This Day In History

Pioneer 10 launched to Jupiter


Pioneer 10, the world’s first outer-planetary probe, is launched from Cape Canaveral, Florida, on a mission to Jupiter, the solar system’s largest planet. In December 1973, after successfully negotiating the asteroid belt and a distance of 620 million miles, Pioneer 10 reached Jupiter and sent back to Earth the first close-up images of the spectacular gas giant. 

In June 1983, the NASA spacecraft left the solar system and the next day radioed back the first scientific data on interstellar space. NASA officially ended the Pioneer 10 project on March 31, 1997, with the spacecraft having traveled a distance of some six billion miles.

Following its encounter with Jupiter, Pioneer 10 explored the outer regions of the solar system, studying energetic particles from the sun (solar wind), and cosmic rays entering our portion of the Milky Way. The spacecraft continued to make valuable scientific investigations in the outer regions of the solar system until its science mission ended on March 31, 1997. Principal investigator Dr James Van Allen of the University of Iowa operated Pioneer 10's Geiger-Tube Telescope instrument.

Headed in the direction of the Taurus constellation, Pioneer 10 will pass within three light years of another star–Ross 246–in the year 34,600 AD Bolted to the probe’s exterior wall is a gold-anodized plaque, 6 by 9 inches in area, that displays a drawing of a human man and woman, a star map marked with the location of the sun, and another map showing the flight path of Pioneer 10. The plaque, intended for intelligent life forms elsewhere in the galaxy, was designed by astronomer Carl Sagan.    —History