Students assemble balloon race cars and Alka-Seltzer film canister rockets to demonstrate Newton's third Law of motion at the NASA Science Gallery at Union Station, Monday, April 22, 2013 in Washington. The NASA Science Gallery exhibits are being sponsored by NASA in honor of Earth Day. (Photo Credit: NASA/Carla Cioffi)
Photographer NASA/Carla Cioffi
Date April 22, 2013