Free Astronomy Magazine May-June 2019

27 MAY-JUNE 2019 ASTRONAUTICS Sun returned, but it did so every morning for the rest of the year. Having succeeded in the first at- tempt, there was bewilderment when, in September 1966, Surveyor 2 was lost due to a correction of its trajectory around the Moon. In April 1967, Surveyor 3 landed in a crater 220 meters in diameter in Oceanus Procellarum, bouncing small trenches, to inspect the near subsurface, and to roll rocks to de- termine the degree of selectivity of their erosion. Unlike its predeces- sor, Surveyor 3 survived only one lunar night. More unlucky was Sur- veyor 4, for which contact was lost several minutes before landing. After sampling two western seas and failing to reach a site on the several times before stopping. The inner wall appeared covered with small craters, one of which had dug large blocks of rock, indicating that the regolith on the surface was not many meters thick. In ad- dition to a camera, this lander had an arm equipped with a shovel to investigate the mechanical proper- ties of the surface material, to dig A POLLO 12 − Right and below, ALSEP (Apollo Lunar Surface Experiments Package) removal from the lunar module. [NASA, Project Apollo Archive]