(Nanowerk News) Researchers have observed X-ray emission from the brightest quasar seen in the last 9 billion years of cosmic history, known as SMSS J114447.77-430859.3, or J1144 for short. New perspectives shed light on how quasars work and how they interact with their environment.
This research was published in Monthly Notices of the Royal Astronomical Society (“First X-ray look at SMSS J114447.77-430859.3: brightest quasar in last 9 Gyr”).
Guided by a galaxy 9.6 billion light years away from Earth, between the constellations Centaurus and Hydra, J1144 is immensely powerful, shining 100,000 billion times brighter than the Sun. J1144 is much closer to Earth than other sources of the same luminosity, allowing astronomers to gain insight into the black hole driving the quasar and its surroundings. The study was led by Dr Elias Kammoun, a postdoctoral researcher at the Research Institute in Astrophysics and Planetology (IRAP), and Zsofi Igo, a PhD candidate at the Max Planck Institute for Extraterrestrial Physics (MPE).
Quasars are among the brightest and most distant objects in the known universe, powered by the falling of gas into supermassive black holes. They can be described as very high-luminosity active galactic nuclei (AGNs) that emit large amounts of observable electromagnetic radiation in the radio, infrared, visible, ultraviolet, and X-ray wavelengths. J1144 was initially observed in visible wavelengths in 2022 by the SkyMapper Southern Survey (SMSS).
For the study, the researchers combined observations from several space-based observatories: the eROSITA instrument aboard the Spectrum-Roentgen-Gamma (SRG) observatory, ESA’s XMM-Newton observatory, NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR), and NASA’s Neil Gehrels. Fast observatory.
The team used data from four observatories to measure the temperature of the X-rays emitted from the quasar. They found this temperature to be around 350 million Kelvin, more than 60,000 times the surface temperature of the Sun. The team also found that the mass of the black hole at the center of the quasar is about 10 billion solar masses, and that it is growing at a rate of up to 100 solar masses per year.
X-ray light from this source varies on time scales of several days, which is not normally seen in quasars with black holes as large as the one in J1144. The typical time scale of variability for a black hole of this size would be on the order of months or even years. Observations also show that while some of the gas is swallowed up by the black hole, some of the gas is expelled in the form of very strong winds, injecting huge amounts of energy into the host galaxy.
Dr. Kammoun, lead author of the paper, said, “We were very surprised that no previous X-ray observatory had observed this source despite its extraordinary power.”
He added, “Similar quasars are usually found at much greater distances, so they appear much dimmer, and we look at them as they did when the universe was only 2-3 billion years old. J1144 is an extremely rare source because it is so luminous and much closer to Earth (though still at a great distance!), giving us a unique glimpse into what such a powerful quasar could look like.”
“A new monitoring campaign of this source will start in June this year, which may reveal more surprises from this unique source.”