Back to Glossary

The Moon

The Moon is Earth’s only natural satellite—a rocky, cratered body about one‑quarter the diameter of Earth, orbiting at an average distance of approximately 384,400 km. It influences tides, stabilizes Earth’s axial tilt, and was formed about 4.5 billion years ago following a collision between Earth and a Mars-sized object.

Source: science.nasa.gov

APODs including "The Moon"

North to the Moon's Pole

22/06/1996

North to the Moon's Pole
Image Credit: NASA Astronomy Picture of the Day

This image is from the voyage of the intrepid Galileo spacecraft as it passed above the Moon's north pole on its long journey to Jupiter. It was made over 60 years after Admiral Byrd became the first to fly over the Earth's north pole. Within a superposed frame of lattitude and longitude lines much of the Moon's familiar face, dominated by smooth dark mare, is brightly lit. Near the pole itself, the harsh shadows reveal a rugged, cratered lunarscape.