The James Webb Space Telescope (JWST) has achieved a groundbreaking feat by capturing images of 44 individual stars in a galaxy situated halfway across the observable universe. This discovery was made possible by a rare cosmic arrangement, allowing scientists to identify these stars in a region previously thought impossible to observe at such detail.
The newly identified group of stars, located within a remote galaxy, presents a fascinating opportunity for astronomers to explore the behavior of dark matter. Rogier Windhorst, an astronomer from Arizona State University, expressed surprise and excitement about the findings, noting the unexpected number of stars visible in the data. He remarked, “I never dreamed of Webb seeing them in such large numbers. And now here we are observing these stars popping in and out of the images taken only a year apart, like fireflies in the night.”
The distant galaxy, home to these 44 stars, is commonly referred to as the “Dragon.” Its light began its journey across the universe approximately 6.5 billion years ago, during a time when the universe was half its current age. The red supergiants discovered within this galaxy are in the final stages of their lifecycle, much like Betelgeuse, a well-known star poised to explode in the constellation Orion.
The galaxy cluster Abell 370, situated around 4 billion light-years from Earth, features arcs of light, known as the “Dragon Arc.” These are caused by gravitational lensing, a phenomenon where light from distant galaxies is bent around massive objects, such as galaxy clusters, creating distorted images. This natural magnification process has allowed astronomers to study these faraway celestial bodies with unparalleled clarity using telescopes like the JWST.
The “Dragon” is actually a composite of several images of a single spiral galaxy, resulting from its alignment with the Abell 370 cluster. This cluster itself comprises hundreds of galaxies tightly bound by gravity, located in the constellation Cetus. Abell 370 acts as a cosmic lens, magnifying and warping light from galaxies positioned behind it, rendering them visible to powerful observation tools.
Fengwu Sun, a postdoctoral researcher, made the initial discovery while examining gravitational lensing in images from 2022 and 2023. Sun explained that upon processing the data, numerous individual stars became apparent, marking a record-breaking observation for such a distant region. Sun’s findings underscore the significance of the JWST’s capabilities in furthering our understanding of the universe.
The alignment of stars within Abell 370 and those in the background galaxy further amplified their brightness, allowing for their identification. This chance occurrence, combined with variations in the gravitational lensing landscape, caused the stars’ visibility to flicker like lights on a Christmas tree, according to Nicholas Foo, a co-author of the study.
The James Webb Space Telescope continues to astonish and expand the frontiers of astronomical research with its remarkable ability to uncover distant celestial phenomena. This groundbreaking discovery not only highlights the telescope’s advanced technological capabilities but also opens new avenues for studying the universe’s most elusive components, such as dark matter.
Source: Space
