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.

Quaoar and our solar system's other dwarf planets are generally so far away that they are a challenge to view directly from Earth. (An exception is Ceres, which lies in the main asteroid belt between Mars and Jupiter.) So, to observe them, astronomers rely on stellar occultations — moments when an object passes between them and a background star. The body of the foreground object briefly blocks light from the star, as do any rings or satellites.

Both of Quaoar's known rings were discovered in separate occultations, with the first ring initially identified by a trio of amateur astronomers.

But

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