The stellia of the four

giant planets

The great gatherings of Jupiter, Saturn, Uranus and Neptune

Our interest in the conjunctions of the giant planets led us to explore the stellia that form when Jupiter, Saturn, Uranus and Neptune meet in the sky.

  • How frequent are the stellia of the giant planets?
  • When have the closest gatherings of Jupiter, Saturn, Uranus and Neptune occurred?
  • What do the charts of those stellia look like?

In this post:

Choosing a pair of conjunctions

We start with the assumption that, for the four planets to form a stellium, their conjunctions should occur very close to each other, both in time and in space. If we can identify certain patterns when multiple conjunctions coincide, then it should help us focus on specific timeframes or portions of the zodiac.

There are six possible conjunctions of the four giant planets, but if we want to choose two conjunctions that cover the four giant planets, we only have three options:

    • (Jupiter-Saturn) and (Uranus-Neptune)
    • (Jupiter-Uranus) and (Saturn-Neptune)
    • (Jupiter-Neptune) and (Saturn-Uranus)

Among those 3 options the first one is particularly significant because it's simply about putting together each giant planet with its "twin brother or sister":

    • Jupiter-Saturn are the conjunctions of the gas giants
    • Uranus-Neptune are the conjunctions of the ice giants

Visualising the conjunctions on a zodiacal wheel

We visualise the timeline of the conjunctions using a polar plot, where the time dimension is represented by the distance of each dot to the center of the circle:

    • the conjunctions of Jupiter and Saturn form a three-armed spiral
    • the conjunctions of Uranus and Neptune form a one-armed spiral
Visualising the timelines of the Jupiter-Saturn conjunctions and the Uranus-Neptune conjunctions since the 6th century BCE until the 21st century, on a tropical zodiacal wheel

We put together the two timelines of the conjunctions of Jupiter-Saturn and Uranus-Neptune, and we found that:

    • during the 6th century BCE, the two spirals overlapped in tropical Taurus.
    • from the 5th century BCE they diverged from each other.
    • from the 3rd century BCE until the 10th century, the two spirals were more than 30 degrees from each other. As an example, the Uranus-Neptune conjunction of 965 was more than 30 degrees apart from the Jupiter-Saturn conjunction of 948.
    • since the 12th century, the Uranus-Neptune conjunctions have occurred less than 30 degrees from the nearest Jupiter-Saturn conjunction

The stellia of the four giant planets in the 12th, 14th and 15th centuries CE

Detailed visualisation of the timelines of the Jupiter-Saturn conjunctions and the Uranus-Neptune conjunctions from 1127 until 2080, on a tropical zodiacal wheel

We looked closer at the last millenium and focused on the closest "encounters" between the Jupiter-Saturn conjunctions and the Uranus-Neptune conjunctions:

    • 1127 & 1136
    • 1305/06 & 1307
    • 1478/79 & 1484

And we found three timeframes when the four giant planets Jupiter, Saturn, Uranus and Neptune formed a stellium:

  • In the 12th century: between the Jupiter-Uranus conjunction of 1126 and the Saturn-Neptune conjunction of 1127.
  • In the early 14th century: between the triple Jupiter-Saturn conjunction of 1305-1306 and the Uranus-Neptune conjunction of 1307.
  • In the late 15th century: between the Jupiter-Saturn conjunction of 1484 and the Jupiter-Uranus conjunction of 1486.

We also found that no stellia of the four giant planets have formed since the 15th century, because the later Uranus-Neptune conjunctions have occurred too many years apart from their nearest Jupiter-Saturn conjunction. As an example, there is a gap of 13 years between the Uranus-Neptune conjunction of 1650 and the Jupiter-Saturn conjunction of 1663. By the time of the 1663 Jupiter-Saturn conjunction at 22 sidereal Scorpio, Neptune was at 22 Sagittarius and Uranus at 18 Capricorn. For the 1821 Uranus-Neptune conjunction that gap is even bigger, as the nearest Jupiter-Saturn conjunction occurred in 1842.

The stellium of 1126-1127 in sidereal Virgo

    • 1124-1125: triple Saturn-Uranus conjunction at 20, 18 and 17 sidereal Leo / 3, 1 and 0 tropical Virgo
    • 1 Sept 1126: Jupiter-Uranus conjunction at 26 sidereal Leo / 9 tropical Virgo
      • Saturn at 7 sidereal Virgo
      • Neptune at 21 sidereal Virgo
      • stellium of the four giant planets within 25 degrees
    • 12 Aug 1127: Jupiter-Saturn conjunction at 16 sidereal Virgo / 29 tropical Virgo
      • Uranus at 0 sidereal Virgo
      • Neptune at 23 sidereal Virgo
      • stellium of the four giant planets within 23 degrees
    • 19 Sept 1127: Jupiter-Neptune conjunction at 24 sidereal Virgo / 6 tropical Libra
      • Uranus at 2 sidereal Virgo
      • Saturn at 20 sidereal Virgo
      • stellium of the four giant planets within 22 degrees
    • Oct 1127: Saturn-Neptune conjunction at 8 tropical Libra
    • Oct 1136: Uranus-Neptune conjunction at 27 tropical Libra

