The supermassive black hole in the center of the Milky Way is spinning so quickly it is warping the spacetime surrounding it into a shape that can look like a football, according to a new study using data from NASA’s Chandra X-ray Observatory and the National Science Foundation’s Karl G. Jansky Very Large Array (VLA).
Astronomers call this giant black hole Sagittarius A* (Sgr A* for short), which is located about 26,000 light-years away from Earth in the center of our galaxy.
Black holes have two fundamental properties: their mass (how much they weigh) and their spin (how quickly they rotate). Determining either of these two values tells scientists a great deal about any black hole and how it behaves.
A team of researchers applied a new method that uses X-ray and radio data to determine how quickly Sgr A* is spinning based on how material is flowing towards and away from the black hole. They found Sgr A* is spinning with an angular velocity — the number of revolutions per second — that is about 60% of the maximum possible value, a limit set by material not being able to travel faster than the speed of light.
In the past, different astronomers made several other estimates of Sgr A*’s rotation speed using different techniques, with results ranging from Sgr A* not spinning at all to it spinning at almost the maximum rate.