Eclipse of the Moon over Earth's horizon, composite image. The blue haze of Earth's atmosphere can be seen above the horizon. The Moon (at upper right) has a diameter just over a quarter of the Earth's. It orbits at a distance of around 385,000 kilometres, taking nearly 30 days for one orbit. It does not have an atmosphere and is a heavily cratered and barren piece of rock that reflects the light of the Sun. This Moon is partially eclipsed, which means it must have moved into the shadow cast by the Earth. Lunar eclipses are visible from anywhere on Earth, where the Moon is above the horizon.