saw the first Moon landing and moonwalk by astronauts Neil Armstrong and Buzz Aldrin (astronaut Michael Collins piloted the Command Module in lunar orbit and never walked on the moon).
After the Lunar Module landed in the Sea of Tranquility, Armstrong said, "Houston, Tranquility Base here. The Eagle has landed." Later stepping onto the lunar surface, he said, "That's one small step for [a] man, one giant leap for mankind." According to Chris Kraft, NASA officials chose Armstrong as the first to walk on the Moon because he was more humble than Aldrin, and because he was the Commander. However, the stated reason was that Armstrong's seat was closer to the door. Apollo 11, like other Apollo missions, launched atop a Saturn V booster.
all utilized spacewalks staged from a Space Shuttle.
SM1 corrected Hubble's flawed optics by installing COSTAR (a corrective optics system), while removing the High-Speed Photometer to make room. It also replaced the original Wide Field and Planetary Camera, or WFPC "wiff-pick", with WFPC2, which a camera that had optical correction built in.
SM2 replaced the Goddard High-Resolution Spectrograph (GHRS) and Faint Object Spectrograph (FOS) with improved successors.
SM3A replaced failed gyroscope systems.
SM3B replaced the Faint Object Camera (FOC) with the Advanced Camera for Surveys (ACS), and also repaired NICMOS, which was installed during SM2.
SM4 was originally cancelled after the Columbia Disaster by then-NASA Administrator Sean O'Keefe, but was revived by Michael Griffin, who took over the post in 2005. SM4 installed WFC3 (made from some parts of the original WFPC) and the Cosmic Origins Spectrograph (COS), and conducted other repairs. No further repairs are planned, as much of HST's functionality will be replicated with the James Webb Space Telescope, scheduled for launch in 2018