Mega-Star Blast Is Cosmic Record Breaker

Mega-Star Blast Is Cosmic Record Breaker. Astronomers have finally seen the light from a star which exploded 13 billion years ago in the cosmic dark ages.

Two separate teams traced a gamma-ray burst, the most violent explosions known to exist, from the mega-star which blew up 630 million years after the Big Bang, a report in the journal Nature said.


Exploding star GRB 090423 taken by Nasa's Swift telescope Pic: Nasa/Swift/Stefan Immler

Nasa's telescope captured light from the explosion

Scientists were particularly excited about the discovery because it opens a window on a little-known period of time where the universe was in its infancy.

The gamma-ray burst, called GRB 090423, flashed and crashed towards the end of these dark ages, making it the oldest object ever seen.

"This observation allows us to begin exploring the last blank space on our map of the universe," said Professor Nial Tanvir of the University of Leicester, the lead author of one of the studies.

Co-author Professor Andrew Levan, from the University of Warwick, added: "It is tremendously exciting to be looking back in time to an era when the first stars were just switching on."

The team chased up the rare burst after receiving an alert from Nasa's Swift telescope which spotted it in April this year.

Using two telescopes in Hawaii, they tracked the explosion from about 20 minutes after it was first seen. They also followed its afterglow via a telescope in Chile.

Meanwhile, a team of Italian astronomers led by Ruben Salvaterra used their telescope in the Canary Islands to watch the same burst.

"We knew by our models that these kinds of objects should exist," he said. "Being one of the people that actually detected it is quite amazing."

The astronomers measured the explosion's redshift - the distortion of light as it travelled across space and time - and found it was the highest ever recorded.

The previous oldest object is at least 150 million years younger than the newly discovered gamma-ray burst. ( sky.com )






No comments:

Post a Comment