moon: Retarded Lunar Motion

Due to the earth's rotation, the moon appears to rise in the east and set in the west, like all other heavenly bodies; however, the moon's own orbital motion carries it eastward against the stars. This apparent motion is much more rapid than the similar motion of the sun. Hence the moon appears to overtake the sun and rises on an average of 50 minutes later each night. There are many variations in this retardation according to latitude and time of year. In much of the Northern Hemisphere, at the autumnal equinox, the harvest moon occurs; moonrise and sunset nearly coincide for several days around full moon. The next succeeding full moon, called the hunter's moon, also shows this coincidence.

Sections in this article:

• Introduction
• Formation and Evolution
• Internal Structure
• Surface Features
• Physical Characteristics
• Tidal Influence of the Moon
• Solar and Lunar Eclipses
• Retarded Lunar Motion
• The Lunar Orbit and Phases
• The Lunar Month
• The Earth-Moon System
• Bibliography

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