1656: English astronomer Edmond Halley, who discovered the comet that now bears his name, was born. 1881: French aircraft designer Robert Esnault-Pelterie, who developed the concept of ailerons, was born. 1895: Wilhelm Roentgen discovered x-rays ("x" stood for "unknown") during an experiment. 1904: Harvey Hubbell received the first patent for a detachable electric plug/receptacle pair. 1910: William Frost received the first patent for an "electric insect destroyer," aka, a bug zapper. 1918: Lawrence Glendenin, codiscoverer of promethium (Pm, 61), was born. 1942: "Operation Torch," a British-American invasion into French North Africa, commenced. 1978: Classic American painter Norman Rockwell died. 1984: Anna Fisher became the first "mom" to go into orbit onboard the STS-51A flight of the the second flight of the orbiter Discovery.