The sixth planet from the sun and the second largest in the solar system, having a sidereal period of revolution about the sun of 29.5 years at a mean distance of about 1.43 billion kilometers (891 million miles), a mean diameter of approximately 121,000 kilometers (75,000 miles), and a mass 96 times that of Earth, The most remote of the anciently known planets, appearing at brightest like a first-magnitude star, (Roman mythology) god of agriculture and vegetation; counterpart of Greek Cronus, proper Roman mythology The god of fertility and agriculture, equivalent to the Greek Kronos, astronomy, astrology The second largest planet in Earth's solar system, famous for its large rings and until recent times the furthest known; represented in astronomy and astrology by ?