The first experiments set up on the Moon. The Apollo 11 astronauts Buzz Aldrin and Neil Armstrong deployed the EASEP from the lunar module equipment bay on 20 July 1969. It consisted of a passive seismometer experiment (PSE) and a lunar ranging retroreflector (LRRR, known as ‘LR cubed’). The latter provided a means for astronomers on Earth to measure the distance between their telescopes and the LRRR.
Subjects: Astronomy and Astrophysics.