Francium is a chemical element that has the symbol Fr and atomic number 87. It has the lowest known electronegativity and is the second rarest naturally occurring element on Earth (after astatine)<!-- Cf and others occur naturally in supernovae; Universe-wide abundance is difficult to ascertain -->. Francium is a highly radioactive metal that decays into astatine, radium, and radon. As an alkali metal, it has one valence electron. Marguerite Perey discovered francium in 1939. Francium was the last element discovered in nature, rather than synthesized. Outside the laboratory, francium is extremely rare, with trace amounts found in uranium and thorium ores, where the isotope francium-223 is continually formed and continually decays. Perhaps an ounce (30 g) exists at any given time throughout the Earth's crust; the other isotopes are entirely synthetic. The largest amount ever collected of any isotope was a cluster of 10,000 atoms (of francium-210) created as an ultracold gas at Stony Brook in 1996.

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_______________________________ Today's selected anniversaries:

1869: The Cutty Sark, one of the last sailing clippers ever to be built, was launched at Dumbarton in Scotland. (http://en.wikipedia.org/wiki/Cutty_Sark)

1967: The United Nations Security Council unanimously adopted Resolution 242 in the aftermath of the Six-Day War between Israel and Egypt, Jordan, and Syria.

(http://en.wikipedia.org/wiki/United_Nations_Security_Council_Resolution_242)

1975: Two days after the death of Francisco Franco, Juan Carlos was declared King of Spain according to the law of succession promulgated by Franco. (http://en.wikipedia.org/wiki/Juan_Carlos_I_of_Spain)

2005: Angela Merkel assumed office as the first female Chancellor of Germany. (http://en.wikipedia.org/wiki/Angela_Merkel)

_____________________ Wiktionary's Word of the day:

extraneous: Not belonging to, or dependent upon, a thing; not essential or intrinsic; foreign. (http://en.wiktionary.org/wiki/nickel_and_dime)

_____________________ Wikiquote of the day:

This is life to come, — Which martyred men have made more glorious For us who strive to follow. May I reach That purest heaven, — be to other souls The cup of strength in some great agony, Enkindle generous ardor, feed pure love, Beget the smiles that have no cruelty, Be the sweet presence of a good diffused, And in diffusion ever more intense! So shall I join the choir invisible Whose music is the gladness of the world. -- George Eliot (http://en.wikiquote.org/wiki/George_Eliot)