Solar System/Moon

The Moon of Earth.

Size

The Moon's diameter is 3476 kilometers, or 0.2764 times that of Earth. This makes the Moon far larger relative to its planet than any other planetary moon in the solar system. In absolute terms it is the fifth largest planetary satellite in the solar system.

Physical characteristics

The surface

The far side of the moon has a vastly different surface then the near side.

Seismology

Recovered lunar basalt.

Origin and evolution

Large impact hypothesis

The large impact hypothesis is a theory that states that the Moon was formed when a Mars sized protoplanet collided with the Earth during the Hadean eon of the Earth, with the debris from the impact accreting into the moon. The named of the mars sized protoplanet is usually given as Theia. It is the most widely accepted hypothesis for the formation of the moon.

The Conquest Of The Moon

Buzz Aldrin on the moon during Apollo 11. Photo taken by Neil Armstrong.