A dormant black hole at least nine times the mass of the Sun orbiting a star has been discovered just 160,000 light-years from Earth.
A team of researchers — known as the “Black Hole Police” for debunking so many black hole discoveries — searched nearly 1,000 stars of the Tarantula Nebula in the Dorado constellation before locating it.
They claim this is the first dormant “stellar-mass” black hole discovered outside the Milky Way.
Stellar-mass black holes are formed when massive stars reach the end of their lives and collapse under their own gravity.
The black hole is said to be “dormant” when it is not actively consuming matter, thereby emitting no light or other radiation.
The discovery has been likened to looking for a “needle in a haystack,” as dormant black holes are notoriously difficult to spot because they don’t interact with their surroundings.
co-author dr. Pablo Marchant from KU Leuven in Belgium said: “It’s incredible, we hardly know any black holes at rest given how common astronomers assume they are.”
Artist’s rendering of the binary star system VFTS 243. Located in the Tarantula Nebula in the Large Magellanic Cloud, the system consists of a hot, blue star with 25 times the mass of the Sun and a black hole at least 9 times the Sun’s mass
Artist’s rendering of the binary system VFTS 243. The background image shows a VISTA (Visible and Infrared Survey Telescope for Astronomy) image of a segment of the Large Magellanic Cloud, marking the region where VFTS 243 resides. The sizes of the star, black hole, and orbits are not to scale
The newly discovered black hole lies in the Large Magellanic Cloud – a satellite galaxy neighboring the Milky Way.
The Large Magellanic Cloud orbits a hot, blue star nearly three times the size of our galaxy.
Thousands of stellar-mass black holes are thought to exist in the Milky Way and the Magellanic Clouds.
They’re a lot smaller than that Supermassive black hole 27,000 light-years from Earth that powers the Milky Way, known as Sagittarius A*.
The black hole is part of a “binary system” with a glowing companion star, where they orbit each other in a system called VFTS 243.
co-author dr. Julia Bodensteiner from the European Southern Observatory (ESO) in Germany said: “We have been searching for such black hole binary systems for more than two years.
“I was very excited when I heard about VFTS 243, which I think is the most compelling candidate yet.”
It took six years of data from ESO’s Very Large Telescope (VLT) to officially identify VFTS 243.
The FLAMES scanner (Fibre Large Array Multi Element Spectrograph) on the VLT enables the simultaneous observation of more than a hundred objects.
In the past, binary stars harboring stellar-mass black holes have been identified by the presence of bright X-ray emissions from the accretion disk.
The glowing accretion disk consists of gases from the living star’s atmosphere pouring toward and surrounding the black hole.
However, observations by NASA’s Chandra X-ray Telescope show that VFTS 243 is X-ray faint.
This image from the VLT Survey Telescope at ESO’s Paranal Observatory in Chile shows the Tarantula Nebula and its surroundings in the Large Magellanic Cloud. It features star clusters, glowing gas clouds, and the scattered remnants of supernova explosions
In the past, binary stars harboring stellar-mass black holes have been identified by the presence of bright X-ray emissions from the accretion disk (pictured). The glowing accretion disk consists of gases from the living star’s atmosphere pouring towards and surrounding the black hole (stock illustration)
The study published today in natural astronomyalso sheds light on how black holes form from the cores of dying stars.
The star that gave birth to VFTS 243 appears to have collapsed completely, leaving no trace of a powerful supernova explosion.
dr Shenar stated, “Evidence for this ‘straight collapse’ scenario has surfaced recently – but our study provides arguably one of the most direct clues.
“This has tremendous implications for the origin of black hole mergers in the cosmos.”
Identifying VFTS 243 took six years of data from ESO’s Very Large Telescope (pictured).
The FLAMES instrument mounted on the Nasmyth A platform on ESO’s Very Large Telescope. FLAMES is a high-resolution spectrograph of the VLT and can access targets through a large corrected field of view. It allows simultaneous observation of more than a hundred objects
Artist’s rendering of NASA’s Chandra X-ray Observatory Space Telescope
Despite the nickname “Black Hole Police,” the international research team actively encourages verification of their work.
lead author dr Tomer Shenar of the University of Amsterdam said: “As a researcher who has been debunking potential black holes for the last few years, I was extremely skeptical about this discovery.
“For the first time, our team came together to report on the discovery of a black hole – rather than reject one.”
dr Kareem El-Badry of Harvard University in Boston is nicknamed the “Black Hole Destroyer” because he is known for debunking discoveries.
dr El-Badry said: “When Tomer asked me to double-check his results, I had my doubts.
“But I couldn’t find a plausible explanation for the data that didn’t include a black hole.
“Of course, I expect other professionals to carefully study our analysis and try to concoct alternative models.
“It’s a very exciting project to be a part of.”
