Apollo 11 launch as broadcast live by NASA on July 16, 1969

Bill Shepherd, a former Navy SEAL-turned astronaut who arrived at the International Space Station 20 years ago Monday to begin the continuous occupancy of the orbiting research outpost, says the experience gained by NASA and its global partners over the last two decades provides a blueprint for missions to the moon, Mars, and beyond.

This gallery of U.S. Air Force photos show technicians, wearing protective SCAPE suits, initially check for hazardous hypergolic fuel vapors around the X-37B spaceplane on the Shuttle Landing Facility runway and the subsequent tow of the vehicle to its newly-renovated hangar at the Kennedy Space Center.

A United Launch Alliance Delta 2 rocket fired away from a California military base and disappeared into an overcast cloud deck Saturday on its final flight, carrying a NASA research satellite into orbit and closing the book on a nearly 30-year legacy of launches.