symbol At and atomic number 85. It occurs on Earth as the decay product
of various heavier elements. All its isotopes are short-lived, with
half-lives of 8.1 hours or less. Elemental astatine has never been
viewed because a mass large enough to be seen by the naked eye would be
immediately vaporized by its radioactive heating. The bulk properties of
astatine are not known with any certainty, but they have been predicted
based on its similarity to the other halogens, the lighter elements
directly above it in the periodic table: fluorine, chlorine, bromine and
especially iodine. It is likely to have a dark or lustrous appearance
and may be a semiconductor or possibly a metal; it will probably have a
higher melting point than iodine. Chemically, several anionic species of
astatine are known and most of its compounds resemble those of iodine.
It also shows some metallic behavior, including the ability to form a
stable monatomic cation in aqueous solution (unlike the lighter
halogens).
Read more: <https://en.wikipedia.org/wiki/Astatine>
_______________________________
Today's selected anniversaries:
1658:
Anglo-Spanish War: English colonial forces repelled a Spanish
attack in the largest battle ever fought on Jamaica.
<https://en.wikipedia.org/wiki/Battle_of_Rio_Nuevo>
1910:
The Firebird, the first major work by Russian composer Igor
Stravinsky, made its premiere in Paris.
<https://en.wikipedia.org/wiki/The_Firebird>
1950:
The Korean War began with North Korean forces launching a pre-
dawn raid over the 38th parallel into South Korea.
<https://en.wikipedia.org/wiki/Korean_War>
1975:
Citing threats to national security, Indian Prime Minister
Indira Gandhi unilaterally had a state of emergency declared across the
nation that lasted nearly two years.
<https://en.wikipedia.org/wiki/The_Emergency_(India)>
2013:
Tamim bin Hamad Al Thani became the eighth Emir of Qatar,
currently the world's youngest reigning monarch.
<https://en.wikipedia.org/wiki/Tamim_bin_Hamad_Al_Thani>
_____________________________
Wiktionary's word of the day:
flense:
To strip the blubber or skin from, as from a whale, seal, etc.
<https://en.wiktionary.org/wiki/flense>
___________________________
Wikiquote quote of the day:
I applied my reason at every moment. Reason is excellent for
getting food, clothing and shelter. Reason is the very best tool kit.
Nothing beats reason for keeping tigers away. But be excessively
reasonable and you risk throwing out the universe with the bathwater.
--Yann Martel
<https://en.wikiquote.org/wiki/Yann_Martel>
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