![]() And that’s what you expect from gravitational lensing,” study leader Patrick Kelly of the University of Minnesota, Twin Cities says in a press release. “The source isn’t getting hotter it’s not exploding. According to a model outlined this week in Nature Astronomy, Icarus was magnified when a star in that galaxy cluster moved in front of the more distant star, boosting it to 2,000 times its actual brightness. This is when gravity from a massive celestial object acts like a magnifying glass, bending and amplifying the light from objects behind it.įive billion light-years from Earth, a galaxy cluster sits between our planet and Icarus. Its glow was given a boost thanks to what's called gravitational lensing. How Was It Seen?Ī group of astronomers had been monitoring a far-off supernova-the explosive death of a giant star-using the Hubble Space Telescope when they saw a new speck of light. Despite its brilliance, it still took nine billion years for its shining light to reach Earth. It's much bigger than our own sun and hundreds of thousands of times brighter. The supergiant star (officially named MACS J1149+2223 Lensed Star 1) lives more than halfway across the observable universe. In addition, in 2020 NASA will launch Hubble’s successor, the James Webb Space Telescope, a more powerful observatory that will find other distant stars like this one.A bright blue giant nicknamed Icarus is now the farthest star humans have ever seen. Kelly said they’ll use the information to understand Icarus and gain a rare and detailed look into its evolution. “As more objects move in front of (Icarus), we will be able to take a census of everything in the cluster.” Since the light from Icarus is 9 billion years old, Kelly said the star by now has likely been dead for billions of years. Hubble telescope breaks record, measures most distant galaxy ever seen Without gravitational lensing, the star would’ve been impossible to see, even with a powerful telescope, he said. “Being able to see one star at a time is helpful,” Kelly said. The cluster of galaxies act as a natural lens in space, bending and amplifying light while illuminating Icarus. The mass in this case was a galaxy cluster about 5 billion light years from Earth, between our planet and Icarus. Simply put, gravitational lensing is the concept that mass bends light. The light turned out to be an individual star that only became visible with the help of gravitational lensing. There are 10 times more galaxies in our universe than we'd estimated Two years later, they were observing the cluster when they noticed a new point of light had appeared. Observers are seeing the star as it looked when the universe was about 30% of its current age.ĭiscovery of the star began in 2014 when astronomers were using Hubble to study a galaxy cluster. The Icarus visible to us now is a very young star, Kelly said. Kelly said its nickname stuck because the star will appear to grow brighter and then eventually disappear like Icarus’ waxed and feathered wings, which fell off when he got too close to the sun. “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.”Īccording to a report published by the Space Telescope Science Institute, which operates the Hubble, the star is so far away its light has taken 9 billion years to reach Earth. “This is the first time we’re seeing a magnified, individual star,” Kelly said in a statement. The inset panels at right show the view in 2011, before Icarus was visible, compared with the star's brightening in 2016. Icarus is only visible because it is being magnified by the gravity of a massive galaxy cluster.
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