Oberon is the outermost major moon of the planet Uranus. It is the second largest and second most massive of Uranian moons, and the ninth most massive moon in the Solar System. Discovered by William Herschel in 1787, Oberon is named after a character in Shakespeare's A Midsummer Night's Dream. Its orbit lies partially outside Uranus's magnetosphere. Oberon consists of approximately equal amounts of ice and rock, and is likely differentiated into a rocky core and an icy mantle. A layer of liquid water may be present at the core/mantle boundary. The surface of Oberon, which is dark and slightly red in color, appears to have been primarily shaped by asteroid and comet impacts. It is covered by numerous impact craters reaching 210 km in diameter. Oberon possesses a system of canyons (scarps) formed as a result of the expansion of its interior during its early evolution. This moon probably formed from the accretion disk that surrounded Uranus just after the planet's formation. As of 2010, the Uranian system has been studied up close only once: by the spacecraft Voyager 2 in January 1986. It took several images of Oberon, which allowed mapping of about 40% of the moon’s surface.

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_______________________________ Today's selected anniversaries:

1422:

As the only heir to the throne, Henry VI became King of England at the age of eight months following the death of his father Henry V. http://en.wikipedia.org/wiki/Henry_VI_of_England

1888:

Mary Ann Nichols' body was found on the ground in front of a gated stable entrance in Buck's Row, London, allegedly the first victim of the unidentified serial killer known as Jack the Ripper . http://en.wikipedia.org/wiki/Jack_the_Ripper

1907:

The Great Game: Russia and the United Kingdom signed the Anglo-Russian Entente, defining their respective spheres of interest in Persia, Afghanistan, and Tibet. http://en.wikipedia.org/wiki/Anglo-Russian_Entente

1958:

A parcel bomb sent by Ngo Dinh Nhu, younger brother and chief adviser of South Vietnamese President Ngo Dinh Diem, failed to kill Sihanouk of Cambodia. http://en.wikipedia.org/wiki/Ngo_Dinh_Nhu

1986:

After a collision with a freighter, the Soviet ocean liner Admiral Nakhimov sank in the Tsemes Bay area of the Black Sea within seven minutes, killing more than 400 people on board. http://en.wikipedia.org/wiki/SS_Admiral_Nakhimov

1997:

Princess Diana, her companion Dodi Fayed, and their driver Henri Paul were killed in a high speed car accident in the Pont de l'Alma road tunnel in Paris. http://en.wikipedia.org/wiki/Death_of_Diana%2C_Princess_of_Wales

_____________________________ Wiktionary's word of the day:

rhabdomyolysis (n): (medicine) The rapid disintegration of striated muscle tissue accompanied by the excretion of myoglobin in the urine http://en.wiktionary.org/wiki/rhabdomyolysis

___________________________ Wikiquote quote of the day:

There's not a war between Muslims and non-Muslims, but between extremists and moderates of all the religions. ... What is important is not to live in fear. The most dangerous thing to do is to give up and lose hope. The main enemy is not terrorism or extremism, but ignorance. --Queen Rania of Jordan http://en.wikiquote.org/wiki/Queen_Rania_of_Jordan