Scientists have found a tiny black hole that lies close to a star in the constellation Ophiuchus around 1,600 lightyears away. It’s the closest back-hole to Earth.
Black holes are among the densest objects in the Universe (neutron stars). Whether tiny, stellar-mass black holes or supermassive ones located in the central regions of galaxies, these objects possess gravitational fields that are so strong that even light particles can pass through the horizons.
The newly discovered black hole, named Gaia BH1 — is nearly three times farther from Earth than the former record-holder. The details of its discovery and information about the Sun-like star which orbits it was released last week by the Monthly Notices of the Royal Astronomical Society.
It was first discovered with its Gemini North telescope in Hawaii, one of the International Gemini Observatory, combined with data from NASA’s Gaia spacecraft. The Gaia data showed that the star’s motion was unusual for a single object. Instead, it appeared like the gravitational force of a massive thing was the cause of its motion.
The follow-up observations of Gemini North were done to determine the exact orbital duration of the star’s companion, which helped the team estimate the size of the unobserved object.
“While there have been many claimed detections of systems like this, almost all these discoveries have subsequently been refuted,” said Kareem El-Badry, an astrophysicist with the Center for Astrophysics | Harvard and Smithsonian and the paper’s principal author, in a NOIRLab press release. “This is the first unambiguous detection of Sun-like star in a wide orbit around a stellar-mass black hole in our Galaxy.”
Remember that the lightyear equivalent to approximately 6 trillion miles. So at 1,600 lightyears away, the black hole that is nearby is only somewhat close. Voyager is the most distant space mission in human history. It has been accelerating off Earth for over fifty years and is only fifteen billion miles from Earth.
Since light can’t escape from black holes, they’re best observed when enclosed by the superheated matter they’ve accreted. This is the case with this black hole near the middle of Messier 1987 and Sagittarius A, which is the black hole that lies at the heart of the Milky Way. Both black holes were photographed with the help of the Event Horizon Telescope Collaboration because of the glowing matter that allows us to discern the dark hole’s location.
Black holes are more challenging to detect when they’re not actively feeding. They’re not expanding material, superheating the matter, and releasing X-rays as with Gaia BH1, which is invisibly visible, aside from the gravitational effects it exerts on the star.
“Our Gemini follow-up observations confirmed beyond reasonable doubt that the binary contains a normal star and at least one dormant black hole,” El-Badry declared. “We could find no plausible astrophysical scenario that can explain the observed orbit of the system that doesn’t involve at least one black hole.”
Monitoring further binaries of black holes will assist astrophysicists in refining their models for how such systems develop and develop. Space telescopes like IXPE and NASA’s NICER, and NuSTAR can assist in these endeavors by studying the X-rays that emit high energy from the black holes they feed.