Observations of the Jovian system began on 6
January 1979 and resulted in the discovery of Jupiter’s
rings, a study of the intensity of the planet’s radiation
belts, and the discovery of the existence of volcanic
activity on Io.
Study of the Jovian system for Voyager 1 concluded
on 13 April 1979, at which point NASA realigned the
probe for its encounter with Saturn in 1980.
By this point, NASA had to decide whether to use
Voyager 1 for a proximity flyby of Saturn’s moon Titan,
and thereby eliminate the probe’s ability to continue
on to the outer-most planet – at the time – Pluto, or to
do a calculated flyby of Sa