The Lunar Surface
Although surface features were observed as early as 1600 by Galileo, most information regarding the surface is from spacecraft exploration.
In 1959 the Soviet Union sent the first spacecraft to orbit the Moon, sending back tantalizing photographs. American astronauts orbited the Moon in 1968 and landed manned expeditions from 1969 to 1972. Six landed during those years, providing copious data from the lunar surface. Apollo experimentation included soil-testing devices, cameras, seismometers, solar wind collectors, and rock collection. The Soviet Union also landed an unmanned craft during this time (1970), collecting additional data for analysis.