The dynamic nature of our universe appears in different ways in different objects. If you look at a massive galaxy cluster in optical light, you can often find evidence of trauma: gas and dust torn from their systems and galaxies deformed through close encounters with their neighbors. The true drama, however, pops out in radio light, where the trails of particles and tangled magnetic fields appear to shine. 

In a new data set on the cluster Abell 2255, a team led by Andrea Botteon captures all these effects in stunning detail using the LOFAR radio telescope. According to team member Gianfranco Brunetti: The filaments discovered by LOFAR could form exactly as a consequence of these turbulent motions. Another possibility that we are considering is that the filaments originate from the interaction between the galaxies, which move at speeds of many hundreds of km/s inside the cluster and the plasma that produces the radio emission of the halo.

The degree of emissions from shockwaves is something that had been somewhat anticipated, but this is the first study to look at how far the radio emissions extend from this cluster. According to team member Reinout van Weeren: One of the goals is to understand if the radio emission extends also beyond Abell 2255, tracing the gigantic cosmic web that connects clusters of galaxies in the Universe.

More Information

European Astronomical Society press release 

“The Beautiful Mess in Abell 2255,” A. Botteon et al., 2020, to appear in the Astrophysical Journal (Preprint on arxiv.org)