Every few hundred years, Jupiter and Saturn meet in a Great Conjunction. For medieval Muslim astrologers the cycles would represent the rise and fall of empires, the coming of messiahs, and foretell the apocalypse.

The next conjunction is December 20th 2020.

A thread-

Jupiter and Saturn are the two slowest classical wandering stars of astrology. Many civilizations from the Babylonians to the Greeks associated them with world-changing events.

But it would be the Persian Sassanians who would use their movements as unique time-periods.

According to scholars like Pingree, the idea was picked up by medieval astrologers of the Islamic world like Ma’shallah, Abu Mas’shar, Ibn Hibinta, Al Qabisi and others.

In this theory the whole of creation was born on the first conjunction in Aries and from there cycled through a recognizable pattern:

Every 20 years Jupiter and Saturn would meet in a zodiac sign within one elemental triplicity

Every 200ish years Jupiter and Saturn would move from one elemental triplicity to another

Every 900ish years the cycle would begin again

While the movement of the two planets are often treated as transits, they also fall into another category; that of planetary periods alongside fardars and dawr.

These planetary periods formed the basis of a theory of history in medieval thought.

According to astrologers like Mashallah all of world history was shaped by these planetary periods and their cycles signified momentous events

Abu Ma’shar for example claimed the Great Flood happened during a conjunction in Cancer while Christ was born during a conjunction in Sagittarius.

Even the rise of Islam was mapped out onto this framework.

Mashallah and Abu Ma’shar both noted the birth of Muhammad and Islam under the auspices of the Great Conjunction in Scorpio.

The Great conjunction in Aquarius, like the one this month, came to represent the collapse and fragmenting of the caliphate and was linked to the coming of the Mongols with several predictions from the time period raising alarms.

Reflecting the deep anxieties of a turbulent world, astrologers warned the Great Conjunction in Aquarius would foretell:

-the fall and rise of dawla (dynasties)
-old and corrupt rulers
-corruption of the wind (plague)

-turbulent transitions
-the coming of false messiahs
-righteous religions
-violence in Iraq, Iran, and Shams
-violence in the streets
-Uprisings
-danger for swamplands (like DC)
-Miraculous events

The Great conjunction was used as a planetary period technique alongside more specialized methods to draw out precise predictions including 2 other conjunctions, eclipses, comets, special calculations known as lots, and symbolic progression of planets and the ascendant.

The theory of Jupiter and Saturn conjunctions was adopted by European astrologers who translated the writings of the medieval Muslims.

Jewish astrologers like Ibn Ezra commented extensively on the methods of Mashallah, who was also Jewish.

In the 14th century Levi Ben Gerson used the technique in his prediction about the Black Plague.

Meanwhile Jupiter-Saturn conjunction in Aquarius was claimed as the auspicious sign of the rise of Timur i lang and an omen of his death.

Jupiter-Saturn conjunctions became one of the more significant contributions to historical astrology and modern astrologers who talk about the great transits of the outer planets are often working in the modern descendent of an older theory.

In 2020, the Jupiter-Saturn conjunction in Aquarius marks the beginning of the Air period (though technically we had its first taste in Libra in 1980). They will continue to conjunct in air signs for a period of 240 years

So ends the cycle of earth and so begin the cycle of air.

And while a thousand years has passed from the era of the medieval astrologer, their anxieties still resonate with our apocalyptic fears and utopian hopes.

For historians of science and religion, the Jupiter-Saturn conjunctions are a fascinating topic revealing the truly unique synthesis of knowledge: of Hellenic horoscopic astrology, ancient Babylonian astral omens, Persian planetary periods, and Indic calculations.

If you’re interested in a breakdown of the actual techniques and the chart of the great conjunction of 2020, I’ve shared a detailed post on patreon: https://www.patreon.com/posts/44583047 

I'll share more on astrology from in the Islamic world and related ideas of the Great Conjunction in future threads