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Click here to read about RF CafeKirt Blattenberger
BSEE
KB3UON
EIEIO

Carpe Diem!
(Seize the Day!)

5th MOB:
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Equine Kingdom:
My daughter Sally's horse riding website

Day in Engineering History Archive - December 21
December 21

Winter Solstice.  Please click here to visit RF Cafe  Happy Hanukkah!  Please click here to visit RF Cafe.

1807: Joseph Fourier's memoir "On the Propagation of Heat in Solid Bodies," was read to the Paris Institute, and contained what we now call Fourier series, which he had worked upon since around 1804. 1878: Jan Łukasiewicz, who invented Reverse Polish Notation (RPN), was born. 1898: Scientists Pierre and Marie Curie discovered the radioactive element radium. 1929: My father, "Arthur Blattenberger, was born. 1968: Apollo 8, the first manned voyage to the moon, was launched. 1988: A Libyan terrorist's bomb exploded aboard Pan Am Flight 103, a Boeing 747, over Lockerbie, Scotland, killing 270 people. 1990: American aeronautical engineer Kelly Johnson, who founded the Lockheed Skunk Works, died. 2012: The Long Count of the Mayan calendar will cycle.

| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |

Note: These historical tidbits have been collected from various sources, mostly on the Internet. As detailed in this article, there is a lot of wrong information that is repeated hundreds of times because most websites do not validate with authoritative sources. On RF Cafe, events with hyperlinks have been verified.
Please submit significant historical events and dates for inclusion in these lists. I will be glad to include your name and birthday. Please do not submit your death date ;-) A couple years ago, I began commemorating the birthdays of notable people and events with special RF Cafe logos. Where available, I like to use images from postage stamps from the country where the person or event occurred.

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Webmaster:  Kirt Blattenberger, BSEE - KB3UON
Family Websites:  Airplanes and Rockets | Equine Kingdom

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