IC 10 X-1

The galaxy IC 10 is small but busy. It’s only a few thousand light-years across — a small fraction of the size of the Milky Way. But pound for pound, it’s giving birth to more stars than the Milky Way is. Many of those stars are big, bright, and heavy. At the ends of their short lives, they’ll explode. The cores of some of those stars will collapse to form black holes.

One system in the galaxy consists of a current black hole and a future one. IC 10 X-1 was the first source of X-rays discovered in the galaxy. The X-rays come from a “wind” of hot gas from the bright star, plus a disk of hot gas around the black hole.

Early observations indicated the black hole was about 15 times the mass of the Sun, with its companion about 25 times the Sun’s mass. But more recent work has found the masses a little tougher to pin down.

The companion appears to be heavy enough to explode as a supernova, leaving behind a second black hole. The blast may send the star and the current black hole racing away from each other. If they stick together, though, in a few billion years they’ll merge — forming an especially heavy black hole.

IC 10 is in Cassiopeia, which is low in the northeast in early evening and overhead at first light. IC 10 is near the top right point of the “W” that outlines the queen. The galaxy is a couple of million light-years away — quite close as galaxies go. But it’s so faint that you need a telescope to see it.
 

Script by Damond Benningfield