Data from lost Hitomi satellite suggests black holes may be galactic regulators

Earlier this year, the Japan Aerospace Exploration Agency (JAXA) launched its Hitomi satellite into space. The x-ray satellite was intended to study, among other things, the Perseus cluster, a massive cluster of galaxies more than 200 million light years from Earth. Hitomi was the most advanced x-ray satellite to launch successfully into space and had the potential to lead to a number of excellent discoveries, but unfortunately, it was only a month before the satellite started to spin out of control and break apart, with JAXA announcing it had failed in its attempts to reconnect with the satellite not long after.

However, before spinning out of control, Hitomi was able to capture some data on the Perseus cluster and how the supermassive black hole at its center may help or hinder the creation of new stars. Galactic clusters like Perseus are home to a lot of plasma, which is visible when we look at x-ray images of the clusters. This plasma is responsible for the formation of new stars, but the limited findings from Hitomi show that Perseus's supermassive black hole stirs the plasma with giant gas bubbles that are ejected from near its event horizon.

As they move through space, the turbulence that comes with these bubbles rocks the plasma at the cluster's center, heating it up and, in the process, preventing it from getting cool enough to form new stars. In this way, the supermassive black hole at the center of the Perseus cluster becomes something of a galactic regulator, heating up the plasma that's within the cluster to control the rate at which new stars are formed. It's an exciting discovery, and it promises more to reveal once we can manage to get another x-ray satellite back up into space and actually mapping the center of the Perseus cluster.

That a supermassive black hole can discourage star growth was something scientists already knew, but according to Standford University research associate Norbert Werner – who was one of the scientists tasked with analyzing what little data from Hitomi we have – we now better understand the mechanism the black hole uses to keep the plasma hot enough. Hopefully this allows scientists to unlock more discoveries related to this process as time goes on, but at the very least, it's nice to hear that Hitomi was able to discover something this exciting during its short time in space.

If you're interested in looking at the research for yourself, you can find it in the most recent online edition of Nature, under the title "The quiescent intracluster medium in the core of the Perseus cluster."