Annoyingly, some of the most impactful things in our universe just can’t be directly observed. Ignoring the giant pillars of dark matter and dark energy still leaves us with those same ‘don’t emit light’ black holes. Beyond affecting the evolution of the stars they may evolve with or the evolution of the galaxies they may sit in the heart of, it turns out supermassive black holes can hollow out the cores of galaxy clusters.

Researchers compared images from the Hubble Space Telescope, which shows us where stars and nebulae are located, with data from the Chandra X-ray Observatory, which shows the distribution of hot gas. Much to everyone’s surprise, the X-ray images showed massive cavities to either side of the cluster’s central galaxy and lesser cavities above and below. 

In a new paper in The Astrophysical Journal Letters, researchers led by Francesco Ubertosi describe how this kind of a structure could be blown in the intra-cluster gas by a pair of actively feeding supermassive black holes with perpendicular jets. According to study co-author Myriam Gitti: While we think supermassive black holes can form binary systems, it is extremely rare that both of them are observed in an active phase — in this sense the discovery of two close active black holes inflating cavities in [this cluster] is extraordinary.

Along with the cavities seen in X-rays, additional data from the Very Large Array shows two pairs of jets aligned with the two sets of cavities. If the cavities and jets are from two supermassive black holes, they are the closest pair found so far. But before you go assuming that all these hoofprints indicate two horses are hanging out, there is a zebra we’d like to bring to your attention. It is possible, maybe, that one supermassive black hole could be responsible for this system all by itself if it somehow flipped rapidly. How you rapidly rotate an object many million solar masses in size, well, that’s a problem for theorists. For now, just know that apparently the jets associated with supermassive black holes can blow epic bubbles.

More Information

CXO press release

“The Deepest Chandra View of RBS 797: Evidence for Two Pairs of Equidistant X-ray Cavities,” F. Ubertosi et al., 2021 December 16, The Astrophysical Journal Letters