Retrograde motion is the apparent reversal of a planet’s direction against the zodiac as observed from Earth. It results from relative orbital motion; a planet does not physically reverse its orbit. Astrologers distinguish a retrograde natal planet from a moving planet entering a retrograde period.
Why retrogrades occur
For Mercury and Venus, retrogrades occur in their geocentric cycles around solar conjunctions. Mars and the outer planets show retrograde loops around particular alignments involving Earth and the Sun. The dates of stations—when apparent motion becomes very slow—can be emphasized in astrological calendars. Retrogrades must be calculated, not guessed from an annual schedule.
Reading retrogrades symbolically
Traditional and modern schools interpret retrogradation in different ways. Some emphasize revision, delay or inward reconsideration; others examine planetary condition and visibility. A Mercury retrograde does not automatically cause a broken device or failed contract. The chart house, natal contacts and concurrent transits help establish interpretive context.
Retrograde transits and shadow periods
A planet may cross the same degree three times: once direct, once retrograde and once direct again. Some astrologers include pre- and post-retrograde shadow periods as an extended window. Identify the exact dates and degrees before attaching meaning to the cycle.
Return to Transits & Predictive Astrology for the larger framework of forecasting methods, or read the Astrology encyclopedia for natal fundamentals.