Astronomers have identified 44 individual stars in a galaxy nearly 6.5 billion light-years away, marking a breakthrough in the study of distant celestial objects.
This discovery, made using NASA's James Webb Space Telescope (JWST), represents the largest number of stars ever resolved at such a distance. These stars are part of the Dragon Arc, a galaxy distorted by gravitational lensing, a phenomenon where a massive object bends light from a more distant source, magnifying and stretching its image.
The light from the Dragon Arc galaxy is stretched across the sky by the Abell 370 galaxy cluster, creating a long, stretched image that resembles a cosmic dragon.
The 44 stars, discovered by a team led by astrophysicist Fengwu Sun from the University of Arizona, were previously impossible to detect. They were observed through JWST's powerful infrared capabilities, which are crucial for spotting stars that are cooler and dimmer than those seen with older telescopes like Hubble.
Many of the stars in the Dragon Arc are red supergiants, nearing the end of their life cycles and expanding into large, cooler forms. This discovery provides valuable insight into the types of stars that exist in distant galaxies, especially those not typically visible to other telescopes.
Prior to this achievement, detecting individual stars in galaxies billions of light-years away was considered nearly impossible. Previous studies with the Hubble Space Telescope had only identified a handful of stars. However, JWST's sensitivity allowed scientists to see 44 stars, an unprecedented number in such a distant galaxy.
This finding offers a new way to study the evolution of galaxies in the early universe and presents new opportunities to explore dark matter. The research also examined how the cluster's dark matter affects the lensing process, contributing to our understanding of the mysterious nature of dark matter, which influences the movement of galaxies and light.
Published in Nature Astronomy, this discovery is among the most significant in recent years, demonstrating that JWST can provide a clearer, more detailed view of the distant universe.