Latest news with #AnthonyEnglert
News18
5 days ago
- Science
- News18
700 Million Light-Years Away, One Galaxy Steals Stars From Another, Forming A Bridge
Last Updated: Scientists say Abell 3667 formed from two smaller clusters colliding a billion years ago, with each cluster's central galaxy and satellites now converging Astronomers have been astounded by a remarkable event unfolding in space. Approximately 700 million light-years from Earth, two enormous galaxies are being drawn together by mutual gravitational forces. For the first time in a cluster so proximate, scientists have observed stars being pulled from one galaxy towards the other. This phenomenon has been witnessed in the galaxy cluster Abell 3667, where a faint but extensive stream of stars, stretching roughly 1 million light-years, is forming. This stellar bridge is linking the cluster's two brightest galaxies. According to scientists, the grand union of two clusters, Abell 3667, results from the collision of two smaller clusters that began merging about a billion years ago. Each cluster had its own dominant central galaxy, and now these giants, along with their satellite galaxies, are converging. The formation of the star bridge during this time is a testament to their long history and the strength of the gravity in the region. Anthony Englert, a PhD researcher at Brown University, remarked, 'This is the first time such a structure has been seen on such a large scale and in such a close cluster. This was a big surprise for us." The bridge, made of intra-cluster light (ICL), comprises light from stars that have been stripped from their original galaxies and are floating in space. Observing such faint light was challenging, requiring scientists to combine data accumulated over several years from the Dark Energy Camera at Cerro Tololo Inter-American Observatory in Chile. The final image was created by stacking a total of 28 hours of data. Englert noted, 'It was just a coincidence that many astronomers took pictures of Abell 3667 over the years and we saw this view by combining them all." Galaxies At Both Ends Of The Bridge At the upper end of the bridge lies IC 4965, a lenticular (disk-like) galaxy with several smaller galaxies nearby that are joining the cluster. At the lower end is JO171, known as the 'Jellyfish Galaxy', which has long streams of gas being pulled from one side. As JO171 merges with Abell 3667, its gas reserves are being depleted, halting star formation in some regions. Clue To The Mystery Of Dark Matter This bridge of stars is not only visually stunning but also scientifically significant. Researchers believe that intra-cluster light can map the distribution of dark matter, which constitutes 80% of the universe's mass but remains invisible. Co-author Ion Dell'Antonio explained, 'The distribution of this light mimics the distribution of dark matter. It gives us a chance to 'see' dark matter." This discovery is just the beginning. Starting next year, the Vera C. Rubin Observatory will commence its Legacy Survey of Space and Time (LSST), creating an extraordinary map of the southern sky over ten years. Using the world's largest digital camera, it will unveil new stories of thousands of galaxy clusters. view comments Disclaimer: Comments reflect users' views, not News18's. Please keep discussions respectful and constructive. Abusive, defamatory, or illegal comments will be removed. News18 may disable any comment at its discretion. By posting, you agree to our Terms of Use and Privacy Policy.
Gizmodo
05-08-2025
- Science
- Gizmodo
Deepest-Ever Field Image of Giant Galaxy Cluster Is a Brutal Reminder of Your Cosmic Insignificance
When it comes to deep space observations, our cosmological insignificance seems to grow with the resolution of our telescopes' cameras. In the latest advance, astronomers constructed the deepest-ever images of Abell 3667, a massive galaxy cluster located 700 million light-years from Earth—and most of the tiny dots you see represent entire galaxies. But the latest images of Abell 3667 also offer 'whispering evidence of past galactic interactions,' which astronomers document in detail in a paper published today in The Astrophysical Journal Letters. The team, led by astronomers from Brown University, caught Abell 3677 at a particularly lustrous moment in space-time, during a merger of two of the clusters' brightest galaxies. The stellar union, resembling a starry bridge stretching across the cluster, generated powerful gravitational bursts that yanked away the occasional stray star from other galaxies. Together, these lone stars emit a faint glow known as intracluster light (ICL)—and it's this phenomenon that researchers are investigating to explore Abell 3677's past. Specifically, it appears likely that Abell 3667 also formed from the rapid merger of two galaxy clusters, which previous X-ray and radio observations had predicted. This latest observation, however, represents the first ever optical evidence to support this idea. 'This is the first time a feature of this scale and size has been found in a local galaxy cluster,' Anthony Englert, study lead author, said in a statement. 'We knew that it was possible for a bridge like this to form between two galaxies, but it hadn't been documented anywhere before now. It was a huge surprise that we were able to image such a faint feature.' The team had an unusually long observation period for this project, which partly enabled them to construct such a detailed image. In addition to the intracluster light, the researchers captured faint, wispy puffs of cosmic dust called integrated flux nebulae, seen as bluish ribbons of light streaking across the image. 'It was just a happy coincidence that so many people had imaged Abell 3667 over the years, and we were able to stack all of those observations together,' Englert noted. The researchers have some outstanding questions about Abell 3677 and, more importantly, intracluster light. Fortunately, their timing couldn't have been more impeccable; with the Rubin Telescope officially up and running, astronomers are now better equipped to further probe these questions. 'Rubin is going to be able to image ICL in much the same way as we did here, but it's going to do it for every single local galaxy cluster in the southern sky,' Englert said. 'What we did is just a small sliver of what Rubin is going to be able to do. It's really going to blow the study of the ICL wide open.' Essentially, if this new image doesn't make you feel small, you might want to wait for the soon-to-come Rubin versions of this image. In fact, if Englert is right, we'll be seeing multiple versions of this image, and in higher resolution, too. So, for better or worse, we humans will only get smaller from here.
