In a galaxy far, far away, a blue ‘supergiant’ named Icarus becomes farthest star ever seen

A blue “supergiant” nine billion light years away is the most distant single star ever to be observed by astronomers.

Usually at such distances scientists can only image galaxies, collections of billions of stars such as our own Milky Way, or supernovas and gamma ray bursts, colossal cosmic explosions.

Beyond about

100 million light years it is impossible to make out individual stars even with the most powerful telescopes. In this case, a rare cosmic alignment naturally magnified the supergiant more than 2,000 times, allowing astronomers to see it.

The B-type blue supergiant star, hundreds or even thousands of times brighter than the sun, was discovered in Hubble Space Telescope images taken over the course of a year between April 2016 and 2017.

It could only be seen because of an effect called “gravitational lensing” that happens when massive galaxy clusters bend the light of objects behind them.

In effect, the galaxies act as a magnifying glass that can render dim far away objects visible. The lensing phenomenon, predicted by Albert Einstein, is the result of a massive object bending space-time around it and forcing light beams to take a curved path.

Lead scientist Dr Patrick Kelly, who worked on the observations while at the University of California at Berkeley, US, said: “You can see individual galaxies out there, but this star is at least 100 times farther away than the next individual star we can study, except for supernova explosions.”

The star has the long formal name MACS J1149 Lensed Star 1 (LS1), but has been dubbed “Icarus” by the astronomers.