Oxygen is a chemical element with symbol O and atomic number 8. A
member of the chalcogen group on the periodic table, it is a highly
reactive nonmetal and oxidizing agent that forms oxides with most
elements as well as other compounds. By mass, oxygen is the most
abundant element in the Earth's crust and the third-most abundant in the
universe, after hydrogen and helium. Two atoms of the element can bind
to form dioxygen, a colorless and odorless gas that constitutes 20.8% of
the Earth's atmosphere, produced by photosynthesis from water and carbon
dioxide. Oxygen is present in water, proteins, nucleic acids,
carbohydrates, and fats. Its name was coined in 1777 by Antoine
Lavoisier, whose experiments helped to discredit the then-popular
phlogiston theory of combustion and corrosion. Common uses of oxygen
include residential heating, internal combustion engines, production of
steel, plastics and textiles, brazing, welding and cutting of steels and
other metals, rocket propellant, oxygen therapy, and life support
systems in aircraft, submarines, spaceflight and diving.
Read more: <https://en.wikipedia.org/wiki/Oxygen>
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Today's selected anniversaries:
917:
Liu Yan declared himself emperor, establishing the Southern Han
state in southern China, at his capital of Panyu (present-day
Guangzhou).
<https://en.wikipedia.org/wiki/Liu_Yan_(emperor)>
1781:
American Revolutionary War: French naval forces handed Britain
a major strategic defeat in the Battle of the Chesapeake.
<https://en.wikipedia.org/wiki/Battle_of_the_Chesapeake>
1882:
A group of London school boys led by Bobby Buckle founded
Tottenham Hotspur F.C. so they could continue to play sports during the
winter months.
<https://en.wikipedia.org/wiki/Tottenham_Hotspur_F.C.>
1921:
Popular American comedian Roscoe "Fatty" Arbuckle attended a
party during which a woman was fatally injured; although he was
eventually acquitted of manslaughter, the trial's scandal derailed his
career.
<https://en.wikipedia.org/wiki/Roscoe_Arbuckle>
1977:
NASA launched the robotic space probe Voyager 1, currently the
farthest spacecraft from Earth.
<https://en.wikipedia.org/wiki/Voyager_1>
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Wiktionary's word of the day:
skitter:
1. (intransitive) To move hurriedly or as by bouncing or twitching; to
scamper, to scurry.
2. (intransitive) To make a scratching or scuttling noise while, or as if,
skittering.
3. (transitive) To move or pass (something) over a surface quickly so that
it touches only at intervals; to skip, to skite.
<https://en.wiktionary.org/wiki/skitter>
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Wikiquote quote of the day:
The artist should not only paint what he sees before him, but also
what he sees in himself. If, however, he sees nothing within him, then
he should also refrain from painting what he sees before him. Otherwise
his pictures will be like those folding screens behind which one expects
to find only the sick or the dead.
--Caspar David Friedrich
<https://en.wikiquote.org/wiki/Caspar_David_Friedrich>
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