Astronomers call it the monster. It was the biggest and brightest cosmic explosion ever witnessed. Had it been closer, Earth would have been toast.
Because the blast was 3.7 billion light years away, mankind was spared. But orbiting telescopes got the fireworks show of a lifetime in April.
The only bigger display astronomers know of was the big bang that created the universe, and no one was around to see that.
The blast was a gamma ray burst, an explosion that happens when a massive star dies, collapses into a brand-new black hole, creates a supernova and ejects energetic radiation that is as bright as can be as it travels across the universe at the speed of light.
Nasa telescopes in orbit have been seeing these types of bursts for more than 20 years, spotting one every couple of days. But this one was special. It set records, according to four studies published in the journal Science.