The first lunar surveys were conducted by Soviet Luna probes and American Ranger and Lunar Orbiter spacecraft in the 1960s. The Lunar Orbiter Clementine mapped the lunar surface and found that the lunar crust is thinner on the near side of the moon than the far side. The Lunar Prospector mission discovered that the Moon has a small iron rich core and detected ice water in craters at the lunar poles, estimating up to 3 billion metric tons of water ice may be present.

1. 6 th Grade Science Chapter 9 Sun-Earth-Moon System Notes Section 9.3

4. Russian Luna 16 Luna 16 Moon samples return capsule after touchdown

5. The Ranger project of the 1960s was the first U.S. effort to launch probes directly toward the Moon. The spacecraft were designed to relay pictures and other data as they approached the Moon and finally crash-landed into its surface.

6. Clementine Moon satellite

10. Lunar Prospector