Animation showing the orbit of the Moon around Earth, and how it moves to produce a supermoon. A supermoon is a full Moon that appears larger than normal in the sky, as it occurs with the Moon near its perigee (closest point to Earth, red dot). The Moon's orbit around Earth is an ellipse. At the start of the animation, the full Moon occurs with the Moon at apogee, the most distant point from Earth in its orbit (cyan dot). This means the Moon appears relatively small in the sky (inset, upper left). The Moon's orbit around the Earth itself rotates around the Earth, however, and when the full Moon is at perigee a super full Moon is seen. The Moon's orbit takes 3233 days to rotate around Earth. However, supermoons occur every 412 days (every 14th full Moon), as the Earth is also rotating around the Sun. See clip K006/7165 for a demonstration of this cycle.