Smallest Space Vacuum Found Not Made by Hoover

Astronomers have found the smallest black hole yet. It is only 3.8 times the mass of our own sun with a diameter of 15 miles. This black hole is very close to the minimum size astronomers predict possible to even occur.

The two astronomers, Nikolai Shaposhikov and Lev Titarchuk work at NASA’s Goddard Space Flight Center in Greenbelt, MD. They found the black hole in the Milky Way in the binary system XTE J1650-500 (catchy name!).

According to Shaposhikov, "this black hole is really pushing the limits. For many years astronomers have wanted to know the smallest possible size of a black hole, and this little guy is a big step toward answering that question."

The two figured out the size of the black hole by using a new technique. They used the relationship between a black hole and dust that surrounds it and swirls downward. This dust tends to pile up at the edges and turns into hot gas, which radiates X-rays. These X-rays have a pretty regular pattern of intensity that the astronomers can view.

It was previously thought that these oscillations depended on the size of the black hole. Titarchuk realized that the larger the hole, the further the hot gas is pushed out, so the oscillations go slower and slower. The two astronomers used a database of information of other black holes and their oscillations to calculate the size of this new, very small black hole.

Apparently small black holes can exert stronger tidal forces than the larger ones, so no black hole is a “safe” black hole. "If you ventured too close to J1650's black hole, its gravity would tidally stretch your body into a strand of spaghetti," says Shaposhnikov.