Astronomers have detected what could be the most massive black hole ever found. The discovery was made using a new method that combines stellar kinematics and gravitational lensing. The cosmic horseshoe, one of the largest galaxies ever discovered, is believed to be home to this ultra-massive object (UMBH).
The UMBH has an estimated mass of 36 billion solar masses, making it potentially the most massive black hole detected so far. However, scientists are cautious due to uncertainties in measuring black hole masses.
Stellar kinematics, which tracks the motion of stars near a black hole, is considered the most accurate method for determining a black hole’s mass. This method was used to measure the mass of the Milky Way’s supermassive black hole (SMBH) and its companion star system, Sagittarius A-star.
However, stellar kinematics becomes challenging when measuring distant black holes due to the small size of galaxies in the sky. Gravitational lensing, which amplifies light from a background object, overcomes these limitations.
The Cosmic Horseshoe’s unique gravitational lens, known as a radial arc, allowed researchers to detect and measure the UMBH’s mass. The detection method involves analyzing the motion of stars within the galaxy and tracking how light from the black hole is affected by its gravity.
“This discovery was made possible by combining strong lensing with stellar dynamics,” said lead author Carlos Melo. “We’ve got a much more certainty about the mass of this black hole thanks to our new method.”
The UMBH’s mass suggests that it is part of a fossil group of galaxies, which are remnants of early galaxy mergers. The massive object likely formed when multiple galaxies merged, resulting in the formation of an ultra-massive black hole.
Future telescopes will provide more opportunities for analyzing radial arcs and gaining insights into ultra-massive black holes. The study’s findings shed light on the relationship between a supermassive black hole’s mass and its host galaxy, as well as the potential for new discoveries in the field of astronomy.
Source: https://www.universetoday.com/articles/a-36-billion-solar-mass-black-hole-detected-thanks-to-gravitational-lensing