Planet Conjunctions

A conjunction is the moment two planets meet in the sky, sharing the same place along the zodiac. Pick a pairing below for the upcoming and most recent meetings, how close the two pass, and where to look, all computed live in your browser.

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What a conjunction is

The Sun, Moon and planets all travel along nearly the same line across our sky, the ecliptic. A conjunction happens when two of them arrive at the same point along that line, so they appear close together. They are not close in space, only in direction from Earth; one can be far beyond the other. The closest conjunctions bring the pair within a fraction of a degree, tight enough to fit both in a telescope view, while looser ones pass several degrees apart.

How often a given pair meets depends on their orbits. The fast inner planets catch up to the slow outer ones roughly once a year, while the two slowest bright planets, Jupiter and Saturn, meet only about every twenty years in the famous great conjunction. For the average time between meetings of any pair, see the Synodic-Period Calculator; for the exact dates of any pair, including ones not listed here, use the Planetary Alignment Calculator.

Frequently asked questions

What is a planet conjunction?

A conjunction is the moment two planets arrive at the same point along the ecliptic, the line the Sun, Moon and planets trace across our sky, so they appear close together. The closest pass within a fraction of a degree, while looser ones are a few degrees apart.

Are the two planets actually close together during a conjunction?

No. They only line up in the same direction as seen from Earth; in space one planet can be far beyond the other. A conjunction is a line-of-sight effect, not a real close approach.

How often do two planets meet?

It depends on the pair. A fast inner planet catches up to a slow outer one roughly once a year, while the two slowest bright planets, Jupiter and Saturn, meet only about every twenty years. The Synodic-Period Calculator gives the average for any pair.

What is the great conjunction?

The great conjunction is the meeting of Jupiter and Saturn, which happens only about every 19.86 years, the rarest of the bright-planet pairings. The most recent was in December 2020 and the next is in 2040.