View from space, looking down on Earth’s North Pole
From here, the Moon orbits counterclockwise.
View from Earth’s Northern Hemisphere
The Moon in the sky, with north at the top
The near side
From the Southern Hemisphere, the Moon looks upside down, so the lit side is on the opposite side.
The red dot and flag mark the same spot on the near side. Times are approximate; sizes and distances are not to scale.
Sunlight comes from the left. Both views use the same moment: the top-down view shows where the Moon is, and the sky view shows how much of its sunlit half we can see. One orbit: about 27.3 days. One phase cycle: about 29.5 days. Earth and the Moon also travel around the Sun, so the sunlight direction slowly changes. The darker part is lunar nighttime, not Earth’s shadow.
Learn more about the science
Yes, the Moon really does spin
Rotation means spinning on an axis. Revolution means traveling around another object. The Moon completes one rotation and one revolution around Earth in about 27.3 days. Because these motions take the same amount of time, nearly the same side, called the near side, faces Earth. The far side faces away. If the Moon orbited Earth without rotating, we would see different sides during one orbit.
In real life, our viewing angle changes slightly, letting us see a little around the edges. This apparent wobble is called libration; it is not shown in this simple model.
A full cycle of Moon phases takes about 29.5 days. Earth and the Moon are also traveling around the Sun, so the Moon must move a little farther to reach the same phase again.
Is there a permanently dark side of the Moon?
No whole side stays dark. Both the near side and the far side have day and night. At new moon, sunlight illuminates the far side. At full moon, sunlight illuminates the near side. Compare these two positions:
View from space, looking down on Earth’s North Pole
New moon: sunlight illuminates the far side. The near side faces Earth but receives no direct sunlight.
How do we know what the far side looks like?
In 1959, the Luna 3 spacecraft returned the first photographs of the far side. Spacecraft have since mapped it in detail. In April 2026, Artemis II astronauts also observed and photographed the far side during their lunar flyby. Compare the two sides:
Moon images: NASA
Explore the science: NASA: Moon Facts · NASA: Top Moon Questions · NASA: Moon Craters · NASA: Artemis II Lunar Flyby
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