On Aug. 27, 1962, NASA launched Mariner 2, the world's first successful interplanetary spacecraft. [‘On This Day in Space’ Video Series on Space.com](https://www.space.com/39251-on-this-day-in-space.html)

Mariner 2 flew by Venus after a 3½-month voyage through space. The mission launched just one month after the Mariner 1 mission failed during launch. After departing from Cape Canaveral, Mariner 2 almost met the same fate when an electrical problem with the Atlas-Agena rocket caused it to start rolling, which made it unable to respond to any guidance commands from mission control. By some miracle, the problem fixed itself, and Mariner 2 was on its way to Venus!