Krypton

Krypton is Duron's only moon. It is the birthplace of a dangerous and powerful substance called Kryptonite. It is also where the Pikmin: Ultimate Doom area Dark Moon takes place.

In Pikmin 3: Dark Matter's Rising
In the game Pikmin 3: Dark Matter's Rising, Krypton returns to find out that Krypton also revolves around The Pikmin Planet, too. It switches orbit every other year, and the year that the game takes place in happens to be the year where Krypton is in The Pikmin Planet's orbit.