Astronomers have discovered a massive cloud of energetic particles surrounding a galaxy cluster so distant that its light took 10 billion years to reach Earth, offering an unprecedented glimpse into the early universe. The “mini halo” doubles the distance record for such structures and suggests that powerful cosmic forces were shaping the cosmos earlier than scientists previously thought.
The discovery was made using Europe’s Low Frequency Array (LOFAR) radio telescope network, which detected a faint but widespread radio signal stretching over a million light-years. The team found that this signal is not coming from individual galaxies, but rather from the energetic particles filling the space between them.
“This is like discovering a vast cosmic ocean, where entire galaxy clusters are constantly immersed in high-energy particles,” said Julie Hlavacek-Larrondo of Université de Montréal. “It’s astonishing to find such a strong radio signal at this distance, which means these energetic particles and the processes creating them have been shaping galaxy clusters for nearly the entire history of the universe.”
The team analyzed data from LOFAR’s network of over 100,000 small antennas spanning eight European countries. The radio power measured matches patterns seen in nearby mini halos, suggesting similar processes have operated throughout cosmic history.
Two competing theories explain how these energetic particle clouds are formed: supermassive black holes ejecting high-energy particle streams into space or cosmic particle collisions within the cluster’s hot plasma. The discovery challenges current models of how these particles maintain their energy over vast distances and timescales.
This finding has significant implications for our understanding of cosmic evolution, suggesting that both black holes and high-energy particle physics have been energizing galaxy clusters much earlier than expected. Future telescopes like the Square Kilometer Array will detect even fainter signals, potentially revealing more about how magnetic fields and cosmic rays shaped the universe’s earliest structures.
The technical achievement required sophisticated analysis to distinguish the diffuse emission from other sources, but the team is optimistic that this discovery gives us a new window into how galaxy clusters grow and evolve. As Hlavacek-Larrondo noted, “We are just scratching the surface of how energetic the early Universe really was.”
Source: https://scienceblog.com/ancient-galaxy-cluster-reveals-cosmic-energy-from-universes-youth