Event:
Mariner 2 launched to Venus; flyby mission
More Notable Events on July 27:
1996 Bomb explodes at Atlanta Olympic Park, 1 killed, 110 injured
1986 Greg Lemond is 1st American to win Tour de France
1949 1st jet-propelled airline, De Havilland Comet, flies
1947 Yogi Berri starts record 148 game errorless streak
1940 Billboard magazine starts publishing bestseller charts
