The James Webb Space Telescope (JWST) has made a ground-breaking discovery: it has taken pictures of the second and fourth-most distant galaxies ever spotted. This exceptional discovery in the Pandora’s Cluster, also known as Abell 2744, was made by a group of scientists from throughout the world under the direction of Penn State researchers. They have detected two galaxies, UNCOVER z-13 and UNCOVER z-12, located about 33 billion light years from Earth, using spectroscopic data from the cutting edge observatory.
Their discoveries, which were published in the Astrophysical Journal Letters, provide fresh insight into the early universe and a rare look at a period when the universe was only 330 million years old. These galaxies stand out because of their size and shape—they are best compared to a peanut and a fluffy ball. The biggest of the two, UNCOVER z-13, is about 2,000 light-years across, making it nearly six times larger than previously known galaxies at similar distances—a significant size for a galaxy from the early universe.
The study’s first author, Bingjie Wang, underlined the importance of these far-off galaxies in enhancing our comprehension of the early cosmos. “Very little is known about the early universe, and the only way to learn about that time and to test our theories of early galaxy formation and growth is with these very distant galaxies,” Wang said. After traveling 13.4 billion light years to reach the JWST, the light from these ancient galaxies provides important new understandings of the unusual physics governing galaxies close to the cosmic birth.
What makes these galaxies particularly intriguing is their diversity, challenging prior assumptions about the uniformity of early galaxy properties. The two discoveries are especially noteworthy as they were found in one of Webb’s first deep-field images, taken shortly after the telescope commenced scientific operations in 2022. The region, strategically chosen behind several galaxy clusters, utilizes gravitational lensing to allow scientists to peer further into the cosmos, revealing the universe’s appearance shortly after the Big Bang.
Because of the JWST’s unparalleled capacity to look farther into the distant past, science is reevaluating early cosmic evolution models in light of this revolutionary shift in our understanding of the universe. The telescope has the potential to unearth more mysteries buried in the great reaches of space as it continues its mission.