The Artemis program is a Moon exploration program that is led by the United States' NASA and was formally established in 2017 via Space Policy Directive 1. The Artemis program is intended to reestablish a human presence on the Moon for the first time since Apollo 17 in 1972. The program's stated long-term goal is to establish a permanent base on the Moon to facilitate human missions to Mars.

The physical exploration of the Moon began when Luna 2, a space probe launched by the Soviet Union, made a deliberate impact on the surface of the Moon on September 14, 1959. Prior to that the only available means of exploration had been observation from Earth. The invention of the optical telescope brought about the first leap in the quality of lunar observations. Galileo Galilei is generally credited as the first person to use a telescope for astronomical purposes; having made his own telescope in 1609, the mountains and craters on the lunar surface were among his first observations using it.