Day: December 21, 1966

The Soviet Union launches unmanned space probe Luna 13 toward the moon, where it becomes the third space vehicle to successfully make a soft landing on the lunar surface. Larger than its Soviet predecessor, Luna 9, Luna 13 measures the temperature, radiation, and hardness of the moon’s surface, all useful information to have in advance of a manned landing. After operating on the lunar surface for four days, the Luna 13 lander’s batteries are exhausted and the mission is over.