The Cat's Eye Nebula is a planetary nebula in the constellation of Draco. Structurally, it is one of the most complex nebulae known, with high resolution Hubble Space Telescope observations revealing remarkable structures such as knots, jets and sinewy arc-like features. It was discovered by William Herschel on February 15, 1786, and was the first planetary nebula whose spectrum was investigated, by the English amateur astronomer William Huggins in 1864. Modern studies reveal several mysteries. The intricacy of the structure may be caused in part by material ejected from a binary central star, but as yet there is no direct evidence that the central star has a companion. Also, measurements of chemical abundances reveal a large discrepancy between two measurement methods, the cause of which is uncertain.
Read the rest of this article: http://en.wikipedia.org/wiki/Cat%27s_Eye_Nebula
_______________________________ Today's selected anniversaries:
1215: King John of England put his seal to the Magna Carta. (http://en.wikipedia.org/wiki/Magna_Carta)
1389: In the Battle of Kosovo, Turks defeated Serbs and Bosnians. (http://en.wikipedia.org/wiki/Battle_of_Kosovo)
1752: Benjamin Franklin conducted an experiment to prove that lightning is electricity by flying a kite in a thunderstorm. (http://en.wikipedia.org/wiki/Benjamin_Franklin)
1904: The General Slocum burned in New York's East River, over 1,000 died. (http://en.wikipedia.org/wiki/General_Slocum)
1954: The Union of European Football Associations was founded in Basel, Switzerland. (http://en.wikipedia.org/wiki/UEFA)
_____________________ Wikiquote of the day:
"If fate means you to lose, give him a good fight anyhow." -- William McFee (http://en.wikiquote.org/wiki/William_McFee)
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