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
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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)
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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)