1967 – Surveyor 3 landed on the moon and began sending photos back to the U.S. April 17 – 20th

Surveyor 3 on Moon.jpg

Launched on April 17, 1967, Surveyor 3 landed on April 20, 1967, at the Mare Cognitum portion of the Oceanus Procellarum (S3° 01′ 41.43″ W23° 27′ 29.55″), in a small crater that was subsequently named Surveyor. It transmitted 6,315 TV images to the Earth.[citation needed]

As Surveyor 3 was landing (in a crater, as it turned out [1][2]), highly reflective rocks confused the spacecraft’s lunar descent radar. The engines failed to cut off at 14 feet (4.3 meters) in altitude as called for in the mission plans, and this delay caused the lander to bounce on the lunar surface twice.[3] Its first bounce reached the altitude of about 35 feet (10 meters). The second bounce reached a height of about 11 feet (3.4 metres). On the third impact with the surface—from the initial altitude of 3 meters, and velocity of zero, which was below the planned altitude of 14 feet (4.3 meters), and very slowly descending —Surveyor 3 settled down to a soft landing as intended.

This Surveyor mission was the first one that carried a surface-soil sampling-scoop, which can be seen on its extendable arm in the pictures. This mechanism was mounted on an electric-motor-driven arm and was used to dig four trenches in the lunar soil. These trenches were up to seven inches (18 centimeters) deep. Samples of soil from the trenches were placed in front of the Surveyor’s television cameras to be photographed and the pictures radioed back to the Earth. When the first lunar nightfall came on 3 May 1967, Surveyor 3 was shut down because its solar panels were no longer producing electricity. At the next lunar dawn (after 14 terrestrial days, or about 336 hours), Surveyor 3 could not be reactivated, because of the extremely cold temperatures that it had experienced. This is in contrast with the Surveyor 1, which was able to be reactivated twice after lunar nights, but then never again.[citation needed]

Surveyor 3 became famous after the manned mission Apollo 12 used it as a landing target site. Landing within walking distance on 19 November 1969, the crew took several pictures of the probe and removed some pieces which were returned to Earth. Surveyor 3 is the only probe visited by humans on another world.