Astronomers have spotted the most distant star ever observed that is 9 billion light-years from Earth, a new study reported Monday.
“For the first time ever we’re seeing an individual normal star — not a supernova, not a gamma-ray burst, but a single, stable star — at a distance of 9 billion light-years,” said Alex Filippenko, an astronomer at the University of California-Berkeley and co-author of the study.
The star is nicknamed Icarus, after the Greek mythological character who flew too near the sun on wings of feathers and wax that melted. (The formal name is MACS J1149 Lensed Star 1.)
Normally the star would be too faint to view, even with the world’s biggest and most powerful telescopes. But through a quirk of nature that tremendously amplifies the star’s feeble glow, astronomers using NASA’s Hubble Space Telescope were able to pinpoint this faraway star and set a new distance record.
"This star is at least 100 times farther away than the next individual star we can study, except for supernova explosions,” said the study's lead author, Patrick Kelly of the University of Minnesota.
The method that allowed the star to be spotted is called gravitational lensing, which is the bending of light by massive galaxy clusters in the line of sight. The phenomenon can magnify the distant universe and make visible certain objects that are dim and far away.
The detection of the star through the Hubble telescope was possible only because the light from the star was magnified 2,000 times.
The observed light from the newly discovered star was emitted when the universe was only about 30% of its current age — about 4.4 billion years after the Big Bang.
Astronomers say the imminent arrival of new, more powerful telescopes like the James Webb Space Telescope will make it possible to study the evolution of the earliest stars in greater detail than ever expected.
The study appeared in Nature Astronomy, a peer-reviewed British journal.