Uranus is the seventh planet from the Sun and the third largest and fourth most massive planet in the solar system. Uranus was the first planet discovered in modern times. Though it is visible to the naked eye like the five classical planets, it was never recognised as a planet by ancient observers due to its dimness. Sir William Herschel announced its discovery on March 13, 1781, expanding the known boundaries of the solar system. Uranus' atmosphere, while still composed primarily of hydrogen and helium, contains a higher proportion of "ices" such as water, ammonia and methane, along with the usual traces of hydrocarbons. It is the coldest planetary atmosphere in the Solar System, with a minimum temperature of 49 K, and has a complex layered cloud structure, in which water is thought to make up the lowest clouds, while methane makes up the uppermost layer of clouds. Like the other giant planets, Uranus has a ring system, a magnetosphere, and numerous moons. The Uranian system has a unique configuration among the planets because its axis of rotation is tilted sideways, nearly into the plane of its revolution about the Sun; its north and south poles lie where most other planets have their equators. In 1986, images from Voyager 2 showed Uranus as a virtually featureless planet in visible light without the cloud bands or storms associated with the other giants. The wind speeds on Uranus can reach 250 m/s.

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_______________________________ Today's selected anniversaries:

1724: Tumult of Thorn (Toruń): Polish authorities executed the Mayor of Toruń, Royal Prussia and nine other Lutheran citizens following tensions between Protestants and Catholics. (http://en.wikipedia.org/wiki/Tumult_of_Thorn_%28Toru%C5%84%29)

1732: The Royal Opera House opened at Covent Garden in London. (http://en.wikipedia.org/wiki/Royal_Opera_House)

1815: Michel Ney, Marshal of France, was executed by a firing squad near Paris' Jardin du Luxembourg for supporting Napoleon Bonaparte. (http://en.wikipedia.org/wiki/Michel_Ney)

1941: World War II: The Imperial Japanese Navy made its attack on Pearl Harbor, Oahu, Hawaii. (http://en.wikipedia.org/wiki/attack_on_Pearl_Harbor)

1949: Chinese Civil War: The government of the Republic of China relocated from Mainland China to Taipei on the island of Taiwan. (http://en.wikipedia.org/wiki/Taipei)

1988: An earthquake with a moment magnitude of 7.2 struck the Spitak region of Armenia, then part of the Soviet Union, killing at least 50,000 people. (http://en.wikipedia.org/wiki/1988_Spitak_earthquake)

1995: The Galileo spacecraft arrived at Jupiter, a little more than six years after it was launched by Space Shuttle Atlantis during Mission STS-34. (http://en.wikipedia.org/wiki/Galileo_spacecraft)

_____________________ Wiktionary's Word of the day:

matter-of-factly: As though stating a fact. (http://en.wiktionary.org/wiki/matter-of-factly)

_____________________ Wikiquote of the day:

It's an alethiometer. It's one of only six that were ever made. Lyra, I urge you again: keep it private. ... It tells you the truth. As for how to read it, you'll have to learn by yourself. Now go — it's getting lighter... -- The Golden Compass (http://en.wikiquote.org/wiki/Philip_Pullman)