Retrograde Planets and the Sun: Why Planets Turn Where They Do

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Retrograde periods are not scattered at random through the year. Each one happens when a planet, Earth and the Sun reach a particular line-up, so whether a planet is retrograde in a chart is closely tied to how far that planet stands from the Sun. Once you see the pattern, you can often guess from a chart's Sun aspects which planets will carry the R before you look.

This page explains the geometry, separates the retrograde stretch from the stations at its two ends, and shows what follows for Sun aspects. The meaning of the R itself is on what a natal retrograde is, which also covers why the Sun and Moon never carry it.

Calculator and concept: the free birth chart shows each planet's position and its R. It does not show conjunction or opposition phases, stations or distances from the Sun as separate results; those are astronomy discussed here, illustrated with the calculator's own positions.

Two kinds of orbit

"Outer planet" means two different things, so this page avoids the phrase.

• Mercury and Venus orbit the Sun inside Earth's orbit. Astronomers call them the inferior planets.
• Mars, Jupiter, Saturn, Uranus, Neptune and Pluto orbit outside Earth's orbit, as does Chiron. Astronomers call the planets in this group the superior planets.

In astrology, "outer planets" usually means only Uranus, Neptune and Pluto, the slow, generational group covered on outer planets retrograde. Here the dividing line is Earth's orbit, so Mars, Jupiter and Saturn go with Uranus, Neptune and Pluto.

Mercury and Venus: back around the inferior conjunction

Mercury and Venus move faster than Earth. Most of the time we watch them run forward through the zodiac, staying near the Sun. When one of them comes round to pass between Earth and the Sun (the inferior conjunction), it is overtaking Earth on the inside track, and from our moving viewpoint it seems to slide backward against the stars for a few weeks.

When the same planet is on the far side of the Sun (the superior conjunction), it moves forward at its fastest. So a Mercury or Venus conjunct the Sun in a chart can be either retrograde or direct. In a sample of London charts at 12:00 local clock time on every date from 1920 to 2059 (51,135 dates, calculator code version e17516ee):

• Mercury within 8° of the Sun was retrograde on 3,763 of 12,028 dates (31.3%).
• Venus within 8° of the Sun was retrograde on 876 of 6,328 dates (13.8%).

Neither ever got far from the Sun: Mercury at most 27.80° and Venus at most 47.23° in the sample. That is why the only major aspect either can make with the Sun is the conjunction (see Sun conjunct Mercury and Sun conjunct Venus), never a sextile, square, trine or opposition.

Mars to Pluto: back around the opposition

For bodies beyond Earth's orbit the roles swap. Earth moves faster than they do, and once in each cycle Earth overtakes one of them on the inside track. That happens when the body stands opposite the Sun in our sky. Around that opposition the body seems to drift backward, the way a slower car seems to roll back when you pass it.

When the same body is on the far side of the Sun, at its conjunction with the Sun, it moves forward. So for Mars through Pluto, and for Chiron, a conjunction with the Sun always comes with direct motion, and an opposition always comes with retrograde motion.

The stretch and its two stations

The retrograde stretch surrounds the conjunction or opposition, but the stations that start and end it happen well away from that point. They come at a fairly steady angle from the Sun for each planet. Across every calculated station between December 1919 and January 2061:

The angle varies most for bodies whose distance from the Sun varies most: Mercury, Mars and Pluto among the planets, and Chiron, whose very elongated orbit is covered on Chiron retrograde.

Two loops worked through with the calculator's routines, London times:

Mercury reached its conjunction 10 days after turning back and turned forward again 13.6 days after that. Mars took 34 days to reach its opposition and 31 more to turn forward. The middle point does not have to sit exactly halfway, because orbits are ellipses, not circles. The station times are the calculator's model times to the minute; the middle points were found by stepping in 10-minute intervals. Stationary planets at birth covers stations themselves.

What this means for Sun aspects in a chart

Because the stations come at those angles, a planet's major aspect to the Sun often settles whether it is retrograde. In the same noon sample, with the chart's flat orbs (8° for the conjunction, square, trine and opposition, 6° for the sextile):

"Never" and "always" mean in this sample of 51,135 dates. A few edges are worth knowing:

• Mars trine the Sun is never retrograde, because Mars only turns back once it is about 129° or more from the Sun, beyond the trine's 128° limit.
• Jupiter trine the Sun can go either way, because Jupiter's stations come at about 114° to 117°, inside the trine's range.
• Pluto square the Sun was retrograde on 35 of 4,559 dates, in years when Pluto's stations came at less than 98° from the Sun.

So a Sun opposite Saturn or a Sun trine Neptune always arrives with the R on that planet, while a Sun square Mars never does.

Reading the two together

The practical point is not to count the same fact twice. If Saturn opposes the Sun, the R on Saturn is part of that geometry, not a second, independent signal piled on top of the opposition. Read the aspect, then note that the planet was in the retrograde part of its cycle, which some astrologers associate with the planet's themes being worked through more inwardly. That is a common association, not a rule, and it does not turn a chart into a forecast.

For Mercury and Venus, the conjunction is the case to look at. A retrograde Mercury conjunct the Sun was close to its inferior conjunction, passing between Earth and the Sun. A direct one may be near its superior conjunction on the far side. Some astrologers draw a distinction between the two; the chart shows both as a conjunction with or without the R.

Check your own chart

Open your free birth chart, note the Sun's degree, and for each planet from Mercury to Pluto and Chiron work out how far it is from the Sun. Compare with the station angles above: a body well past its station angle should carry the R, one well short of it should not, and a body close to it was born near a station. To see how many R markers charts usually carry, read how common retrograde planets are. For questions about a particular pair, ask the Astrologist.

Related articles

• Mercury Retrograde in the Natal Chart
• Mars Retrograde in the Natal Chart
• Sun Opposite Mars
• Retrograde Planets Without a Birth Time
• Social Planets