<P> Uranus has two astronomical symbols . The first to be proposed, ♅, was suggested by Lalande in 1784 . In a letter to Herschel, Lalande described it as "un globe surmonté par la première lettre de votre nom" ("a globe surmounted by the first letter of your surname"). A later proposal, ⛢, is a hybrid of the symbols for Mars and the Sun because Uranus was the Sky in Greek mythology, which was thought to be dominated by the combined powers of the Sun and Mars . </P> <P> Uranus is called by a variety of translations in other languages . In Chinese, Japanese, Korean, and Vietnamese, its name is literally translated as the "sky king star" (天王星). In Thai, its official name is Dao Yurenat (ดาว ยูเรนัส), as in English . Its other name in Thai is Dao Maritayu (ดาว มฤตยู, Star of Mṛtyu), after the Sanskrit word for "death", Mrtyu (मृत्यु). In Mongolian, its name is Tengeriin Van (Тэнгэрийн ван), translated as "King of the Sky", reflecting its namesake god's role as the ruler of the heavens . In Hawaiian, its name is Hele'ekala . In Māori, its name is Whērangi . </P> <P> Uranus orbits the Sun once every 84 years . Its average distance from the Sun is roughly 20 AU (3 billion km; 2 billion mi). The difference between its minimum and maximum distance from the Sun is 1.8 AU, larger than that of any other planet, though not as large as that of dwarf planet Pluto . The intensity of sunlight varies inversely with the square of distance, and so on Uranus (at about 20 times the distance from the Sun compared to Earth) it is about 1 / 400 the intensity of light on Earth . Its orbital elements were first calculated in 1783 by Pierre - Simon Laplace . With time, discrepancies began to appear between the predicted and observed orbits, and in 1841, John Couch Adams first proposed that the differences might be due to the gravitational tug of an unseen planet . In 1845, Urbain Le Verrier began his own independent research into Uranus's orbit . On 23 September 1846, Johann Gottfried Galle located a new planet, later named Neptune, at nearly the position predicted by Le Verrier . </P> <P> The rotational period of the interior of Uranus is 17 hours, 14 minutes . As on all the giant planets, its upper atmosphere experiences strong winds in the direction of rotation . At some latitudes, such as about 60 degrees south, visible features of the atmosphere move much faster, making a full rotation in as little as 14 hours . </P>

How many km is uranus away from the sun