First Truly Isolated Black Hole Discovered In the Milky Way

In our galaxy, there should be 100 million black holes, the most majority of which have masses equivalent to the Sun. However, because no light escapes them, it is difficult to locate them. Normally, they are discovered as a result of star mergers or interactions, but now astronomers have discovered the first-ever fully solitary black hole. Astronomers explain the discovery of the solitary black hole around 5,000 light-years away thanks to the phenomenon of astrometric microlensing in a study submitted to the Astrophysical Journal and awaiting peer review.

Space-time is distorted by gravity. When an object is as dense as a black hole, its gravitational attraction is so intense that it functions as a lens, amplifying and distorting any background light source behind it. This is how certain things are discovered, however because they are so many light-years distant, the effect is tiny, and the star’s light and position must be exceedingly well understood.

The researchers studied a star in the Milky Way’s direction using the Hubble Space Telescope and local observatories. The object’s detailed measurements, which took six years, revealed that the high-magnification microlensing event currently known as MOA-2011-BLG191/OGLE-2011-BLG-0462 was caused by a dense foreground object.

The object’s mass is estimated to be around 7.1 solar masses, plus or minus 1.3 Suns. The study also proved that the object does not emit any light. The mass is greater than that of a neutron star or white dwarf, and the lack of electromagnetic radiation points to a clear and intriguing culprit: a lone black hole travelling through the Milky Way.

Actually, it’s not merely travelling around the galaxy’s center core like the rest of the star system and nebulae. When compared to stars at the same distance, it is traveling at least 45 kilometers (28 miles) per second faster through our galaxy. Because there is a transverse velocity, the real appropriate motion may differ. Nonetheless, despite the limits of the observations, this velocity reveals something. This black hole must have received a massive kick from the supernova explosion that formed it, sending it soaring through the galaxy.

The team emphasizes in the study that while following up on the object will be tough, there is a potential it will show up in deep X-rays or radio studies. Additional excitingly, as next-generation telescopes like as the Vera C Rubin Observatory and the Nancy Grace Roman Space Telescope come online during the next decade, they should detect more microlensing events, some of which could be solitary black holes. It will be much easier to understand the number of these camera-shy objects in our galaxy.