IEEE Milestone
Apollo 11 Lunar Laser Ranging Experiment (LURE), 1969
On 1 August 1969, Lick Observatory made the first Earth-to-Moon distance measurement with centimeter accuracy. The researchers fired a gigawatt ruby laser at a retro-reflector array placed on the Moon by Apollo 11 astronauts, and measured the time delay in detecting the reflected pulse. This was the first experiment using a hand-placed extraterrestrial instrument.
August 2019
Submitted by: Eric Goodill