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The moon orbits the earth in a little under 28 earth days. It travels at almost 2,290 miles per hour. Coincidentally, the moon's rotation period is also a little under 28 days, meaning the same face points toward the earth during its entire orbit.
Best Answer: The Moon has phases because it orbits Earth, which causes the portion we see illuminated to change. The Moon takes 27.3 days to orbit Earth, but the lunar phase cycle (from new Moon to new Moon) is 29.5 days.The Moon spends the extra 2.2 days catching up because Earth travels about 45 million miles around the Sun during the time the Moon completes one orbit around Earth. Re-worded it a little.ne solar day = 24 hours, and 29.53 solar days is the synodic month. You are correct in saying it takes 27.3 solar days for the moon to orbit the earth-that's the sidereal month. But in addition to the moon orbiting the earth, the earth-moon system is orbiting the sun. That's why the sidereal and synodic months differ.