A team of astronomers using the pan-European Low Frequency Array (LOFAR) telescope has made a groundbreaking discovery, spotting a rare mini-halo around the galaxy cluster SpARCS1049. The halo is a sprawling, ghostly glow surrounding the cluster that lies over 10 billion years away, emitting light from when the universe was just 3.8 billion years old.
The team’s excitement stems from the fact that this is the farthest distance mini-halos have been detected so far, with most previous discoveries sitting less than five billion light-years away. The LOFAR data reveal a halo spanning over a million light-years, suggesting that entire galaxy clusters are constantly immersed in high-energy particles.
Experts believe that either supermassive black holes or cosmic ray hadrons could be responsible for pumping energy into the cluster’s intergalactic medium. Determining which process dominates is crucial, as it affects how astronomers model everything from black-hole feedback to X-ray brightness.
The discovery provides a rare window into the physical conditions inside young clusters and allows researchers to infer information about the ages and energies of relativistic particles. The upcoming Square Kilometre Array (SKA) telescope will be able to map distant halo shapes and probe their magnetic fields with unmatched resolution, potentially capturing them as black holes cycle through active and dormant phases.
“This discovery gives us a new window into how galaxy clusters grow and evolve, driven by both black holes and high-energy particle physics,” said co-lead author Julie Hlavacek-Larrondo. “We are just scratching the surface of how energetic the early universe really was.”
Source: https://www.earth.com/news/ancient-radio-signal-just-changed-what-we-know-about-the-early-universe