On July 20, 1969, Apollo 11 astronaut Neil Armstrong announced his historic arrival on the ancient lava plain of Mare Tranquillitatis with the following message to NASA: "Houston, Tranquility Base ...

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Moon craters formed when meteorites and asteroids slammed into the lunar surface. Like fossils on Earth, they reveal something about the history of the solar system and how planets were formed. Using ...

Find the locations of the five landing zones considered as the setting for humanity's first steps on another world. When you purchase through links on our site, we may earn an affiliate commission.