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 seem less drear. For instance, a slight exception may be taken to the statement that the day side of Mercury is always day and the night side always night. As an effect of libration, an oscillatory movement of the planet on its axis, there is a strip of ground on either side, where the dark and light hemispheres meet, upon which the sun rises and shines for 44 days and then sets, leaving it in 44 days of darkness. This strip of ground is 23½ angular degrees in breadth and enjoys a true day, although its "day" is as long as its year, and is equal to 88 of our earth-days.

Mercury, Venus, Mars and Jupiter have been known since antiquity but Uranus was the first planet to be discovered with the aid of a telescope. This planet was discovered in 1781 by William Herschel while mapping stars, and the very fact of its existence astounded the world. Because Galileo had named the satellites of Jupiter the Medician Stars after his patron, Herschel wished to name his newly discovered planet Georgium Sidus, in honor of George the Third. But foreign astronomers would not agree to this and until a name was decided upon, called the planet Herschel. Later, the planet was called Uranus after the most ancient of all the deities, and its sign was the sign of the world hung on the initial of Herschel. ♅ In appreciation of the fact that he had discovered a planet, Herschel was made private astronomer to his king and later knighted.

Uranus is the smallest of the major planets and ranks next to the earth in size, which is the largest of the minor planets, yet there is a great difference in the size of these two planets, for the