A distant star in the cluster NGC 3201 that’s exhibiting odd behavior may be drawing attention to a secret. A team of international astronomers thinks it’s behaving that way because the star is orbiting a black hole that has four times the mass of the sun.
The team saw the star moving backward and forward at speeds of several hundred kilometers per hour, in a cycle that repeats every 167 days. [The Strangest Black Holes in the Universe]
“It was orbiting something that was completely invisible, which had a mass more than four times the sun — this could only be a black hole,” Benjamin Giesers, lead author on the new research and an astrophysicist with the University of Göttingen in Germany, said in a statement.