It might look like a tiny speck amid a bejewelled vista of the universe, but scientists say a pinprick of light in an image captured by the Hubble space telescope is the most distant individual star ever seen that is not a supernova.
The team behind the find say the light was emitted from the star -- dubbed Icarus but officially named MACS J1149+2223 Lensed Star 1 -- when it was more than 9bn light years from Earth. Icarus is now much further away but will have died, forming either a black hole or a neutron star.
"We are looking back three-quarters of the way almost to the big bang," said Dr Patrick Kelly, first author of the research from the University of Minnesota.
Stars at such distance are normally too faint to be identified individually, unless they explode in a supernova. But it seems a chance alignment of the heavens made Icarus visible.
"It’s more than 100 times farther away than the next most distant individual star we can observe," said Kelly.
Writing in the journal Nature Astronomy, an international team of researchers reveal how their curiosity was piqued in 2016.
The team were studying a supernova known as SN Refsdal in a galaxy more than 9bn light years away when they noticed a pinprick of light that appeared four times brighter than in previous images. This seemed to come from an object in the same galaxy as the supernova, and appeared in the environs of a well-known galaxy cluster that lay just over 5bn light years from Earth.
"As we monitored the cluster due to SN Refsdal, we obtained imaging of the cluster regularly, and we saw the 'Icarus region' brightening up," said Dr Mathilde Jauzac, another author of the study from Durham University.
The speck, the team determined, was down to a star whose brightness had been magnified by a phenomenon known as gravitational lensing whereby light emitted by the star is bent by the gravitational effect of objects in front of it -- in this case the galaxy cluster.
The team were studying a supernova known as SN Refsdal in a galaxy more than 9bn light years away when they noticed a pinprick of light that appeared four times brighter than in previous images. This seemed to come from an object in the same galaxy as the supernova, and appeared in the environs of a well-known galaxy cluster that lay just over 5bn light years from Earth.
"As we monitored the cluster due to SN Refsdal, we obtained imaging of the cluster regularly, and we saw the 'Icarus region' brightening up," said Dr Mathilde Jauzac, another author of the study from Durham University.
The speck, the team determined, was down to a star whose brightness had been magnified by a phenomenon known as gravitational lensing whereby light emitted by the star is bent by the gravitational effect of objects in front of it -- in this case the galaxy cluster.
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