A new study, based on data from ESA's XMM-Newton X-ray observatories and NASA's Chandra, sheds new light on a three million light-year hot gas bridge connecting two clusters of galaxies, whose shape is to be doubled by the powerful activity of a nearby supermassive black hole.
The galaxy clusters are the largest objects in the Universe, held together by gravity. They contain hundreds or thousands of galaxies, large amounts of gas of several million degrees that shine brightly in X-rays and huge reservoirs of invisible dark matter.
The system depicted in these images, called Abell 2384, is located 1.2 billion light years from Earth and comprises a total mass of more than 260 billion times the mass of the Sun. In this case, the two galactic clusters collided and they passed each other, releasing a flood of hot gas from each cluster that formed an unusual bridge between the two objects.
The XMM-Newton and Chandra X-ray visualization is shown in blue, along with radio wave observations made with the GMRT (Giant Metrewave Radio Telescope) in India (shown in red) and optical data from the DSS (Digitized Sky Survey; shown in yellow). The new multi-wavelength view reveals the effects of a jet firing away from a supermassive black hole in the center of a galaxy in one of the clusters.
The jet is so powerful that it is doubling the shape of the gas bridge, which has a mass equivalent to about six billion suns. At the crash site, where the jet is pushing hot gas on the bridge, astronomers found evidence of a shock front, similar to a sonic explosion from a supersonic aircraft, which can keep the gas hot and prevent it from cooling to form new ones. stars.
Objects like Abell 2384 are important for astronomers to understand the growth of galaxy clusters.
Computer simulations indicate that, after such a collision, the galaxy clusters oscillate like a pendulum and pass each other several times before merging to form a larger cluster. Based on these simulations, astronomers think that the two groups in this system will eventually merge.
The study describing this work, led by Viral Parekh, from the South African Radio Astronomy Observatory and the University of Rhodes, in South Africa, was published in Monthly Notices of the Royal Astronomical Society in January.