When America Went to the Moon
The cold war inspired it, big bucks backed it and Yankee ingenuity made it happen; 25 years later, the footprints in the lunar dust still inspire awe
Lift off from Earth
1. Liftoff (July 16, 9:32 a.m. EDT). Five large engines on the first stage, with a combined thrust of 7.6 million pounds, ignite to lift Saturn 5 to altitude of over 40 miles.
2. Second stage. Five smaller engines burn 6 1/2 minutes to propel the spacecraft more than 100 miles above the earth and over 1,000 miles downrange.
3. Third stage. Engine burn puts Apollo 11 in a "parking orbit" around the Earth.
Leaving Earth orbit
4. To the moon. After 1 1/2 Earth orbits, the third stage fires to send Apollo 11 toward the moon.
5. Docking. Apollo 11 crew separates command and service module from section housing the lunar module, turns around and docks with it. Third stage discarded.
Cruising toward the moon
6. Barbeque mode. For 73 hours, Armstrong, Aldrin, and Collins coast toward the moon, targeted so accurately that only one of four planned four course corrections is needed. The spacecraft rotates slowly in "barbeque mode" so the sun's rays heat it evenly.
7. Lunar orbit. Command module engine burns to slow craft so it swings into orbit around the moon.
Lunar landing
8. Separation. Armstrong and Aldrin in lunar module ("Eagle") separate from command module ("Columbia"), leaving Collins behind in lunar orbit.
9. Descent. Going behind the moon, Eagle fires descent engine, sending it toward the surface.
10. Landing. With 20 seconds' fuel remaining, "The Eagle has landed."
Homeward bound
11. Ascent. After 22 hours on the moon, Eagle lifts off to rejoin Columbia. . 12. Reunion. With all three crew members again aboard, command module lights its engine for the trip home. Eagle is left behind in lunar orbit
Back to Earth
13. Re-entry. Minutes from re-entry, service module ejects and command module turns so that its blunt heat shield faces Earth for reentry into atmosphere.
14. Splashdown (July 24, 12:51 p.m. EDT) Apollo 11 splashes down safely in South Pacific, and the USS Hornet picks up crew. To guard Earth against possible contamination, the astronauts spend next 17 days in quarantine.
Troubled landing As soon as Eagle began its descent to the moon's rocky surface--the most perilous part of the mission--alarms began flashing. The main computer was overloaded, raising fears that the landing would have to be aborted. Again and again the alarms went off, and Houston said go. Eagle had overshot the intended landing zone by 4 miles, and its computer was blindly leading Armstrong and Aldrin into a field of boulders. Armstrong took over the controls, searching for a clear place to land. Finally, with only 20 seconds of fuel remaining, Armstrong deftly set his machine on the moon.
MOON SUIT: Communications antenna; Portable life-support system; Helmet and visor; Integrated thermal micrometeoroid garment; Communication, oxygen, and cooling umbilical connectors; Remote backpack control unit; Lunar overshoe
Laser reflector With laser beamed from Earth, reflector allows scientists to measure accurately the distance to moon and continental drift on Earth.
LUNAR MODULE (LM): S-band and radar antenna; Forward entrance hatch; Descent stage; Descent engine; Surface sensing probe; Reaction control system thrusters; Ascent stage; Docking tunnel
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