The black hole, located in a galaxy called UHZ1 about 13.2 billion light-years from Earth, was discovered by a team led by Akosh Bogdan, a scientist at the Harvard-Smithsonian Center for Astrophysics in the United States. Black holes formed when the universe was only 3% of its present age.
After more than two weeks of observations using the Chandra probe, the researchers discovered the presence of intense, superheated, X-ray-emitting gas in the galaxy, a hallmark of a growing supermassive black hole.
Based on features such as X-rays emitted by the black hole as it gobbled up material around it, the researchers estimated the mass of the black hole to be between 10 and 100 million solar masses. The researchers say the evidence suggests that the black hole was massive from birth, with a mass close to that of all the stars in its galaxy combined. But in nearby regions of the universe, the mass of black holes in galaxies tends to be much smaller than the total mass of the stars in them.
The researchers believe that the black hole's signature supports a theory previously proposed by some astronomers that massive black holes formed when giant nebulae collapsed in the early universe. The researchers plan to further analyze the data to delve deeper into the mysteries of the early universe.
Microquasar is a binary star system composed of a neutron star or black hole and an ordinary star in the Milky Way galaxy. The neutron star or black hole accrets the material of the star to produce a high-temperature accretion disk and relativistic jets, which are observed as intermittent or long-term changes in X-ray and radio radiation. It is a natural laboratory of the universe to study the strong gravitational field and relativistic physics. GRS 1915+105 is a well-known microquasar containing a rapidly rotating black hole and observed faster-than-light radio jets, and is an important sample for the study of extremely high-energy physical processes. For more than 30 years since its discovery, the black hole has been characterized by abundant X-ray light variability and intermittent radio jets, but the dynamics of the black hole jets and the origin of the rapid light variability remain unclear.
In order to uncover the mystery of the relativistic jets of microquasars, an international collaborative research team has used FAST to conduct the first high time precision radio continuous spectrum light variation and polarization monitoring of GRS 1915+105 from 2020 to 2022. Taking advantage of FAST's high sampling and detection sensitivity, two observations in January 2021 and June 2022 found that the black hole has a faint radio pulse with a pulse period of about 0.2 seconds. This pulse cycle is unstable and undetectable most of the time, so it is called a quasi-periodic oscillation. In the collaborative research results, Tian Pengfu, Dr. Zhang Ping, Professor Wang Wei and Associate Researcher Wang Pei from Wuhan University are co-first authors, and Liu Jifeng, Jiang Peng and Li Di from the National Astronomical Observatories are co-authors.
This is the first international observation of quasi - second low frequency radio oscillations of microquasars, and reveals that the quasi - periodic oscillations of black hole systems are directly related to relativistic jets. The discovery of the pulse of black hole radio radiation is of great scientific significance for revealing the origin and dynamics of relativistic radio jets of compact celestial bodies, and will open new ideas for black hole radio observation and theoretical research.