What can heat distribution within galaxy clusters, which often consist of hundreds to thousands of galaxies, teach astronomers about their formation and evolution? This is what a recent study published in Nature hopes to address as a team of approximately 100 researchers from the XRISM (X-Ray Imaging and Spectroscopy Mission) science team investigated the behavior of gas within galaxy clusters and to better understand how it influences the evolution of galaxy clusters.
For the study, the researchers used the XRISM satellite to observe the Centaurus galaxy cluster, which is located approximately 170 million light-years from Earth. For context, the Andromeda Galaxy, which is the closest galaxy to our own, is located approximately 2.5 million light-years from Earth. in the end, the researchers found that hot gas travels to the central galaxy within the cluster at speeds between 130 kilometers per second and 310 kilometers per second (80 miles per second and 193 miles per second), which they refer to as “gas sloshing” after analyzing computer models to better understand their data.
“We found little turbulence of the high-temperature gas in the galaxy cluster,” said Dr. Kazuhiro Nakazawa, who is a professor in the Department of Physics at Nagoya University and a co-author on the study. “The mechanism, which stops the cooling of the hot gas of this cluster, is a general ‘stirring’ of the hot gas that supplies energy to the center from outside regions, thus maintaining the high temperature.”
Along with their hundreds to thousands of galaxies and hot gas, galaxy clusters are also hypothesized to contain large amounts of dark matter, which is a mysterious gravitational substance that scientists refer to as the “glue” of the universe. In this context, scientists hypothesize that dark matter is responsible for pulling the galaxies together and keeping them together, as well. Overall, galaxy clusters can help scientists better understand the formation and evolution of the early universe.
What new discoveries about galaxy clusters will researchers make in the coming years and decades? Only time will tell, and this is why we science!
As always, keep doing science & keep looking up!
Sources: Nature, EurekAlert!
Featured Image: Hubble mage of the galaxy cluster, Abell 3827. (Credit: ESA/Hubble & NASA, R. Massey)
