Day in Engineering History Archive - June 21

June 21

Happy Birthday to Siméon-Denis Poisson. - Please click here to visit RF Cafe.Summer Solstice.  Please click here to visit RF Cafe1781: Siméon-Denis Poisson, mathematician and experimenter in electromagnetic theory, was born. 1788: The U.S. Constitution went into effect when New Hampshire became the 9th state of ratification. 1874: Anders Ångström, after whom the unit of wavelength is named, died. 1893: The first Ferris wheel premiered at Chicago's Columbian Exposition. 1913: Georgia Broadwick became the first woman to parachute from an airplane. 1945: U.S. troops took the island of Okinawa. 1948: The first successful long-playing microgroove phonograph records were introduced to the public. 1948: The Small-Scale Experimental Machine (SSEM), the first stored-program computer, ran its first program. 1986: Lloyd Espenschied, co-inventor of coaxial cable, died. 2004: Mike Melvill became the first civilian to pilot a craft into space, in Rutan's SpaceShipOne. 2005: The world's first solar sail spacecraft, funded by the non-profit U.S. Planetary Society, was placed in orbit.

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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. Many 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. Images used in the logos are often from open source websites like Wikipedia, and are specifically credited with a hyperlink back to the source where possible. Fair Use laws permit small samples of copyrighted content.