Sling Star

From the Super Mario Wiki

A Sling Star is a miniature Launch Star item found in Super Mario Galaxy. Like Launch Stars, they give Mario boosts into the air. However, these do not send Mario flying into space with power. They simple give him a small fling into the air to reach other platforms and areas.

In some situations, there will be Sling Stars that will throw Mario up to a higher Launch Star, so he can use that to go to another planet; in other situations, the Sling Stars will bounce Mario to other nearby planets instead of farther away ones.

In the Good Egg Galaxy, during the mission "A Snack Of Cosmic Proportions", the player will encounter a planet that looks very much like a Sling Star.