Using NASA’ Hubble Telescope, a team of astrophysicists and astronomers has found in the core of the dwarf galaxy Markarian 231 (Mrk 231) — also known as UGC 8058 — a binary black holes orbiting furiously around each other.
Quasars (‘quasi-stellar radio sources’) are among the most energetic and brightest known objects in cosmos. Also named active galactic nuclei, these objects can be 100 times brighter than the entire Milky Way galaxy. Their power and their extreme luminosity are driven by monster black holes which eject all of the particles that don’t fall into their depths outward at nearly the speed of light.
The quasar at the center of Markarian 231 was discovered in 1969. It located 600 million light-years away from us and its the nearest quasar to Earth.
Previous observation, based on Hubble data, showed a mysterious hole in the quasar’s accretion disk — a structure of superheated gases surrounding the central region. But later, by studying the ultraviolet emissions blasting from the quasar, a deeply fascinating discovery was made.
In the new research, conducted by Dr. Youjun Lu, scientists looked at UV radiation emitted from the center of the dwarf galaxy Markarian 231 from Hubble archival observations, then applied a model developed by Dr Lu to the spectrum of the galaxy. As a result, scientists concluded that the system must be made of two black holes: a large one and a small one orbiting each other.
We are extremely excited about this finding because it not only shows the existence of a close binary black hole in Markarian 231, but also paves a new way to systematically search binary black holes via the nature of their UV light emission,
said Dr Lu.
The structure of our Universe, such as those giant galaxies and clusters of galaxies, grows by merging smaller systems into larger ones, and binary black holes are natural consequences of these mergers of galaxies,
added Prof. Xinyu Dai ~ co-author of the study.
From scientists calculations, it estimated that the larger black hole from the pair is approximately 150 million times sun’s mass and its smaller companion is just 4 million solar masses. They are completing one orbit around each other every 1.2 years. Scientists estimate that it will take hundreds of thousands of years for the larger black hole to swallow smaller one.
What does this existence of these binary black holes mean to Earth? For now, not much. Regardless of what the future will bring, this study certainly reveals some of the keys to the evolution of these young galaxies.
Preprint paper: arxiv.org.
© Content from this site must be hyperlinked when used.