NARRATOR: December 2nd, 1973. Tomorrow, Pioneer will make its closest pass of Jupiter, when this fantastic world will fill one-fifth of the sky.
Forty years ago today, Pioneer 10 made history. It became the first spacecraft to fly past Jupiter, the largest planet in the solar system. On December 3rd, 1973, it passed just 81,000 miles above the planet’s colorful cloudtops, gathering a wealth of information about this impressive world.
Despite its great heft, much about Jupiter was still unknown. And its entourage of moons was a complete mystery — no one knew almost anything about them other than their size and mass.
Pioneer 10 was crude by today’s standards. In fact, its pictures weren’t as good as those taken today by Hubble Space Telescope. Yet they provided the first close-up look at the giant planet, and a peek at a few of the moons. Pioneer’s instruments also measured the amount of dust around the planet, the extent of its magnetic field, and the strength of its powerful radiation belts. And as it departed, it showed us something that not even Hubble can reveal, as this NASA documentary recorded:
NARRATOR: Now Pioneer views a sight never before seen by man: the crescent Jupiter. From Earth, we can see only its full phase, like a full Moon. These lighting angles give scientists new information.
As it departed, Pioneer 10 got a gravitational “kick” from Jupiter — making it the first spacecraft to leave the realm of the planets and head toward interstellar space.
Script by Damond Benningfield, Copyright 2013
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