A massive explosion that was spotted in 2009 has been declared, by some at least, to be the most distant object ever seen. It's ninety-six percent of the way to the visible limit of the universe.
In 2009 astronomers spotted an explosion in the sky. Although it has since been calculated to have the brightness of a million million suns, it was only a smudge. The dimness was reasonable enough, since it had to travel a long way to get to earth. The universe is calculated to be 13.7 billion years old. Since light takes time to travel, the more time light takes to get to earth, the farther away the object is. The explosion is calculated to be 13.14 billion light years away.
Scientists believe that the gamma ray burst, poetically named GRB 090423, was the explosion of an early star. The star was formed, and exploded, when the universe was only 520 million years old, and ten percent of its current size. At the time, it formed some giant stars, and they exploded spectacularly.
Gamma ray bursts are so energetic that they are visible over distances of billions of lightyears. Although they only last for a brief period of time, they have an afterglow that allows scientists to zero in on their position in space. GRB 090423 had a very faint afterglow. Soon afterwards it was only visible in infrared. Since people have no trouble seeing afterglow from nearby cosmic explosions, the lack of it in this case showed that the more minor lights had been filtered out or redshifted. Two years of investigated led scientists to conclude that this explosion was possibly the most distant object ever seen by humans.
Image: Gemini Observatory / AURA / Levan, Tanvir, Cucchiara