The sun and moon do not have this effect of backwards or retrograde motion, but the other planets all go through phases of retrograde motion, as viewed from the earth. In astronomical reality, the planets do continue to move in the same direction, anticlockwise around the sun.
Mercury and Venus, the only two planets which orbit the sun inside the earth's own orbit, are retrograde when they appear to be in front of the sun from a geocentric perspective (Their motion is direct when they are behind the sun.) Although Mercury and Venus appear to move faster than the sun, by turning retrograde periodically, they always stay within one or two signs of the sun. Mars, Jupiter, Saturn, Uranus, Neptune and Pluto, whose orbits all lie outside the earth's own orbit, appear to turn retrograde during periods in which the earth is moving more quickly than they are. This occurs when they form an opposition to the sun.
In ephemerides planets in retrograde motion have an "R" printed next to them.
Before a planet changes its direction from either retrograde to direct or vice versa its motion becomes increasingly slower until it appears to come to a stop. This is called the stationary phase.
The planets have different periods of retrograde motion:
- Mercury 3 times a year for 3 weeks,
- Venus roughly every 18 months for 40 to 44 days,
- Mars roughly every 26 months for 60 to 80 days,
- Jupiter roughly every 13 months for about 4 months,
- Saturn roughly every 12 1/2 months for about 4 1/2 months,
- Uranus roughly every 12 months for about 5 months,
- Neptune roughly every 12 months for 5 months and 6 days,
- Pluto roughly every 12 months for 5 to 6 months.
Uranus, Neptune and Pluto are retrograde for nearly half the year. They are very common in horoscopes, to the point where they probably need no special interpretation, as so many people have them.
The core meaning of a retrograde planet is that its basic energies are turned inward. A retrograde planet can therefore be beneficial in encouraging people with natal retrogrades to be introspective. At the same time, the person may find it difficult to express the retrograde planet's basic nature in an outward, straightforward way. For example, a person with natal Mercury retrograde may become a deep thinker, while simultaneously having difficulty in expressing his ideas in a logical fashion. Saturn can show where and how a person feels inadequate or frustrated, but with Saturn opposite the sun, Saturn will be retrograde, heightening self-esteem issues, as Saturn's natural critical proclivities are turned inward.
A retrograde planet can turn direct, or a direct planet can turn retrograde by secondary progression. The retrograde Mercury or Venus in a natal chart will usually turn direct at some time during the course of a person's life, making it easier to express their energies in a direct manner.
A retrograde planet in the natal chart has already passed over its natal position before the birth took place. For this reason retrograde planets can indicate something that a person may feel familiar with without having a rational explanation for it.
When transiting planets turn retrograde they pass over certain degrees of the zodiac a second time; or in some cases up to four times as they move back and forth. Such transits indicate a deepening of the theme indicated by the nature of the transiting planet, its sign, houses, and aspects to other planets.
Retrograde planets also have meaning in Predictive Astrology. Mercury retrograde has a bad reputation for times when communications and transportation go awry. Some astrologers caution against signing contracts during these periods. Mars rules surgeons, so some prefer to avoid surgery when Mars is retrograde. In horary astrology, a retrograde planet is usually considered to be weakened. However, sometimes a retrograde significator can indicate a person who is turning back or revisiting an earlier decision, perhaps due to regrets or second thoughts.
- Visualizing Retrograde Motion of Planets (Video David Cochrane, 2015)
- Synodic Cycles and Planetary Retrogrades (Nick Fiorenza, 2013)
- Mercury cycle data 2000-2099
- Venus cycle data 2000-2099
- Mars cycle data 2000-2099
- Jupiter cycle data 1600-2099
- Saturn cycle data 1600-2099
- Uranus cycle data 1600-2099
- Neptun cycle data 1600-2099
- Pluto cycle data 1600-2099
- Chiron cycle data 1600-2099
- Further ephemeris
- Peay, Pythia, 2004. Mercury Retrograde: Its Myth and Meaning, Jeremy P. Tarcher/Penguin.
- Sullivan, Erin, 2000. Retrograde Planets: Traversing the Inner Landscape, Samuel Weiser, Inc.
- Detailed and substantial volume.