Scientists have spotted the oldest and most distant single star ever recorded, thanks to the Hubble Space Telescope and a serendipitous alignment of several galaxies. The star existed nearly a billion years after the Big Bang, according to the team of scientists, who published their findings in Nature on Wednesday.
Under usual circumstances, our strongest telescopes can only spot individual stars in our closest galactic neighbors. But in a phenomenon called “gravitational lensing,” a cluster of galaxies known as WHL0137-08 lined up in a way that created “a powerful natural magnifying glass,” NASA wrote on its website, allowing the Hubble Space Telescope to spot the distant star.
NASA/ESA/Brian Welch (JHU)/Dan Coe (STScI)/Alyssa Pagan (STScI).
The scientists named the star Earendel, meaning “morning star” or “rising light” in Old English. The star may be up to 50 times the mass of our sun and millions of times as bright, and because of its distance from Earth, it took 12.9 billion years for its light to reach us, NASA said.
Victoria Strait, postdoc at the Cosmic Dawn Center, Copenhagen, and a collaborator and co-author of the study, said that the old star offers scientists an opportunity to learn more about the past.
“As we peer into the cosmos, we also look back in time, so these extreme high-resolution observations allow us to understand the building blocks of some of the very first galaxies,” she wrote in a press release.
The previous oldest and most distant single star was observed by Hubble in 2018. The light from that star, named Icarus, took 9 billion years to reach Earth, according to NASA.
The research team hopes to prove Earendel is a single star, and not a cluster of stars, not just with computational models — which all point towards the light source being a single star — but also with the newly-launched James Webb telescope.
“Webb will even allow us to measure its chemical composition. Potentially, Earendel could be the first known example of the Universe’s earliest generation of stars,” Sune Toft, leader of the Cosmic Dawn Center, professor at the Niels Bohr Institute and member of the research team, wrote in the press release.
