[1 ] Saturn [ 2 ] The best of Cassini: High-resolution images of Saturn's rings and moons captured by orbiting spacecraft

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 新竹  Saturn 土星

Ancient observations
See also: Saturn (mythology)

Saturn has been known since prehistoric times.[111] In ancient times, it was the most distant of the five known planets in the Solar System (excluding Earth) and thus a major character in various mythologies. Babylonian astronomers systematically observed and recorded the movements of Saturn.[112] In ancient Roman mythology, the god Saturnus, from which the planet takes its name, was the god of agriculture.[113] The Romans considered Saturnus the equivalent of the Greek god Cronus.[113] The Greeks had made the outermost planet sacred to Cronus,[114] and the Romans followed suit. (In modern Greek, the planet retains its ancient name Cronus—Κρόνος: Kronos.)[115]

The Greek scientist Ptolemy based his calculations of Saturn's orbit on observations he made while it was in opposition.[116] In Hindu astrology, there are nine astrological objects, known as Navagrahas. Saturn is known as "Shani" and judges everyone based on the good and bad deeds performed in life.[113][116] Ancient Chinese and Japanese culture designated the planet Saturn as the "earth star" (土星). This was based on Five Elements which were traditionally used to classify natural elements.[117][118][119]

In ancient Hebrew, Saturn is called 'Shabbathai'.[120] Its angel is Cassiel. Its intelligence or beneficial spirit is Agiel (layga) and its spirit (darker aspect) is Zazel (lzaz). In Ottoman Turkish, Urdu and Malay, its name is 'Zuhal', derived from Arabic زحل. Galileo first saw them in 1610.[122][123] He thought of them as two moons on Saturn's sides.[124][125] It was not until Christiaan Huygens used greater telescopic magnification that this notion was refuted. Huygens discovered Saturn's moon Titan; Giovanni Domenico Cassini later discovered four other moons: Iapetus, Rhea, Tethys and Dione. In 1675, Cassini discovered the gap now known as the Cassini Division.In 1899 William Henry Pickering discovered Phoebe, a highly irregular satellite that does not rotate synchronously with Saturn as the larger moons do.[127] Phoebe was the first such satellite found and it takes more than a year to orbit Saturn in a retrograde orbit.In 1899 William Henry Pickering discovered Phoebe, a highly irregular satellite that does not rotate synchronously with Saturn as the larger moons do.[127] Phoebe was the first such satellite found and it takes more than a year to orbit Saturn in a retrograde orbit.

    The best of Cassini: High-resolution images of Saturn's rings and moons
    captured by orbiting spacecraft
 
                                              
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------------------or the past 13 years, the Cassini spacecraft has been
    orbiting Saturn, capturing high resolution photos of our
    solar system's second-biggest planet, as well as its many moons and
    spectacular rings. As the end of the orbiter's mission approaches,
    it is making a series of dives through the 1,500-mile-wide (2,400km) gap
     between Saturn and its rings before plunging into the planet's surface
     later this year.

      As Cassini prepares for its death dive, IBTimes UK looks back
     at the orbiter's best shots.