Nasa hosts moonbuggy race in Alabama
Teams from around the world have descended on Huntsville, Alabama for Nasa's annual Great Moonbuggy Race.
More than 500 high school and college students competing in human-powered vehicles were inspired by the lunar rovers that astronauts used on the moon.
They have to complete a half-mile race course - navigating obstacles on the way which are designed to simulate the surface of the moon - in the fastest time.
Diedra Williams, the Great Moonbuggy Race Project Manager, said the event was a learning experience as well as a fun one.