Saturn
Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter. It is a gas giant with an average radius of about nine and a half times that of Earth. It only has one-eighth the average density of Earth; however, with its larger volume, Saturn is over 95 times more massive.
The Romans named the seventh day of the week Saturday, Sāturni diēs ("Saturn's Day"), for the planet Saturn.
Observation
Saturn has been known since prehistoric times, and in early recorded history it was a major character in various mythologies. Babylonian astronomers systematically observed and recorded the movements of Saturn. In ancient Greek, the planet was known as Φαίνων Phainon, and in Roman times it was known as the "star of Saturn".
Mythology
In ancient Hebrew, Saturn is called Shabbathai. Its angel is Cassiel. Its intelligence or beneficial spirit is 'Agȋȇl (Hebrew: אגיאל, romanized: ʿAgyal), and its darker spirit (demon) is Zȃzȇl (Hebrew: זאזל, romanized: Zazl). Zazel has been described as a great angel, invoked in Solomonic magic, who is "effective in love conjurations". In Ottoman Turkish, Urdu and Malay, the name of Zazel is 'Zuhal', derived from the Arabic language (Arabic: زحل, romanized: Zuhal).
In ancient Roman mythology, the planet Phainon was sacred to this agricultural god, from which the planet takes its modern name. The Romans considered the god Saturnus the equivalent of the Greek god Cronus; in modern Greek, the planet retains the name Cronus—Κρόνος: Kronos.
Saturn is named after the Roman god of wealth and agriculture and father of Jupiter. Its astronomical symbol (♄) has been traced back to the Greek Oxyrhynchus Papyri, where it can be seen to be a Greek kappa-rho with a horizontal stroke, as an abbreviation for Κρονος (Cronus), the Greek name for the planet. It later came to look like a lower-case Greek eta, with the cross added at the top in the 16th century to Christianize this pagan symbol.
The Roman festival of Saturnalia was named for the god Saturn.
Astrology
In astrology, Saturn represents the traits: industrious, melancholic, and tranquil.
Saturn rules over Capricorn and Aquarius. Western astrology appraises Saturn as the primary native ruler of the tenth house. In traditional Hindu astrology however, Saturn ruled both the first and eighth houses, and had its joy in the twelfth house of mischief and bad luck.
Dante Alighieri associated Saturn with the liberal art of astronomia (astronomy and astrology).
In Chinese astrology, Saturn is ruled by the element earth, which is warm, generous, and co-operative. In Indian astrology, Saturn is called Shani or "Sani", representing a noteworthy career and longevity. He is also the bringer of obstacles and hardship.
According to Heinrich Cornelius Agrippa, chalcedony is a stone under the planets Saturn and Mercury.