A team of astronomers from across the world has used more than 500 images from NASA’s Hubble Space Telescope that had been collected from 1995-2015 on the hunt for the IMBH in the Omega Centauri, a globular cluster. Using the motion of seven stars in the cluster’s concentration zone and detecting the effect similar to that of a heavy massive black hole nearly a hundred million light-years away from Earth or cataloging the trajectories of thousands of other stars, the team has obtained encouraging evidence proving the existence of an IMBH.
Compelling Evidence
This means these stars move in an atypical way from which the scientists concluded they are affected by a strong mass, most probably in the form of IMBH. Up to now, only few other IMBH candidates have been detected. It is omega centauri about ten times as large as the average globular cluster and containing of the order of ten million stars and almost as massive as a small galaxy.
Key Questions in Black Hole Research
The specific interest in IMBHs includes the statistics on their presence, how they came to form and if indeed they are developmental stages of SMBHs. Furthermore, they intend to find out if dense star clusters are the preferred home to IMBH.
Extensive Star Catalog
At the moment, the astronomers have amassed a gargantuan amount of data regarding stars’ motions, or known as velocities for 1. Filled with 4 million stars captured with the help of the Hubble telescope. Of these observations made mainly for accuracy control of the instruments, the number seemed most useful to the team’s studies
Unexpected Discoveries
Maximilian Häberle, of the Max Planck Institute for Astronomy in Germany and the head of the study, detailed the importance of the discovery. Seven stars shouldn’t be there, Häberle observed. The most plausible reason is that some very massive object is thus tugging on these stars, and keeping them in the vicinity of the centre: just one body can be sufficiently large to meet that requirement: a black hole, with a mass of at least 8,200 Suns.
Conflicting Theories
Previous works was devoted to the attempt to detect an IMBH in Omega Centauri while others indicated that the cluster mass could be explained by a dense central group of stellar-mass black holes. The absence of O-stars with velocities higher than the escape velocity had in fact ruled out the possibility of an IMBH compared to this.
Significant Discovery
This the first direct finding of IMBH in Omega Centauri, according to the lead researcher Nadine Neumayer from Max Planck Institute for Astronomy. Anil Seth from the University of Utah, Salt Lake City was contacted in the study by Neumayer. ”This is rather encouraging as there are barely any other black holes of similar mass identified to date; the black hole in Omega Centauri may well be the best example of an IMBH in our local universe.”
Closer to Home
If true, this candidate black hole, some 17,700 light years away from Earth, would be located nearer us than the 4. It shows even the 3 million solar mass black hole at the heart of the Milky Way, 26000 light years from us.
A Celestial Marvel
The moving of Omega Centauri is well observed in the southern sky by amateurs that try to catch lucky sight of it. From the dark areas of the rural or countryside the cluster can be seen with the naked eye as large as a full moon. Ptolemy registered this celestial object 2000 years ago and classified it as a single star, but later, in 1677, Halley discovered it as a nebula; in the 1830 s, Herschel as a globular cluster.
References:
- Fast-moving stars around an intermediate-mass black hole in ω Centauri
Strong evidence for intermediate-mass black hole in Omega Centauri
