Telescopes have improved a lot over the past century, but seeing a planet up close from a spaceship is still an unmatched experience. In the late 1970s and early 1980s, missions like Pioneer 10 and Voyager 1 revealed breathtaking views of Jupiter. But it wasn’t until NASA launched the Galileo probe in 1989 that we really began to study the gas giant in depth.
On its journey to Jupiter, Galileo flew by Venus, capturing stunning images of its clouds. When it reached Jupiter in 1995, it made history as the first spacecraft to orbit an outer planet. Galileo’s mission focused on studying Jupiter, its magnetic field, and its moons.
NASA describes the mission’s main goal: “a 23-month tour of the Jovian system, which included multiple close encounters with Jupiter’s major moons.” Although the primary mission ended in December 1997, the spacecraft continued to operate, extending its mission three times. Over its lifetime, Galileo encountered Jupiter’s moons 35 times, providing incredible insights into each one.
The probe discovered remarkable things: intense volcanic activity on Io, evidence of a hidden ocean beneath Europa, and even a magnetic field around Ganymede. Interestingly, during its mission, Galileo became the only spacecraft to witness a comet crashing into Jupiter. This event helped scientists gather more data about the planet’s atmosphere and its composition.
One of Galileo’s most thrilling achievements was when it dropped a probe into Jupiter’s atmosphere in July 1995. The probe plummeted without any fuel, reaching speeds of 170,000 kilometers per hour (about 106,000 miles per hour) and enduring temperatures double that of the Sun’s surface. Though it only transmitted data for under an hour, it provided essential information about Jupiter’s atmosphere, revealing differences in chemical makeup compared to the Sun. This data contributes significantly to understanding how gas giants like Jupiter evolved.
On September 21, 2003, Galileo’s mission came to a strategic end. To protect the icy moon Europa from possible contamination, NASA chose to crash Galileo into Jupiter. It hurtled toward the giant planet at an astonishing 48.2 kilometers per second (almost 108,000 miles per hour). This final act helped safeguard future exploration efforts, specifically for the hunt for extraterrestrial life beneath Europa’s icy crust.
Galileo’s legacy continues to shape our exploration of Jupiter and its moons. Today, missions like the Juno spacecraft build on its findings, offering more insights into why Jupiter is such a unique planet in our solar system.
For more information about the Galileo mission, check out the NASA website.
