The Oort cloud (artist's rendering pictured) is a hypothesized
spherical cloud of comets that may lie nearly a light-year from the
Sun. It is thought to comprise two separate regions: a spherical outer
Oort cloud and a disc-shaped inner Oort cloud, or Hills cloud; the
outer extent of the cloud defines the boundary of the Solar System.
Objects in the Oort cloud are largely composed of ices, such as water,
ammonia, and methane and are thought to have formed close to the Sun,
later being scattered into space by the gravitational effects of the
giant planets early in the Solar System's evolution. Although no
confirmed direct observations of the Oort cloud have been made,
astronomers believe that it is the source of all long-period and
Halley-type comets entering the inner Solar System, as well as many of
the Centaurs and Jupiter-family comets.
Read the rest of this article:
<http://en.wikipedia.org/wiki/Oort_cloud>
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Today's selected anniversaries:
1786:
Michel-Gabriel Paccard and Jacques Balmat completed the first recorded
ascent of Mont Blanc in the Alps, an act considered to be the birth of
modern mountaineering.
<http://en.wikipedia.org/wiki/Mont_Blanc>
1918:
The Battle of Amiens began in Amiens, France, marking the start of the
Allied Powers' Hundred Days Offensive through the German front lines
that ultimately led to the end of World War I.
<http://en.wikipedia.org/wiki/Battle_of_Amiens_%281918%29>
1929:
German airship LZ 127 Graf Zeppelin embarked on a flight to
circumnavigate the world.
<http://en.wikipedia.org/wiki/LZ_127_Graf_Zeppelin>
1967:
Indonesia, Malaysia, the Philippines, Singapore and Thailand founded
the Association of Southeast Asian Nations.
<http://en.wikipedia.org/wiki/ASEAN>
1988:
The 8888 Uprising, a series of marches, demonstrations, protests, and
riots against the one-party state of the Burma Socialist Programme
Party in Burma, began.
<http://en.wikipedia.org/wiki/8888_Uprising>
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Wiktionary's word of the day:
obesogenic (adj):
That causes obesity
<http://en.wiktionary.org/wiki/obesogenic>
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Wikiquote quote of the day:
No live organism can continue for long to exist sanely under conditions
of absolute reality; even larks and katydids are supposed, by some, to
dream.
--Shirley Jackson
<http://en.wikiquote.org/wiki/Shirley_Jackson>
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