On April 27, the brightest gamma-ray burst ever witnessed was spotted by several satellites in the direction of the constellation Leo 3.8 billion light-years away
The cosmic explosion, known as GRB 130427A, likely occurred after a star about 20 to 30 times the mass of our sun ran out of fuel and collapsed into a black hole before going supernova and ejecting energetic radiation.
Although Nasa telescopes have been capturing bursts for more than 20 years, this particular was five times greater than its nearest competitor, which was recorded in 1999. Commenting on the titanic gamma-ray burst (GRB), UK astronomer Paul O’Brien from the the University of Leicester, said:
“We normally detect GRBs at great distance, meaning they usually appear quite faint. In this case, the burst happened only a quarter of the way across the universe — meaning it was very bright. On this occasion, a powerful supernova was also produced — something we have not recorded before alongside a powerful GRB — and we will now be seeking to understand this occurrence.”
Fortunately, the massive explosion occurred 3.8 billion light-years distant, which was too far away to threaten the Earth. However, if such a gamma-ray burst was to occur within 1,000 light years of our planet, Earth’s ozone would have been badly damaged and life on the planet would have faced grave danger. A gamma-ray burst, for instance, may have caused the Ordovician extinction which killed 60% of all marine invertebrates 450 million years ago. No need to worry, though, as Scientists have put the chances of a gamma ray burst occurring in our galaxy at less than 1 in 10 million.
“The prediction is that there would be one [gamma-ray burst] close to the Earth to do us harm every 500 million years. At some point in the Earth’s history we probably were irradiated by a gamma-ray burst, and it will happen again at some point in the future… But the chances of it happening in our lifetime are very low,” explained Prof O’Brien.