So, the star's gravitational lens had a multiplying effect. "In May of 2016, however, a star in the MACS J1149+2223 galaxy cluster also temporarily became aligned," and it had the effect of boosting the magnification of Icarus to 2,000 times, Kelly told Live Science. Usually, the cluster magnifies Icarus by a factor of about 600. Another "lens" - this time, a sun-size star - had passed directly between Icarus and the Hubble Space Telescope's trained eye. (MACS J1149+2223 is located 5 billion light-years from Earth.)Īnd they were right. He was focusing on the supernova called SN Refsdal when he noticed the bright light and suspected this object was even more highly magnified than the supernova in that cluster. Kelly, who was the lead author on a new study describing the findings, spotted the faraway star Icarus while looking at Hubble Space Telescope images of a supernova (one he discovered in 2014) that had been shot through a gravitational lens - in this case, a galactic cluster called MACS J1149+2223 - in the constellation Leo. Vinicius Placco of the National Science Foundation's NOIRlab in Tucson, Arizona, - who was not involved in the study - described the findings as "amazing work".ĭr Placco said that, based on the Hubble data, Earendel may well have been among the first generation of stars born after the Big Bang.įuture observations by the newly launched James Webb Space Telescope should provide more details, he said, and "provide us with another piece of this cosmic puzzle that is the evolution of our universe".A massive cluster of galaxies (left) magnified a distant star more than 2,000 times, making it visible from Earth (lower right) even though it is 9 billion light-years away. "It's such a gift really from the universe." "Usually, they're all smooshed together … But here, nature has given us this one star - highly, highly magnified, magnified by factors of thousands - so that we can study it," said NASA astrophysicist Jane Rigby, who took part in the study. While Hubble has spied galaxies as far away as 300 million to 400 million years of the universe-forming Big Bang, their individual stars have been impossible to pick out. Loading YouTube content 'A gift from the universe' If not for that, Icarus and Earendel would not have been discernible, given their vast distances. Gravity from clusters of galaxies closer to us - in the foreground - serve as a lens to magnify smaller objects in the background. In both instances, astronomers used a technique known as gravitational lensing to magnify the minuscule starlight. That's more than 4 billion years after the Big Bang. The previous record-holder, Icarus, also a blue supergiant star detected by Hubble, formed 9.4 billion years ago. He nicknamed the star Earendel - an Old English name that means "morning star or rising light" - "a fitting name for a star that we have observed in a time often referred to as 'Cosmic Dawn'". "We're seeing the star as it was about 12.8 billion years ago, which puts it about 900 million years after the Big Bang," said astronomer Brian Welch, a doctoral student at Johns Hopkins University and lead author of the study in the journal Nature. It takes eons for light emitted from distant stars to reach us. Its swift demise makes it all-the-more incredible that an international team detected it with observations by the Hubble Space Telescope. However, this luminous, blue star is long gone, so massive that it almost certainly exploded into bits just a few million years after emerging.
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