The odd dwarf planet Quaoar might have a brand-new moon. Observations of the tiny world, made by a pair of astronomers in California, suggest it possesses either a second satellite or a third ring.

What makes Quaoar’s ring unique, however, is where it is found relative to Quaoar itself. The Roche limit Any celestial object with an appreciable gravitational field will have a limit within which an ...

The small, faraway world we call Quaoar is pretty peculiar. It is egg-shaped, and it also possesses a moon and two rings. In particular, the rings are where no ring should be; Quaoar is clearly ...