In February 2016, Japan launched a revolutionary black-hole-monitoring satellite but right after the successful launch, they lost its control under unknown situations. Now, we can finally see what Hitomi saw just before it went offline. When Hitomi went offline, scientists were successful receiving some data from Hitomi, which was published a few days ago in a newspaper in Nature.
Data shows Hitomi’s last observation. It has some very interesting suggestions for what we currently know about the role of black holes in the formation of a galaxy.
Hitomi’s last observations (Image Credit: Hitomi Collaboration/JAXA, NASA, ESA, SRON, CSA) Hitomi’s last observations were of the Perseus Cluster, a giant galaxy cluster about 240 million light years away from having a supermassive black hole at its center. Hitomi was able to capture this incredible view of the galaxy (shown above), plus to an extent its x-ray activity. Researchers were expecting to detect teeming activity at the center of the cluster, but Hitomi’s last x-ray observations showed very little action.
Co-author of this new research paper, Andrew Fabian from University of Cambridge stated to Gizmodo:
“The intracluster gas is fainter than previously expected. We were expecting the level to be higher because of the activity at the central galaxy.”
But this result is not just an amazing shelter of calm in a stormy galaxy. It also gives us an idea about what role black holes play in how galaxies do—or don’t—form.
“The shock is that it turns out, the energy being emitted from the black hole is being efficiently absorbed,” co-author Brian McNamara of the Waterloo University told Gizmodo. “This hot gas that we’re watching at with Hitomi is the stuff of the future; it’s the gas out of which galaxies are made of. There is far more of this hot gas than there are stars in the galaxy, or there is more stuff that was not made into galaxies than that was.”
That means that nearby black holes play a vital role in the ultimate size of a galaxy. McNamara said:
“What it indicates is that black holes very efficiently control the growth rate of galaxies.”
Obviously, the discovery highlights how little we know about the role of black holes in the formation of a galaxy. It also gives us a tempting look at how much promise the satellite held before it went offline.
The loss is even bigger because Hitomi noticed what scientists hoped would be an end of a long-standing struggle to finally stick an x-ray microcalorimeter (a device used to take extremely precise measurements of the energy in x-rays—into space). The discovery in today’s study was based on just a very little sample of data scientists were able to get from Hitomi’s microcalorimeter before it went offline, and it already has them wondering what could have been.
“The measurements on the Perseus Cluster indicated the potential of the Hitomi x-ray microcalorimeter to transform our knowledge of the velocities of hot gas throughout the Cosmos.”
Before Hitomi, there were two other efforts to send a microcalorimeter into space—and both ended in unusual accidents. In 2000, a rocket mission that would have been the first one to send a microcalorimeter into space exploded upon launch. In 2005, a microcalorimeter really made it into space but was wrecked by a coolant leak. It wasn’t until 2016 with Hitomi that a microcalorimeter was successfully launched long enough to take readings—only to be lost along with the whole satellite shortly after.
Featured Image Explanation: This image illustrates how supermassive black holes at the center of galaxy clusters could heat intergalactic gas, preventing it from cooling and forming stars. The black hole inflates bubbles (dark areas) of ultrahot, ionized gas, called plasma. The bubbles, which reach tens of thousands of light-years into space, drag gas (blue clouds) from the cluster center, which explains the long streaks of gas, or filaments, seen in optical images. In the outer regions, the bubbles cause turbulence, which heats the gas. The hot gas emits bright X-rays detected by X-ray satellites.