The atmosphere of Jupiter is the largest planetary atmosphere in the
Solar System. It is primarily made of molecular hydrogen and helium in
roughly solar proportions; other chemical compounds are present only in
small amounts, and include methane, ammonia, hydrogen sulfide and
water. The latter one has not been directly observed but is thought to
reside deep in the atmosphere. The oxygen, nitrogen, sulfur and noble
gas abundances in Jupiter's atmosphere exceed solar values by a factor
of about three. The atmosphere of Jupiter lacks a clear lower boundary
and gradually transitions into the fluid interior of the planet. From
lowest to highest, the atmospheric layers are the troposphere,
stratosphere, thermosphere and exosphere. Each layer has characteristic
temperature gradients. The lowest layer, the troposphere, has a
complicated system of clouds and hazes, comprising layers of ammonia,
ammonium hydrosulfide and water. The upper ammonia clouds visible at
Jupiter's surface are organized in a dozen zonal bands parallel to the
equator and are bounded by powerful zonal atmospheric flows (winds)
known as jets. The bands alternate in color: the dark bands are called
belts, while light ones are called zones. Zones, which are colder than
belts, correspond to upwellings, while belts mark descending air. The
zones' lighter color is believed to result from ammonia ice; what gives
the belts their darker colors is not known with certainty. The Jovian
atmosphere shows a wide range of active phenomena, including band
instabilities, vortices (cyclones and anticyclones), storms and
lightning.
Read the rest of this article:
<http://en.wikipedia.org/wiki/Atmosphere_of_Jupiter>
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Today's selected anniversaries:
1537:
The Honourable Artillery Company, currently the oldest surviving
regiment in the British Army, was formed by Royal Charter from King
Henry VIII.
<http://en.wikipedia.org/wiki/Honourable_Artillery_Company>
1609:
Italian astronomer Galileo Galilei demonstrated his first telescope, a
device that became known as a terrestrial or spyglass refracting
telescope, to Venetian lawmakers.
<http://en.wikipedia.org/wiki/Galileo_Galilei>
1835:
The New York Sun perpetrated the Great Moon Hoax, publishing articles
about the supposed discovery of life on the Moon.
<http://en.wikipedia.org/wiki/Great_Moon_Hoax>
1920:
Polish forces under Józef Piłsudski successfully forced the Russians to
withdraw from Warsaw at the Battle of Warsaw, the decisive battle of
the Polish–Soviet War.
<http://en.wikipedia.org/wiki/Battle_of_Warsaw_%281920%29>
1945:
About ten days after World War II ended with Japan announcing its
surrender, armed supporters of the Communist Party of China killed
Baptist missionary John Birch.
<http://en.wikipedia.org/wiki/John_Birch_%28missionary%29>
1989:
Eight years after it made its closest approach to Saturn, the Voyager 2
spacecraft reached Neptune, the last planet visited before leaving the
solar system.
<http://en.wikipedia.org/wiki/Voyager_2>
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Wiktionary's word of the day:
moot (adj):
1. (Commonwealth) Subject to discussion; unsolved or impossible to
solve.
2. (North America) Having no impact or relevance
<http://en.wiktionary.org/wiki/moot>
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Wikiquote quote of the day:
Against boredom even gods struggle in vain.
--Friedrich Nietzsche
<http://en.wikiquote.org/wiki/Friedrich_Nietzsche>