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Uranus - The "Accidental" Planet

Uranus was the first planet found by telescope. In 1781 William Herschel, a musician by trade but an astronomer by avocation noted a disk shape in Gemini which he assumed was a comet. After carefully plotting its position, he determined it was a planet rather than a comet. Great fame and a permanent appointment as a court astronomer allowed him to pursue astronomy full time. He tried to name the planet after King George his patron. Other names including Herschel were proposed before it was decided that Uranus should be chosen.

It is often said that Herschel found Uranus accidentally but this was disputed by Herschel himself. As he correctly pointed out, he was using the finest telescope in the world, in a systematic survey of the sky when he came upon the seventh planet. He was certain in his own mind that he would have eventually discovered it given his methodical search. As it was the planet had been sighted and noted in star charts no less than 20 times in the prior 90 years. Shortly after discovering Uranus Herschel found Uranus' two largest Moons Oberon and Titania.

Although Uranus waited on the development of the telescope to be found, it is just visible under good conditions. It looks to the eye as one of the very faintest of stars. Usually it can only be spotted by eye if you have a nearby star to use as a stepping stone. The pastel green planet is an easy to spot with small well supported binoculars. You won't see much detail, but even large telescopes see little because the planet has almost no distinguishing marks. It has rings but they are thin strands and all but invisible except when Uranus happens to move between Earth and a star.

Uranus does have one unique characteristic. Its north/south axis is tipped so far that this axis nearly aligns with the orbital path. The other planets have their axis aligned such that their equator and the plane of their orbit are within 30 degrees of each other. How this odd axial alignment of Uranus arose has stimulated many ideas but no positive explanation.

In myth, Uranus was the first husband of Terra [Mother Earth]. Uranus fathered the titans (including Saturn, Pan, Prometheus, Pandora, and Atlas) as well as a race of monsters (Skylla, Charybdis and the Cyclops Polyphemus). As such he was grandfather to the elder gods (Jupiter, Neptune, Pluto) and great grandfather to the junior gods (Mercury, Mars, Venus, Apollo [Sun] and Diana [Moon]). Most Roman gods were renamed from Greek counterparts (Jupiter/Zeus, Mars/Ares, Venus/Aphrodite, and so on) Except for the dropping of an initial "O" the seventh planet has the same name in both cultures.

Few legends surround Uranus. This really wasn't strange because the pantheism of Greece and Rome resulted as the replacement of the deities of earlier peoples by deities of later peoples. Old stories disappeared or were not recorded by the Greek and Roman writers. Uranus as a deity was an odd character indeed. He was less a being that an elemental force. Often he is associated with time or chaos.

Saying where to find Uranus will be easy for the next half dozen years. It will stay in the constellation Aquarius, in a series of pendulum like swings as the Earth circles in its orbit. The center point of these pendulum swings will slowly move from the Capricornus side of Aquarius towards the Pisces side over these half dozen years. Your best bet for finding Uranus is to become familiar with Alpha Aquarii [Sadelmalik]. Once you spot it, Uranus will be a bit below this star on an east west line.

Leslie Coleman
Author:
Leslie Coleman
Entry Date:
May 1, 2002
Published Under:
Leslie Coleman's Columns
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