The Pioneer 10 spacecraft launched #OTD in 1972.
It was a mission of firsts: passing through the asteroid belt, visiting Jupiter, crossing the orbits of Neptune and then Pluto. We detected a last, faint signal on January 23, 2003. Now it belongs to the cosmos.
Images: NASA
Pioneer 10 was also the first human-made object to achieve the escape velocity needed to carry it outside of our solar system. But that won’t happen until the late 2050s, and there won’t be a signal to notify us.
(Despite being first to achieve this escape velocity, Pioneer 10’s trajectory has it leaving the solar system well after the Voyager probes.)
Robert McNees
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