The Chicxulub crater is an impact crater buried underneath the Mexican
Yucatán Peninsula, with its center located offshore, near the town of
Chicxulub. The crater is about 180 kilometers (110 mi) in diameter,
making it one of the largest confirmed impact structures in the world;
the asteroid whose impact (animation shown) formed the crater was at
least 10 km (6 mi) in diameter. Discovered by geophysicists looking
for petroleum in the late 1970s, the impact structure was formed around
66 million years ago near the end of the Cretaceous period. It is
widely accepted that the devastation and climate disruption from the
impact was the cause of the Cretaceous–Paleogene extinction event, in
which around 75 percent of all plant and animal species on Earth became
extinct, including all non-avian dinosaurs. A 2021 study stated that the
impactor likely originated in the outer main part of the asteroid belt.
Read more: <https://en.wikipedia.org/wiki/Chicxulub_crater>
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Today's selected anniversaries:
1777:
American Revolutionary War: Fort Clinton and Fort Montgomery
were captured by British forces under Sir Henry Clinton, dismantling the
Hudson River Chains.
<https://en.wikipedia.org/wiki/Battle_of_Forts_Clinton_and_Montgomery>
1908:
Austria-Hungary announced the annexation of Bosnia and
Herzegovina, causing a crisis that permanently damaged the country's
relations with the Russian Empire and the Kingdom of Serbia.
<https://en.wikipedia.org/wiki/Bosnian_Crisis>
1973:
Egyptian forces crossed the Suez Canal to launch an attack on
the fortified Israeli Bar Lev Line, starting the Yom Kippur War.
<https://en.wikipedia.org/wiki/Operation_Badr_%281973%29>
1989:
About 200 members of the San Francisco Police Department
instigated a police riot in the Castro following a peaceful protest held
by ACT UP.
<https://en.wikipedia.org/wiki/Castro_Sweep>
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Wiktionary's word of the day:
subliminal:
1. (physiology) Of a stimulus: below the limen or threshold of conscious
perception, especially if still able to produce a response; also
(generally), below the threshold where a response can be produced.
2. (psychology) Without directed awareness or thought; subconscious
(dated), unconscious.
3. (by extension) Of an advertisement, a message, etc.: conveyed in a
manner that a person is unaware of being influenced by it.
4. (physiology) Chiefly preceded by the: something which is below the
limen or threshold of conscious perception.
5. (psychology) Chiefly preceded by the: the subconscious (dated) or
unconscious self.
6. (by extension) An advertisement, a message, etc., which is conveyed
in a manner that a person is unaware of being influenced by it.
<https://en.wiktionary.org/wiki/subliminal>
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Wikiquote quote of the day:
Beware of assumptions that seem 'obvious' in one decade. They may
become quaint in the next.
--David Brin
<https://en.wikiquote.org/wiki/David_Brin>
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