This sterling silver charm is the NASA disk. It is 13 mm in diameter. In the NASA insignia (meatball) design, the sphere represents a planet, the stars represent space, the red chevron is a wing representing aeronautics (the latest design in hypersonic wings at the time the logo was developed), and then there is an orbiting spacecraft going around the wing.In the NASA insignia (meatball) design, the sphere represents a planet, the stars represent space, the red chevron is a wing representing aeronautics (the latest design in hypersonic wings at the time the logo was developed), and then there is an orbiting spacecraft going around the wing.