NASA launched the Pioneer 5 space probe from Cape Canaveral Space Force Station.

Although the probe only sent data back to Earth for fifty days, the Pioneer 5 is considered the most successful probe in the Pioneer series. It was originally intended to perform a flyby of Venus, but the window of opportunity was no longer open due to delays. Instead, it was sent to study the interplanetary space between Earth and Venus, where it proved the existence of interplanetary magnetic fields.

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