← Encyclopedia of Astrology · lesson 106/235
Inferior conjunction
An inferior conjunction is the meeting of Mercury or Venus with the Sun when the planet lies between Earth and the Sun. On the chart it looks like any other conjunction: the planet and the Sun share the same degree. In the sky the planet is as close to us as it ever comes, is lost in the Sun's glare, and is moving retrograde. deVore's definition is the plain one: the conjunction is inferior "when the planet is between the Earth and the Sun".
Only Mercury and Venus can do this, because only they orbit inside Earth's path. They are the "inferior" planets in the old astronomical sense — lower, nearer the Sun — not lesser ones.
What happens in the sky
Mercury and Venus never stray far from the Sun: Mercury no more than about 28°, Venus about 47°. They swing out to one side of it and back again, and each swing passes the Sun twice — once on the near side (the inferior conjunction) and once on the far side (the superior conjunction).
- At the inferior conjunction the planet is mid-retrograde: it turns back at its station, meets the Sun halfway through the backward stretch, then stations direct.
- It changes its appearance. Before it, the planet was an evening star, setting after the Sun; after it, it reappears as a morning star, rising before dawn.
- It usually passes a little above or below the Sun, because its orbit is tilted. Only rarely does it cross the Sun's face — a transit. Mercury transits come about thirteen times a century (the next is on 13 November 2032); Venus transits come in pairs more than a century apart (2004 and 2012; the next in December 2117).
| Mercury | Venus | |
|---|---|---|
| Inferior conjunctions | about three a year | every 19 months or so |
| Distance at the time | roughly 0.6 AU | roughly 0.27 AU |
Venus's inferior conjunctions trace a famous figure: five in a row, spread over eight years, fall at five points of the zodiac that join into a near-perfect five-pointed star, slowly creeping backwards round the circle.
How it is read
Modern astrologers who follow planetary cycles treat the inferior conjunction as the planet's new moon — the seed moment of a fresh cycle, as the Sun–Moon conjunction is for the lunation cycle. Michael Meyer and others read the Venus cycle in this way: the inferior conjunction opens a period in which values and affections are reconsidered from the inside, under the retrograde, before Venus emerges as the morning star and carries them forward. A Mercury inferior conjunction is often read as the heart of its retrograde: the point at which the old line of thought is let go and a new one quietly begins.
In a birth chart, someone born near an inferior conjunction has the planet close to the Sun in degree and moving backwards — a placement many read as intensely personal and inward, the planet's themes fused with the sense of self. Dane Rudhyar called a Mercury that rises before the Sun Promethean (looking ahead, impatient to know) and one that sets after it Epimethean (reflecting on what has been); the inferior conjunction is the hinge between the two, as the planet passes from evening to morning.
In the tradition
Older astrologers judged a planet near the Sun by distance more than by side: within about 17 minutes of arc it is cazimi, "in the heart of the Sun"; within a few degrees it is combust; within about 15° it is under the beams. A retrograde Mercury or Venus at inferior conjunction carries both conditions at once, retrograde and combust, which Lilly counted as two debilities. Because the planet seldom passes exactly over the Sun's disc, a true cazimi is rarer at an inferior conjunction than at a superior one. The Hellenistic writers also watched the planet's heliacal rising — its first visible morning appearance a week or two later — as the moment it regained its strength.