Source Pravda.Ru

Astronomers spot most distant star explosion ever

Astronomers using NASA's Swift satellite have detected the most distant explosion ever discovered in the universe, Wednesday, the collapse into a black hole of a massive star about 12.6 billion light-years from Earth.

The event occurred about 1.1 billion years after the big bang, the explosion that created the universe an estimated 13.7 billion years ago, the scientists calculated. The only more distant objects ever detected are a quasar and a single galaxy, both about 12.7 billion light-years away.

"This is what we've all been hoping and waiting for," said University of Chicago astrophysicist Donald Lamb. "This breaks the record for most distant explosion by a huge amount [500 million light-years], and I don't think we'll have to wait long to break it again."

The massive blast, known as a gamma ray burst, lasted 200 seconds and was detected Sept. 4 by the Earth-orbiting Swift, which relayed the sighting to astronomers who used ground-based telescopes to observe the burst and its afterglow. Because the explosion was so distant, light from it is only now reaching Earth, reports Washington Post.

"It was really exciting news for the Swift team when this Swift data were sent to the ground," said Neil Gehrels, the space agency's chief investigator for the Swift spacecraft. "This is exactly what we had built Swift to detect."

The exploding star the Swift satellite observed was typical of the death of a massive star. These blasts are the most powerful in the universe, sending out 100 million times the energy the Sun does in one year. They are not rare, but occur daily, emitting their light in high energy gamma rays. If you could see gamma rays, the sky would twinkle with such bursts.

As soon as Swift detected the explosion, ground telescopes worldwide were trained on the x-ray and visible light afterglow and confirmed the event.

University of North Carolina astronomer Daniel Reichart measured the non-visible, infrared wavelengths of light from the dying star. His calculations show that the explosion occurred almost 13 billion years ago, close to the time of the cataclysmic explosion believed to have created the universe, the Big Bang.

"This cosmic explosion occurred nearly 900 million years after the Big Bang," he said. "That may sound like a long time, but the universe is 13.7 billion years old, which means that this star exploded when the universe was six to seven percent of its current age."

The observance sets a new record for the distance and age of an observed star explosion. The next oldest exploding star ever witnessed took place 500 million years later, informs VOA.