Watch a NASA astronaut on board the International Space Station demonstrate centripetal force by swirling a tethered tool around a cord, rotating a bag of tea to demonstrate that the air bubbles are pushed toward the center, and spinning a water droplet to show its deformation based on centripetal force. In this video from NASA's Teaching from Space program, learn more about the force that keeps the planets in orbit around the Sun, keeps the moon in orbit around the Earth, and keeps roller coasters secure as they loop and curl.