The behemoth, which is presently following an orbit that lies within those of Earth and Venus, is around 0.9 miles wide – about a sixth of the diameter of the asteroid believed to have killed off the dinosaurs.

​The behemoth, which is presently following an orbit that lies within those of Earth and Venus, is around 0.9 miles wide – about a sixth of the diameter of the asteroid believed to have killed off the dinosaurs.