Uranus The name of this planet is pronounced `yoor a nus` and not `your anus`! It was discovered in 1781 by British astronomer Sir William Herschel, who originally called it Georgium Sidus (Georgian Planet) after his patron King George III. This name was used in Great Britain for almost 50 years until Uranus, suggested by Johann Bode in Germany, was deemed more suitable for compatibility with the naming of other planets from classical mythology.
Uranus is the third largest planet in the Solar System, after Jupiter and Saturn, and could contain 64 Earths. It is the seventh planet in distance from the Sun, over 19 times the distance of Earth.
At a magnitude of +5.4, Uranus is visible to the naked eye appearing similar to a star. Through a telescope it appears as a faint blue-green disk, the colour resulting from the planet’s atmosphere, consisting of 2% methane found in the upper atmosphere absorbing red light. The remainder of the atmosphere contains 83% hydrogen, 15% helium plus small amounts of acetylene and other hydrocarbons. The core of the planet is thought to be composed of rock and ice, covered by an ocean.
Uranus has an equatorial diameter of 51,800 kilometres (32,190 miles) and a mean distance from the Sun of 2,870,990,000 kilometres (1,782,500,000 miles). Its year, the time taken to orbit the Sun, is equal to 84.01 Earth years. Uranus` day, the time taken to revolve around its axis, is equal to 17 hours 14 minutes Earth time.
At 97.9º, Uranus tilts over so far on its axis that it rotates on its side along its orbital path. Because of this, its poles are sometimes pointed almost directly at the Sun and the planet experiences extreme seasons. There are 21 years of constant daytime and 21 years of constant night-time, interspersed by 21 years of the more usual decreasing and increasing day and night times. A collision with another vast body when the Solar System was forming is thought to have caused Uranus to tilt. Winds up to 600 kilometres per hour blow in its atmosphere and the temperature at the cloud tops is an average of -200ºC.
Uranus has at least eleven rings, first discovered in 1977. The outermost is composed of ice boulders, each measuring several metres across. The inner ring is at 38,000 kilometres from Uranus and the outer is 51,140 kilometres distant. Of Uranus` 27 known moons, Cordelia is the closest at 50,000 kilometres and 2002U2 is the furthest at 21,000,000 kilometres.
The two largest moons, Titania and Oberon, were discovered by Herschel in 1787. Two more, Ariel and Umbriel, were discovered in 1851, Miranda in 1948, a further eleven by Voyager II in 1985 and 1986, and the remainder between 1997 and 2003. Unlike the other bodies in the Solar System, which have been named from classical mythology, Uranus` moons are named after characters from William Shakespeare and Alexander Pope.
Uranus has four moons larger than Miranda but this was the satellite that Voyager II approached closer than any of the others, enabling clear images to be taken. Miranda was named after the daughter of Shakespeare`s magician Prospero in the play The Tempest. This moon has a diameter of 480 kilometres (300 miles) and a chaotic surface unlike any other known object in the Solar System. There are deep canyons, up to 20 kilometres (12 miles), terraced layers, craters, ridges and an assortment of young and old surfaces.
Launched in 1977 NASA’s Voyager II flew past Uranus in January 1986. The spacecraft took 7,000 images of Uranus, its rings and moons.
Uranus was known as the god of the sky. He was the first son of Gaia (the earth) and also became her husband. Their children included the Titans who were six sons (Oceanus, Coeus, Crius, Hyperion, Iapetus and Cronus) and six daughters (Theia, Rhea, Themis, Mnemosyne, Phoebe and Tethys). Numerous other offspring included the Cyclopes (Brontes, Steropes and Arges, who were one eyed giants), the Hecatonchires (Briareus, Cottus and Gyes, who each had one hundred hands and fifty heads) and the Erinyes (spirits of punishment and goddesses of vengeance who avenged family wrongs).
Uranus hated the sight of his monstrous children, the Cyclopes and the Hecatonchires, and was afraid of their mighty strength. He hid them away in Tartarus (the prison within the bowels of the earth for fallen gods) inside Gaia, causing her intense pain. The discomfort was so great that she asked her youngest son, Cronus, to castrate his father, to cease his fertility and put an end to more monstrous offspring. Cronus struck with a sickle as Uranus came to lie with Gaia, and cut off Uranus’ genitals. From the blood that fell from the wound more children were born in the form of nymphs and giants, and when Cronus threw the severed genitals into the sea a white foam appeared and gave birth to Aphrodite the goddess of love and desire.
In a different version of the story the blood, which fell from the mutilation, gave birth to the Erinyes (Furies), the Giants and the Meliae (Nymphs of manna ash trees) and, when Cronus threw the sickle into the sea, the island of Corfu home of the Phoenicians, sprang up.
After Uranus had been emasculated, the sky separated from Gaia and Cronus became king of the gods. Later, Zeus (the son of Cronus) deposed his father and became the supreme god of the Greek Pantheon.
In terms of astrology, Uranus is the planet of change and original thinking. Expressed in its positive form, Uranus endows a person with inspiration, serendipity, resourcefulness, originality and sometimes genius or psychic power. In its negative form, Uranus’ influence results in abnormal and aberrant behaviour, moodiness, an inability to follow through with plans or achieve personal goals and sometimes even perversion.