They suspect that the black hole in the system had some kind of a giant hiccup while chowing down on matter stolen from its companion star. This gamma-ray hiccup behaviour has never been seen before and scientists are not sure how to explain it. But though the burst was much less powerful than typical long GRBs, such events are still quite violent. A similar system called V4641 Sgr set the record for spewing matter out at the highest speed ever observed in our galaxy during a similar outburst, observed in X-rays, in 1999.
It's clearly an unusual event. There's yet another way that nature found to make GRBs, which is very interesting. Low energy
"The reason we haven't seen something like this before is not because it's rare but because it's a low-energy event," Kasliwal says, explaining that this burst is intrinsically about 100 trillion times less powerful than previously observed long GRBs. Those more powerful long GRBs have only been observed in other galaxies and are thought to occur in our own galaxy less than once every 100,000 years
The event was named GRB 070610 after the date of its discovery by NASA's Swift satellite on 10 June 2007.
At first it looked like another ordinary long gamma-ray burst (GRB) in a distant galaxy. These outbursts are thought to be the death cries of massive stars collapsing to form black holes.
But this GRB seems to have a different provenance altogether. They suspect that the black hole in the system had some kind of a giant hiccup while chowing down on matter stolen from its companion star. This gamma-ray hiccup behaviour has never been seen before and scientists are not sure how to explain it. But though the burst was much less powerful than typical long GRBs, such events are still quite violent. A similar system called V4641 Sgr set the record for spewing matter out at the highest speed ever observed in our galaxy during a similar outburst, observed in X-rays, in 1999.
It's clearly an unusual event. There's yet another way that nature found to make GRBs, which is very interesting. Low energy
"The reason we haven't seen something like this before is not because it's rare but because it's a low-energy event," Kasliwal says, explaining that this burst is intrinsically about 100 trillion times less powerful than previously observed long GRBs. Those more powerful long GRBs have only been observed in other galaxies and are thought to occur in our own galaxy less than once every 100,000 years
1 comment:
This is an important information, it will help in better understanding of the mysterious black holes....
--Ashutosh
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