The Planets in Astrology: The Classical Gas Giants – Jupiter & Saturn

The classical planets are those visible to the naked eye from Earth. Traditionally this is Mercury, Venus, Mars, Jupiter and Saturn. However, it is little known that, with great eyesight and a dark sky, you can actually see Uranus (faintly) without the aid of a telescope or binoculars. However, it appears classical astronomers either never noticed the faint blue spot, or did not deem it as a planetary object. Thus, Uranus was not officially observed until after the invention of the telescope, when German born British astronomer William Herschel trained his lens on the planet in 1781.

That leaves us with the two biggest classical planets, the king of the Solar System, Jupiter, and the legendarily beautiful ringed world of Saturn. Both are huge gas giants, consisting mostly of hydrogen in various liquid or gaseous states, with a rocky and metallic core. Together they account for 92% of the mass of the Solar System and are some of the brightest objects in our night sky. This has given them real astrological significance, since people first started recording their heavenly mythologies some 30,000 years ago.


Jupiter is 142,000 miles in circumference and is usually the third brightest natural object in Earth’s night sky. Named after the Roman equivalent to Zeus, king of the Gods, Jupiter is the ruling planet of Sagittarius. It takes 11.9 years to complete one revolution around the Zodiac, as viewed from Earth.

In modern western astrology, Jupiter is considered as a sign of fortune, growth, forward movements and protection. For some astrologers, this slips into the territory of gambling and merrymaking. It is the primary ruler of the 9th house, the house of beliefs, but it also associated with the eleventh house – good luck.

Jupiter’s influence is felt strongest on Thursdays. Many romance languages thus derive their name for this day from the gas planet; the French Jeudi and the Spanish Jueves being but two examples.


With its iconic rings, and many moons (62 and counting), Saturn has long been one of the most intriguing planets in the Solar System for both astronomers and astrologers. Saturn is the ruling planet of Capricorn and crosses the ecliptic during its transit of Libra. The planet is named after the Roman God of agriculture, seeds and harvest – something even more important in ancient times than it is today.

Before the discovery of Uranus and Neptune, Saturn was also considered as the ruler of Aquarius as well as Capricorn. Saturn takes 29.5 years to navigate the 12 Zodiacal constellations in its orbit around the Sun. In modern astrology it is associated with order, law, dedication, work ethic, careers and hierarchies. Some astronomers consider it to be slightly mischievous and melancholy, depending on the zodiacal sign it is transiting – which changes every 2.3 years, on average. Saturn, unsurprisingly, is associated with the day Saturday, which was also named after the Roman God.