Contrails from ancient galaxies discovered

The "arms" could be traces of superheated gas after the merging of smaller galaxy clusters with the coma cluster, report the researchers in the journal "science. They could be about 300 million years old and hundreds of thousands of light years long.

The team around jeremy sanders of the max planck institute for extraterrestrial physics in garching had discovered the tracks with the rontgen satellites "chandra" and "XMM-newton. Researchers believe that several small galaxy clusters once collided with the massive coma cluster, which consists of thousands of galaxies, emitting a lot of gas in the process. "Similar to the way a jet draws a condensation trail of water vapor behind it as it flies across the sky," according to a statement from the institute.

The researchers were surprised to find that the arms are relatively smooth. According to models, strong turbulence is to be expected when galaxies merge, the researchers explain. The smooth shape, however, points to a "rather quiet backdrop" for the heibe gas in the coma pile, even after many mergers.