Pure

The Moon

The Moon is Earth's only natural satellite. It orbits around Earth at an average distance of 384,400 km (238,900 mi), or about 30 times Earth's diameter, having a sidereal period of 27.3 days and a synodic period of 29.5 days. The Moon faces Earth always with its near side by having a rotation period that equals its orbital period, resulting from being tidally locked to Earth. Its gravitational influence is the main driver of Earth's tides and causes Earth's day to lengthen very slowly. Its diameter is 3,474 km (2,159 mi), which is roughly one-quarter that of Earth or twice the width of Australia, making it by far the largest and most massive satellite in the Solar System in relation to its parent planet and the fifth-largest Solar System satellite overall. T… more »