The Roaming Black Hole

By Anya Geiling

Astronomers have identified 13 massive wandering black holes in dwarf galaxies less than 1 billion light-years from Earth ( One of them, called B3 1715+425, started out normal. Now, it’s hurtling through space at 2,000 kilometers per second. 

To begin, a black hole is a place in space where gravity is so strong that nothing leaves it. Not even light can escape from this gravitational monster. Black holes have a radius at roughly 12 million kilometers. Earth has a radius of 3,958.8 miles. That is a dramatic difference. 

Ok, but let’s get back to the black hole on the run. B3 1715+425 started out just like any other black hole with a galaxy full of stars around it. Astronomers, however, have proved otherwise. The black hole was stripped, essentially naked, bolting through space at astronomical speeds. It doesn’t seem to be slowing down. 

This black hole in particular is supermassive, which in definition can be millions or billions times larger than our Sun. Black holes are commonly found to be at the center of most galaxies (ours included). James Condon, a lead researcher from the National Radio Astronomy Observatory stated that this roaming black hole instead fled from its larger galaxy and left a trail of debris behind it. But what happened to B3 1715+425’s galaxy? Why did it disappear?

It turns out that galaxies collide. When they do, the black holes at the center of each galaxy combine and become one larger mass. When B3 1715+425 had a galaxy, it seemed to have collided with a much larger galaxy, therefore a much larger black hole. Instead of coming together, the larger black hole destroyed B3 1715+425’s galaxy. B3 1715+425 managed to escape and is slowly losing the stars that feed it. All of this happened over millions of years ago. As of now, B3 1715+425 is still hurtling through space. If it comes our way, we’re in big trouble.