The comet looks like a tiny planet about the size of the astronaut's head. It travels with a ghostly white streak trailing behind it. This streak stays the same size as the comet itself moves.
Comets appear in large numbers, making it easier for the astronaut to get hit by one. They circle around planets in a definite path. Often they are arranged in rows and move at different rates on different levels of a large planet. If one hits the astronaut, it will continue traveling in the same direction it was traveling in, but the astronaut will lose one heart or life of health. Although they can be easily tracked one-on-one, their later introduction to the game also means the player has to avoid enemies on other planets while collecting stars on top of the moving comets.