Mariner 1

Mariner 1 was the first spacecraft of the American Mariner program, designed for a planetary flyby of Venus. It cost $18.5 million in 1962. It was launched aboard an Atlas-Agena rocket on July 22, 1962. Shortly after takeoff, the rocket responded improperly to commands from the guidance systems on the ground, setting the stage for an apparent software-related guidance system failure.