Hubble was one of four great observatories launched in the last century. These flagship missions included the Compton Gamma-ray Observatory, which retired in 2000 and has since been supplanted by the Fermi Gamma-ray Telescope. Spitzer was also part of this program, as was the Chandra X-ray Observatory. Planned to fly for five years, this mission is still going strong and returning amazing science.

In a new image, Chandra has revealed what looks like a small jellyfish in a bubble of space. In reality, the giant bubble Chandra sees is a massive galaxy cluster that is consuming a smaller cluster plunging toward its core. The light we’re seeing comes from the hot intracluster gas, and the structures show us where materials of different temperatures and densities are located. The features that look like jellyfish arms are actually tails of hot gas pulled out of the smaller cluster. 

Chandra rarely works alone, and in this research, Chandra data have been combined with optical images that show galaxy locations from PanSTARRS and radio data from LOFAR highlights which of the galaxies have actively feeding central black holes. Together, this data allows researchers, and us, to see how gas interacts and galaxies get disrupted during mergers and reminds us that an old observatory can still do amazing science.

More Information

Chandra press release

“Nonthermal phenomena in the center of Abell 1775: An 800 kpc head-tail, revived fossil plasma and slingshot radio halo,” A. Botteon et al., 2021 May 11, Astronomy & Astrophysics

“The Merger Dynamics of the Galaxy Cluster Abell 1775: New Insights from Chandra and XMM-Newton for a Cluster Simultaneously Hosting a WAT and a NAT Radio Sources,” Dan Hu et al., to be published in The Astrophysical Journal (preprint on arxiv.org)