The 3 Superior Planets: Saturn, Jupiter, and Mars

Saturn, Jupiter, and Mars follow a similar pattern of motion. Their orbits are completely enclosed within the great annual orbit, revolving in a common center in accordance with the order of the zodiac signs. However, Saturn completes its orbit in thirty years, Jupiter in twelve years, and Mars in twenty-nine months, as though the size of their orbits affects the speed of their revolutions.

If we take the semi-diameter of the great orbit as 25 parts, then:

• The semi-diameter of Mars’ orbit measures 30 parts
• The semi-diameter of Jupiter’s orbit measures 130 parts plus a small fraction
• The semi-diameter of Saturn’s orbit measures 230 parts and one-sixth

(Here, the term “semi-diameter” refers to the distance from the center of the great orbit to the center of the first epicycle.)

Each of these planets has two epicycles, much like the Moon, but following a different law.

• The first epicycle, moving in the opposite direction to the orbit, completes as many revolutions as the orbit itself.
• The second epicycle, opposing the first, doubles the speed of revolution around the planet.

As a result, when the planet is at its farthest distance from the center of its orbit (or at its closest proximity), it remains nearest to the center of its epicycle. However, at the quadrants of its orbit, the planet is at its greatest distance from this center.

Fixed Positions of the Apsides

Due to this complex combination of orbits, epicycles, and revolutions, the greatest elongations and approaches of the planets remain fixed beneath the firmament. This means that their apsides (farthest and closest points in orbit) remain unchanged:

• Saturn’s apsis is located near the star above the shoulder of Sagittarius.
• Jupiter’s apsis is 8 degrees beyond the star marking the end of Leo’s tail.
• Mars’ apsis is 6.5 degrees ahead of the Lion’s heart (Regulus).

Sizes of the Epicycles

The semi-diameters of the epicycles are as follows (relative to a great orbit semi-diameter of 25 parts):

• Saturn:
  • First epicycle: 19 parts, 41 minutes
  • Second epicycle: 6 parts, 34 minutes
• Jupiter:
  • First epicycle: 10 parts, 6 minutes
  • Second epicycle: 3 parts, 22 minutes
• Mars:
  • First epicycle: 5 parts, 34 minutes
  • Second epicycle: 1 part, 51 minutes

The first epicycle is always three times larger than the second.

Primary and Secondary Irregularities in Motion

The primary irregularity is caused by the motion of the epicycles, which create the major variations in the planet’s movement, always within fixed limits beneath the firmament.

However, there is also a secondary irregularity:

• The planets sometimes appear to move backward (retrograde) or pause (stationary motion).
• This effect is not due to the planets themselves, but rather to the Earth’s movement around the great orbit, which alters our line of sight.
• When the Earth moves faster than the planet, it appears to move backward in the sky. This happens when the Earth is closest to the planet, particularly when the planet rises as an evening star.
• Conversely, when the planet sets in the evening or rises in the morning, it appears to move forward again.
• When the Earth’s motion perfectly counteracts the planet’s motion, the planet seems to pause—this typically occurs when the Sun, Earth, and planet form a right triangle.

The extent of this irregularity depends on how close the planet is to the Earth:

• It is smallest for Saturn, larger for Jupiter, and greatest for Mars, based on the proportion of their orbit sizes to that of the great orbit.
• The greatest irregularity occurs when the planet is positioned so that its line of sight touches the circumference of the great orbit.

Latitude Deviations of the Planets

The three superior planets deviate in latitude in a double manner:

• Their epicycles remain in a single plane, yet their orbits tilt away from the ecliptic due to the deflection of their axes.
• Unlike the Moon, their epicycles do not rotate, but always remain aligned with the same region of the sky.
• The nodes (where their orbits intersect the ecliptic) remain fixed in space:
  • Saturn’s ascending node is 8.5 degrees beyond the eastern star in Gemini’s head.
  • Jupiter’s ascending node is 4 degrees before that same star.
  • Mars’ ascending node is 6.5 degrees ahead of the Pleiades (in Taurus).

At these nodes, the planets exhibit no latitude, but their maximum latitudes occur at their quadratures, varying greatly depending on their orbital inclinations.

The maximum inclinations occur when the Earth is closest to the planet (during its evening rise):

• Saturn: 2.67° inclination
• Jupiter: 1.67° inclination
• Mars: 1.17° inclination

Conversely, when the Earth is at its farthest point (during evening setting or morning rising), the inclination is reduced:

• Saturn and Jupiter: reduced by 0.83°
• Mars: reduced by 1.67°

Thus, these latitude variations are most noticeable at their maximum values and gradually decrease as the planet approaches its node.

Effect of Earth’s Motion on Latitude

The Earth’s movement in the great orbit also alters our perception of planetary latitudes:

• Depending on proximity or distance, the angle of visual latitude changes.
• This effect follows mathematical principles, as it is a libration motion occurring along a straight line.

It is possible that the combination of two orbital motions is responsible for this effect:

• If these orbits are concentric, then the lower orbit carries the poles of the upper one, rotating them at double the speed.
• Each orbit’s pole is deflected relative to the pole of the next higher orbit.

Thus, we have described Saturn, Jupiter, and Mars, as well as the orbits surrounding the Earth.