This is the era of space exploration, and we couldn’t be happier to hear the words exoplanet, black hole, and habitable world every few days. Now, to study has observed a Sun-like star with a strange orbit.
The star’s orbital characteristics are so strange that scientists think it must be part of a black hole binary system. If this international team of researchers is correct, this makes it the nearest black hole to our solar system.
In addition, this discovery implies that there ought to be many dormant black holes spread across the Milky Way galaxy, the home of Earth. Led by researchers from various institutes like Harvard-Smithsonian Center for Astrophysics, UC Berkeley, Caltech; the study was published in the Monthly Notices of the Royal Astronomical Society.
Discovering dormant black holes
Kareem El-Badry, a Harvard Society Fellow, explained to Universe Today that these observations were part of a larger campaign to identify dormant black hole companions to normal stars in our galaxy.
“I’ve been searching for dormant black holes for the last four years using a wide range of datasets and methods,” he said. “My previous attempts turned up a diverse menagerie of binaries that masquerade as black holes, but this was the first time the search has borne fruit,” he added.
The team used data obtained by the European Space Agency’s (ESA) Gaia Observatory to study the dormant black hole. The mission has been in motion for a decade; measuring the positions, distances, and motions of over a billion cosmic objects, be it stars, planets, asteroids, and galaxies.
Researchers examined 168,065 stars in the Gaia Data Release 3 (GDR3) that seemed to have two-body orbits. It was then that they stumbled on the star designated Gaia BH1 by scientists. Based on its orbit, they determined that the star must have a black hole binary companion.
This could be the first time that a black hole was observed in the Milky Way without using X-ray emissions or other energetic releases. “Models predict that the Milky Way contains about 100 million black holes. But we’ve only observed about 20 of them. All the previous ones we’ve observed are in ‘X-ray binaries’: the black hole is eating a companion star , and it shines brightly in X-rays as that material’s gravitational potential energy is turned into light, “El-Badry was quoted by Science Alert.
“But these only represent the tip of the iceberg: a vastly larger population may lurk, hidden in more widely separated binaries. The discovery of Gaia BH1 shines early light on this population,” El-Badry added.
The study was posted on pre-print portal arXiv and is awaiting peer review.
Today, U. (2022, September 20). The Orbit of a Sun-Like Star Reveals The Nearest Black Hole Ever Found: ScienceAlert. Retrieved September 21, 2022, from https://www.sciencealert.com/the-orbit-of-a-sun-like-star-reveals-the-nearest-black-hole-ever-found