Lewis Andrews

‘Cosmic Snipers’ visualises the most explosions, second only to the big bang in the cosmos: Gamma-Ray Bursts. Gamma-Ray Bursts (GRB) are titanic explosions caused when the most massive stars in the cosmos end their lives in supernovae and birth baby black holes at their cores. When this happens, enormous amounts of energy in the form of gamma rays are released into space in the form of two beams tearing through the star’s poles and shooting out into the cosmos. The universe’s equivalent of a Sniper bullet, if you like, as these high-powered jets of energy fire out into the cosmos, outshining the supernova by a factor of a hundred and containing the equivalent energy in a single second that our Sun will produce in its 10 billion-year lifespan.

 

They were first discovered by accident when in 1960’s by US spy satellites trying to detect gamma rays from Soviet nuclear tests. Detections of short bursts of gamma rays from space remained a mystery for 30 years; however, the source of a GRB was detected in a galaxy 6 billion light-years away, and the theories began of their origins within the most violent of star deaths. 

 

If aimed correctly and close enough, a GRB can be an extinction-level event for a planet harbouring life. GRBs could overload Earth’s ozone layer, rendering it useless against the trickle of Gamma Rays coming from the sun whilst simultaneously delivering a lethal dose of Gamma Rays on the planet. This is probably happening all the time in the distant cosmos, with these cosmic sniper bullets washing over entire solar systems and stripping their planets of life. However, there's no need to worry. Earth gets struck by GRBs at least once a day for a few seconds, but they originate so far away in distant galaxies that their energy is of no harm to us.  However, a GRB may be responsible for an early mass extinction here on Earth. 450 million years ago, a GRB may have been the cause of the late Ordovician extinction, which wiped out 85% of marine species. No GRBs have been observed in our galaxy, and there may only be a handful of candidates of stars that could potentially release GRBs. However, we wouldn't know if one was on the way for a strike on Earth until it was too late since they travel at the speed of light. And you would be dead.