The European Space Agency’s (ESA) Juice spacecraft has completed a unique flight from the Moon to Earth. It used Earth’s gravity to guide it toward Venus and accelerated toward Jupiter.
JUICE made its closest approach to the Moon on August 20 at 2:45 am (IST). This process set it up to make its closest approach to Earth a day later, on August 21 at 3:26 am (IST).
During his flight just 6,840km over Southeast Asia and the Pacific Ocean, Juice used most of his instruments to take pictures and collect scientific data.
The purpose of this flyby was to adjust JUICE’s travel using the gravitational force of the Moon and Earth. Initially, the Moon’s gravity increased JUICE’s speed, causing it to move toward Earth.
Then, Earth’s gravity slowed the spacecraft, causing it to turn toward Venus. This maneuver altered JUICE’s path by 100 degrees from its original path.
The spacecraft’s flyby, despite being risky, was carried out with great precision, saving about 100-150 kg of fuel. Before the flyby, operators made small adjustments to ensure the correct path, constantly monitoring the spacecraft from August 17-22.
Launching in April 2023 left JUICE with extra fuel, allowing it to get closer than previously expected to Jupiter’s moon Ganymede. The successful flyby secured this additional scientific opportunity.
“Thanks to very precise navigation by ESA’s Flight Dynamics team, we managed to use only a small fraction of the propellant we had reserved for this flyby. This will allow us to increase the margin for rainy days or to continue the science mission once we reach Jupiter,” said Ignacio Tanco, spacecraft operations manager for the mission.
Mission Venus and Jupiter
The spacecraft is set to rendezvous with Venus in August 2025. This rendezvous with Venus will lead the spacecraft back toward Earth for additional flybys in September 2026 and January 2029, providing the speed needed to ultimately reach Jupiter by July 2031.
