Prior to the Juno mission, there were several important milestones in our exploration of Jupiter and its atmosphere. Here are some notable historical events and missions:
Pioneer 10 and 11 (1972, 1973): These were the first spacecraft to fly by Jupiter. They provided close-up images and gathered data about Jupiter's atmosphere, magnetic field, and moons.
Voyager 1 and 2 (1979): These spacecraft performed flybys of Jupiter and provided detailed images and data about the planet, its atmosphere, the Great Red Spot, and its moons, including Io and Europa.
Galileo (1989-2003): The Galileo spacecraft was the first to orbit Jupiter. It studied the planet's atmosphere, magnetic field, and moons in great detail. It discovered evidence of subsurface oceans on Jupiter's moon Europa and observed the impact of Comet Shoemaker-Levy 9 with Jupiter in 1994.
Ulysses (1992): Although primarily a mission to study the Sun, the Ulysses spacecraft flew by Jupiter, providing valuable data on the planet's magnetic field and radiation environment.
Cassini (2000): While primarily a mission to Saturn, Cassini performed a flyby of Jupiter in 2000 on its way to Saturn. It captured images and collected data on Jupiter's atmosphere and magnetosphere.
New Horizons (2007): On its way to Pluto, the New Horizons spacecraft flew by Jupiter, using its gravity assist to gain speed. It conducted observations of Jupiter's atmosphere and volcanic activity on its moon Io.
These missions significantly expanded our understanding of Jupiter, its atmosphere, magnetic field, and its moons, paving the way for the Juno mission, which launched in 2011 and continues to provide valuable insights into Jupiter's composition, magnetic field, and deep atmosphere.