Space scientists seem to have discovered the smallest black hole ever to get detected till now that might come under a totally different class of objects. The researchers at Ohio State University were studying a huge star and a companion, which they claim happens to be the smallest black hole ever.
For long, black holes were estimated to exist in two ranges of size. There are black holes that have a mass ranging between five to 30 times that of the Sun and are termed as stellar black holes. On the other hand, there are supermassive black holes that have a mass equivalent to a few million suns.
Now, there is a gap between these two types of black holes, which scientists believe are filled to be filled by black holes which have masses between 100 and 10,000 suns. Such types of black holes are called intermediate-mass black holes, according to a report by New Atlas.
There is a new theory according to scientists that when the stars collapse under their own gravity, either they form black holes or energetic neutron stars. There seems to be a limit of 2.1 solar mass under which a collapsing star turns into a neutron star, however, if it is over that limit, then it transforms into a black hole.
The researchers at Ohio State University looked for the black holes that fall in this new category. They looked at a binary star system which is made of the star 2MASS J05215658+4359220 and its companion. Through a unique approach, they found that this particular companion is a likely black hole with low mass. Their research got published in the Science journal.
To look for this hidden black hole, the researchers had to carefully search through the data gathered by Apache Point Observatory Galactic Evolution Experiment (APOGEE), which is meant for measuring the light spectra of stars. They were observing the changes in light from stars that may indicate that they are orbiting around some unseen object.
The researchers focused on 200 stars out of approximately 100,000 stars available. After this, they compiled the images of each star from the All-Sky Automated Survey for Supernovae. From here, they zeroed in on one huge star 2MASS J05215658+4359220 which looked like it was orbiting some invisible object. On examining it further the researchers calculated a probable black hole having 3.3 solar masses.
“What we’ve done here is come up with a new way to search for black holes, but we’ve also potentially identified one of the first of a new class of low-mass black holes that astronomers hadn’t previously known about,” Todd Thompson, a professor of astronomy at The Ohio State University and lead author of the study said in a statement. “The masses of things tell us about their formation and evolution, and they tell us about their nature.”