1 Sept 1126 Jupiter-Uranus conjunction; stellium of the four giant planets within 25 degrees

12 Aug 1127: Jupiter-Saturn conjunction; stellium of the four giant planets within 23 degrees

19 Sept 1127: Jupiter-Neptune conjunction; stellium of the four giant planets within 22 degrees

The stellium of 1306-1307 in sidereal Libra

Summary:

    • Dec 1305, Apr 1306 and Jul 1306: triple Jupiter-Saturn conjunction
    • Sept 1306: Jupiter-Uranus conjunction
    • Oct 1306: Jupiter-Neptune conjunction
    • Dec 1306, Apr 1307, Aug 1307: triple Saturn-Uranus conjunction
    • Jan 1307, Mar 1307, Sep 1307: triple Saturn-Neptune conjunction
    • Nov 1307: Uranus-Neptune conjunction

Detailed sequence:

  • 30 December 1305: first Jupiter-Saturn conjunction at 15 sidereal Libra
    • stellium of the four giant planets within 10 degrees
  • 28 April 1306: second Jupiter-Saturn conjunction at 13 sidereal Libra
    • stellium of the four giant planets within 11 degrees
  • 19 July 1306: third Jupiter-Saturn conjunction at 10 sidereal Libra
      • Uranus at 18 sidereal Libra
      • Neptune at 23 sidereal Libra
      • stellium of the four giant planets within 13 degrees
  • 28 September 1306: Jupiter-Uranus conjunction at 21 sidereal Libra
      • Saturn at 16 sidereal Libra
      • Neptune at 24 sidereal Libra
      • stellium of the four giant planets within 9 degrees (probably the second closest alignment)
  • 9 Oct 1306: Jupiter-Neptune conjunction at 24 sidereal Libra
    • Saturn at 18 sidereal Libra
    • Uranus at 21 sidereal Libra
    • stellium of the four giant planets within 7 degrees (probably the closest alignment)
  • 20 December 1306: first Saturn-Uranus conjunction at 25 sidereal Libra
      • Neptune at 27 sidereal Libra
      • Jupiter at 8 sidereal Scorpio
      • Saturn-Uranus-Neptune within 2 degrees
      • stellium of the four giant planets within 13 degrees
  • 16 January 1307: first Saturn-Neptune conjunction
      • Saturn-Uranus-Neptune conjunction within 1 degree
  • 21 March 1307: second Saturn-Neptune conjunction
      • Saturn-Uranus-Neptune conjunction within 1 degree
  • 26 April 1307: second Saturn-Uranus conjunction
      • Saturn-Uranus-Neptune conjunction within 1 degree
  • 25 August 1307: third Saturn-Uranus conjunction at 23 sidereal Libra
      • Neptune at 25 Libra
      • Jupiter at 11 Scorpio
      • stellium of the four giant planets within 18 degrees
      • Saturn-Uranus-Neptune conjunction within 2 degrees
  • 26 September 1307: third Saturn-Neptune conjunction at 26 sidereal Libra
      • Uranus at 25 sidereal Libra
      • Jupiter at 16 Scorpio
      • stellium of the four giant planets within 21 degrees
      • Saturn-Uranus-Neptune conjunction within 1 degree
  • 7 November 1307: Uranus-Neptune conjunction at 27 sidereal Libra
      • Saturn at 0 sidereal Scorpio
      • Jupiter at 24 sidereal Scorpio
      • stellium of the four giant planets within 27 degrees

19 July 1306: third Jupiter-Saturn conjunction; stellium of the four giant planets within 13 degrees

28 Sept 1306: Jupiter-Uranus conjunction; stellium of the four giant planets within 9 degrees

15 Oct 1306: Jupiter-Neptune conjunction; stellium of the four giant planets within 7 degrees (probably the closest alignment)

The stellium of 1484-1486 in sidereal Scorpio & Sagittarius

  • Dec 1478: first Uranus-Neptune conjunction
  • June 1479: second Uranus-Neptune conjunction
  • 25 Aug 1479: third Uranus-Neptune conjunction at 11 sidereal Scorpio / 28 tropical Scorpio
    • Saturn at 1 sidereal Virgo
    • Jupiter at 12 sidereal Gemini
  • 27 Nov 1484: Jupiter-Saturn conjunction at 5 sidereal Scorpio / 23 tropical Scorpio
    • Neptune at 24 sidereal Scorpio
    • Uranus at 5 sidereal Sagittarius
    • stellium of the four giant planets within 30 degrees
  • 5 Nov 1485: Jupiter-Neptune conjunction at 25 sidereal Scorpio / 12 tropical Sagittarius
    • Saturn at 13 sidereal Scorpio
    • Uranus at 8 sidereal Sagittarius
    • stellium of the four giant planets within 25 degrees
  • 25 Jan 1486: Jupiter-Uranus conjunction at 13 sidereal Sagittarius / 0 tropical Capricorn
    • Saturn at 21 sidereal Scorpio
    • Neptune at 28 sidereal Scorpio
    • stellium of the four giant planets within 22 degrees

