THERE may be two giant black holes lurking in the middle of our galaxy, instead of just one. Astronomers reckon that a middleweight black hole, thousands of times heavier than the sun, is dragging young stars towards the monster black hole known to sit at our galaxy’s centre. The discovery could help explain how the monster grew so fat in the first place.
There is good evidence that most, if not all, large galaxies harbour a supermassive black hole. The one at the centre of the Milky Way is about three million times as massive as the sun. Astronomers believe…
