NASA scientists have identified the smallest black hole ever found -- less than four times the mass of our sun and about the size of a large city.
The mini-black hole - J1650 - is really pushing the limits. Astronomers have wanted to know the smallest possible size of a black hole, and this ls a big step toward answering that question.
Formed by a star that ran out of fuel and shut down, collapsing due to its own gravity, this phenomenon was found in a system in the southern constellation Ara, in our own Milky Way Galaxy.
The new black hole has a mass of 3.8 Suns and would be about 15 miles across, making this black hole one of the smallest objects ever discovered outside our solar system.
The smallest black hole previously identified was GRO 1655-40, with a mass of about 6.3 Suns.
Amazingly, equations from Albert Einstein predict that a black hole with 3.8 times the mass of our Sun would be only 15 miles across -- the size of a city.
A collapsing star that was much smaller than J1650 would likely form a neutron star and not a black hole.