27 Nov 1484: Jupiter-Saturn conjunction; stellium of the four giant planets within 30 degrees

5 Nov 1485: Jupiter-Neptune conjunction; stellium of the four giant planets within 25 degrees

25 January 1486: Jupiter-Uranus conjunction; stellium of the four giant planets within 22 degrees

The stellia of the four giant planets in the 11th, 10th and 8th centuries BCE

The stellium of 1099-1098 BCE in sidereal Pisces

  • 25 March 1099 BCE: Jupiter-Saturn conjunction at 24 sidereal Aquarius
    • Uranus at 8 Pisces
    • Neptune at 21 Pisces
    • stellium of the four giant planets within 27 degrees
  • 20 January 1098 BCE: Jupiter-Uranus conjunction at 8 sidereal Pisces
    • Saturn at 28 Aquarius
    • Neptune at 21 Pisces
    • stellium of the four giant planets within 23 degrees
  • 25 March 1098 BCE: Jupiter-Neptune conjunction at 23 sidereal Pisces
    • Saturn at 6 Pisces
    • Uranus at 12 Pisces
    • stellium of the four giant planets within 17 degrees
  • 1090-1089 BCE: triple Uranus-Neptune conjunction

The stellium of 920-918 BCE in sidereal Aries

  • February 920 BCE: Jupiter-Saturn conjunction at 16 sidereal Pisces
    • Uranus at 17 sidereal Aries
    • Neptune at 20 Aries
    • stellium of the four giant planets within 34 degrees
  • April 919 BCE: Jupiter-Uranus-Neptune conjunction at 24 sidereal Aries
    • Saturn at 4 Aries
    • stellium of the four giant planets within 21 degrees
  • January 918 BCE: Uranus-Neptune conjunction at 24 sidereal Aries
    • Saturn at 6 Aries
    • Jupiter at 6 Taurus
    • stellium of the four giant planets within 30 degrees
  • April 918 BCE: Saturn-Neptune conjunction at 28 sidereal Aries
    • Uranus at 1 Taurus
    • Jupiter at 17 Gemini

April 919 BCE: Jupiter-Uranus-Neptune conjunction; stellium of the four giant planets in sidereal Aries within 21 degrees

The stellium of 740-739 BCE in sidereal Taurus and Gemini

  • 746 BCE: triple Uranus-Neptune conjunction at 10 sidereal Taurus
  • February 741 BCE: Jupiter-Saturn conjunction at 15 sidereal Aries
  • April 740 BCE: Jupiter-Neptune conjunction at 25 sidereal Taurus
    • Saturn at 4 Taurus
    • Uranus at 9 Gemini
    • stellium of the giant planets within 35 degrees
  • July 740 BCE: Jupiter-Uranus conjunction at 13 sidereal Gemini
    • Saturn at 13 Taurus
    • Neptune at 28 Taurus
    • stellium of the giant planets within 30 degrees
  • February 739 BCE: Jupiter and Uranus direct stations at 13 and 11 sidereal Gemini
    • Saturn at 10 Taurus
    • Neptune at 26 Taurus
    • stellium of the giant planets within 33 degrees

July 740 BCE: stellium of the four giant planets within 30 degrees in sidereal Taurus and Gemini

The stellia of the four giant planets in the 27th, 29th and 31st centuries CE

Given that there is a gap of 1866 years between the stellium of 740 BCE and the stellium of 1127 CE, we speculated that the next stellia could form about 1886 years after the stellia of 1126-1127, 1306-1307 and 1484-1486 CE, which gave a timeframe to "go chasing" for more stellia, near the Uranus-Neptune conjunctions of 3017, 3187 and 3357.

We found that the stellia of the four giant planets will occur earlier than expected:

  • in February 2674: within 32 degrees in sidereal Capricorn, Aquarius and Pisces
  • in April 2853: within 22 degrees in sidereal Pisces and Aries, during a Jupiter-Uranus-Neptune conjunction
  • in April 3032: within 20 degrees in sidereal Aries and Taurus

February 2674: stellium of the four giant planets within 32 degrees in sidereal Capricorn, Aquarius and Pisces

April 2853: stellium of the four giant planets within 22 degrees in sidereal Pisces and Aries

April 3032: stellium of the four giant planets within 20 degrees in sidereal Aries and Taurus