Geronimo Stilton Spacemice #7: Beware! Space Junk!

MouseStar 1 is surrounded by floating space junk! It's gross - and dangerous. Geronimo Stiltonix discovers that it comes from wasteful aliens on a nearby planet. Even worse, robots that the aliens have thrown in the trash have started to rebel. It's up to the spacemice to restore harmony on the planet. . . and help them clean up!