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'Edited highlights of film footage transferred to HDTV by the Discovery Channel for their NASA Greatest Missions... programs.'
Originally a public domain film from NASA, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied.
https://en.wikipedia.org/wiki/Apollo_program
Wikipedia license: http://creativecommons.org/licenses/by-sa/3.0/
The Apollo program, also known as Project Apollo, was the third United States human spaceflight program carried out by the National Aeronautics and Space Administration (NASA), which succeeded in landing the first humans on the Moon from 1969 to 1972. First conceived during Dwight D. Eisenhower's administration as a three-person spacecraft to follow the one-person Project Mercury which put the first Americans in space, Apollo was later dedicated to the national goal set by President John F. Kennedy of "landing a man on the Moon by the end of this decade and returning him safely to the Earth" in an address to Congress on May 25, 1961. It was the third US human spaceflight program to fly, preceded by the two-person Project Gemini conceived in 1961 to extend spaceflight capability in support of Apollo.
Kennedy's goal was accomplished on the Apollo 11 mission when astronauts Neil Armstrong and Buzz Aldrin landed their Apollo Lunar Module (LM) on July 20, 1969, and walked on the lunar surface, while Michael Collins remained in lunar orbit in the command and service module (CSM), and all three landed safely on Earth on July 24. Five subsequent Apollo missions also landed astronauts on the Moon, the last in December 1972. In these six spaceflights, twelve men walked on the Moon.
Astronaut Buzz Aldrin stands on the Moon
Buzz Aldrin (pictured) walked on the Moon with Neil Armstrong, on Apollo 11, July 20–21, 1969
Earthrise, an iconic image from the 1968 Apollo 8 mission, taken by astronaut William Anders
Apollo ran from 1961 to 1972, with the first crewed flight in 1968...
http://scitech.quickfound.net/astro/project_apollo.html
To begin with, most engineers felt that any scheme involving rendezvous was too complicated and risky; therefore they preferred "direct ascent" plans which would required at least a Saturn C-8 (with a 12 million pounds thrust 1st stage, 8 F-1 engines) or an even larger "Nova" class launch vehicle.
After President Kennedy made his "before this decade is out" speech, it gradually became obvious that the enormous rocket required to accomplish a direct ascent mission could not possibly be available in time. So the majority of engineers changed their preference to an Earth Orbit Rendezvous (EOR) plan. This would have used two or more launch vehicles (probably Saturn Vs). One would launch the spacecraft, and the other carry fuel which would be transferred to the craft in Earth orbit. Or the spacecraft and fuel might be launched in segments which would be joined together in Earth orbit
Both direct ascent and EOR presented difficulties in spacecraft design:
1. For one vehicle to make the trip, land on the moon, return to Earth, and a portion of it reenter the Earth's atmosphere would have required a far larger spacecraft than the eventual Apollo CSM and LM combined. The fuel for the return to Earth, and the reentry capsule, would have to be carried to the lunar surface and back up to orbit. This much larger, heavier spacecraft would be far more difficult to land on the moon than a smaller, lighter one would be.
2. The shape of such a dual-purpose craft was troublesome. Pilots need to see where they are going. How could a single craft be designed which would allow the pilots to look down at the lunar surface, while allowing them to recline facing upward during ascent to Earth orbit and, later, while reentering the Earth's atmosphere? Solutions were suggested, but none were satisfactory.
Enchanted Rendezvous: John C. Houbolt and... Lunar Orbit Rendezvous..., Monograph 4 (1995) http://history.nasa.gov/monograph4.pdf
Remarks by Wernher von Braun about Mode Selection for the Lunar Landing Program, 7 June 1962 http://www.hq.nasa.gov/office/pao/History/Apollomon/apollo6.pdf