1775: André-Marie Ampère, after whom the unit of current is named, was born. 1901: Zénobe-Théophile Gramme, inventor of the Gramme dynamo, died. 1930: Apollo 11 lunar lander astronaut Edwin "Buzz" Aldrin was born. 1960: The U.S. Army promoted Elvis Presley to the rank of Sergeant. 1969: Astronomers at the University of Arizona documented the first optical identification of a pulsar. 1981: Iran released 52 Americans that had been held hostage for 444 days, just minutes after the U.S. presidency had transferred from Jimmy Carter to Ronald Reagan. 1986: Britain and France announced plans to build the Chunnel  - rail tunnels underneath the English Channel. 2004: The Salvation Army announced it had received a $1.5B donation from the estate of Joan Kroc, widow of McDonald's founder Ray Kroc.