Silver Stars are items that first appear in Super Mario 64 DS then later in Super Mario Galaxy, and Super Mario Galaxy 2. They are a weaker type of Star and are Silver color instead of yellow. If all five are collected, they summon a Power Star to come. If the player gets hit by an obstacle or an enemy, a Silver Star bounces out and he/she must collect it again to regain it while it bounces all across the course.
In the Super Mario Galaxy series, some stages contain silver stars scattered around the stage, floating in bubbles unlike in Super Mario 64 DS where they must just be found in areas not in bubbles.