Ganymede is a moon of Jupiter and the largest moon in the Solar System.
Completing an orbit in roughly seven days, it is the seventh moon and
third Galilean moon from Jupiter. Ganymede participates in a 1:2:4
orbital resonance with the moons Europa and Io, respectively. It is
larger in diameter than the planet Mercury but has only about half its
mass. It has the highest mass of all planetary satellites with 2.01
times the mass of the Earth's moon. It is composed primarily of
silicate rock and water ice, and a saltwater ocean is believed to exist
nearly 200 km below Ganymede's surface. Ganymede is the only satellite
in the Solar System known to possess a magnetosphere, likely created
through convection within the liquid iron core. The satellite has a
thin oxygen atmosphere that includes O, O2, and possibly O3. Ganymede's
discovery is credited to Galileo Galilei, who observed it in 1610. The
satellite's name was soon suggested by astronomer Simon Marius, for the
mythological Ganymede, cupbearer of the Greek gods and Zeus's beloved.
Read the rest of this article:
<http://en.wikipedia.org/wiki/Ganymede_%28moon%29>
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Today's selected anniversaries:
532:
The Nika riots began in Constantinople, resulting in nearly half the
city being burned or destroyed and tens of thousands of people being
killed.
<http://en.wikipedia.org/wiki/Nika_riots>
1842:
When he reached the safety of a garrison in Jalalabad, Afghanistan,
William Brydon, an assistant surgeon in the British Army during the
First Anglo-Afghan War, became the sole European survivor of a party of
over 4,500 military personnel and over 10,000 civilian camp followers
retreating from Kabul, excluding a few prisoners released later.
<http://en.wikipedia.org/wiki/William_Brydon>
1898:
The Paris newspaper L'Aurore published "J'accuse...!", an open letter
by French writer Émile Zola to French President Félix Faure exposing
the Dreyfus affair.
<http://en.wikipedia.org/wiki/J%27accuse_%28letter%29>
1968:
American singer Johnny Cash recorded his landmark album At Folsom
Prison live at the Folsom State Prison in Folsom, California.
<http://en.wikipedia.org/wiki/At_Folsom_Prison>
1991:
The January Events: Soviet troops attacked Lithuanian independence
supporters at the TV Tower in Vilnius, killing 14 people.
<http://en.wikipedia.org/wiki/January_Events>
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Wiktionary's word of the day:
go the extra mile (v):
(idiomatic) To make an extra effort; to do a particularly good job
<http://en.wiktionary.org/wiki/go_the_extra_mile>
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Wikiquote quote of the day:
All religions speak about death during this life on earth. Death must
come before rebirth. But what must die? False confidence in one’s own
knowledge, self-love and egoism. Our egoism must be broken.
--G. I. Gurdjieff
<http://en.wikiquote.org/wiki/G._I._Gurdjieff>
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