2. Image right: America’s first astronauts: (front row) Walter M. Schirra Jr., Donald K. "Deke" Slayton, John H. Glenn Jr., Scott Carpenter, (back row) Alan B. Shepard Jr., Virgil I. "Gus" Grissom and L. Gordon Cooper. Image credit: NASA

3. Orbit a manned spacecraft around Earth Investigate man's ability to function in space Recover both man and spacecraft safely The first national manned space flight project, later named Project Mercury, was born on Oct. 7, 1958. The program spanned nearly five years, with six manned missions making history between May 1961 and May 1963. In that short time, NASA achieved its goals for the project:

4. Image right: After the last "splashdown" of the Mercury program, Astronaut Gordon Cooper is helped out of his spacecraft, Faith 7, aboard the recovery ship. Image credit: NASA

5. On May 25, 1961, three weeks after Mercury astronaut Alan Shepard became the first American in space, President John F. Kennedy announced the goal of sending astronauts to the moon before the end of the decade. To facilitate this goal, NASA expanded the existing manned space flight program in December 1961 to include the development of a two-man spacecraft. The program was officially designated Gemini on January 3, 1962. Image above: Atlas Agena target vehicle lifts off for Gemini 11 from Pad 14. Once the Agena was in orbit, Gemini 11 rendezvoused and docked with it.

6. The Gemini Program was a necessary intermediate step between Project Mercury and the Apollo Program, and had four objectives: 1) To subject astronauts to long duration flights- a requirement for projected later trips to the moon or deeper space; 2) to develop effective methods of rendezvous and docking with other orbiting vehicles, and to maneuver the docked vehicles in space; 3) to perfect methods of reentry and landing the spacecraft at a pre-selected land- landing point; 4) to gain additional information concerning the effects of weightlessness on crew members and to record the physiological reactions of crew members during long duration flights.

7. "That's one small step for man. One giant leap for mankind." - Neil Armstrong The national effort that enabled Astronaut Neil Armstrong to speak those words as he stepped onto the lunar surface, fulfilled a dream as old as humanity.

8. Project Apollo's goals went beyond landing Americans on the Moon and returning them safely to Earth. They included: Establishing the technology to meet other national interests in space. Achieving preeminence in space for the United States. Carrying out a program of scientific exploration of the Moon. Developing man's capability to work in the lunar environment.

9. Apollo was a three-part spacecraft: the command module (CM), the crew's quarters and flight control section; the service module (SM) for the propulsion and spacecraft support systems (when together, the two modules are called CSM); and the lunar module (LM), to take two of the crew to the lunar surface, support them on the Moon, and return them to the CSM in lunar orbit.

10. Apollo 1 Tragedy Jan. 27, 1967, tragedy struck on the launch pad at Cape Kennedy during a preflight test for Apollo 204 (AS-204). The mission was to be the first crewed flight of Apollo, and was scheduled to launch Feb. 21, 1967. Astronauts Virgil Grissom, Edward White and Roger Chaffee lost their lives when a fire swept through the command module, or CM.

12. The first international partnership in space wasn't the International Space Station. It wasn't even the Shuttle-Mir series of missions. It was the Apollo- Soyuz Test Project, the first international human spaceflight. On July 15, 1975, an Apollo spacecraft launched carrying a crew of three and docked two days later on July 17, with a Soyuz spacecraft and its crew of two.

13. Between the first launch on April 12, 1981, and the final landing on July 21, 2011, NASA's space shuttle fleet -- Columbia, Challenger, Discovery, Atlantis and Endeavour -- flew 135 missions, helped construct the International Space Station and inspired generations. Space Shuttle

14. AtlantisAtlantis | Challenger | Columbia | Discovery | Endeavour Challenger Columbia Discovery Endeavour Atlantis Challenger Columbia Discovery Endeavour Length Space Shuttle: 184 feet Orbiter: 122 feet Height Orbiter on runway: 57 feet Wingspan 78 feet Liftoff Weight* 4.5 million pounds Orbit 115 to 400 statute miles Velocity: 17,321 mph

15. Columbia and the STS-107 crew Columbia and the STS-107 crew Columbia was the first Space Shuttle orbiter to be delivered to NASA's Kennedy Space Center, Fla., in March 1979. Columbia and the STS-107 crew were lost Feb. 1, 2003, during re-entry. The Orbiter Challenger was delivered to KSC in July 1982 and was destroyed in an explosion during ascent in January 1986. Discovery was delivered in November 1983. Atlantis was delivered in April 1985. Endeavour was built as a replacement following the Challenger accident and was delivered to Florida in May 1991. An early Space Shuttle Orbiter, the Enterprise, never flew in space but was used for approach and landing tests at the Dryden Flight Research Center and several launch pad studies in the late 1970s.Columbia and the STS-107 crew