Among the activities of Apollo astronauts on the Moon were:
- Bringing back to Earth extensive samples of lunar rock and soil. The rocks turned out to be ancient, suggesting no significant change since the surface of the Moon formed, about 4.5 billion years ago. The “soil" (regolith) had probably been pulverized by impacts, but as the “Surveyor" missions showed, it was firm enough to provide support.
- Crews of Apollo 15, 16, and 17 explored the Moon aboard an electrically driven “moon buggy. "
- Extensive video pictures from the Moon were beamed to Earth--even one (by a remotely controlled camera) of the take-off from the Moon by the Apollo 17 crew. Also, the Earth and its “geocorona" of glowing hydrogen were photographed by a special camera using ultraviolet light.
- A seismometer was placed on the Moon, showing that the Moon was seismically much quieter than Earth.
- Metal foils were hung out (like a flag) to receive the solar wind. They were then returned to Earth where the composition of the ions caught in them was analyzed.
- Corner reflectors were placed on the Moon, so that laser beams reflected from them could accurately measure the distance.