In a few weeks, the JUICE spacecraft will perform the first ever double gravity maneuver. It uses the gravity of the Moon and Earth to take a “shortcut” to Venus. This maneuver will allow JUICE to reach Jupiter.
How to get to Jupiter
The JUICE vehicle was launched in April 2023. The primary targets of its mission are Jupiter’s three icy moons (Europa, Callisto and Ganymede), which have vast oceans of liquid water beneath their surfaces. JUICE is to study these moons and collect data that would help scientists assess their viability.
To complete its tasks, JUICE must enter a permanent orbit around Jupiter. This is not an easy task. JUICE was launched using Europe’s most powerful rocket, Ariane 5 — but it still wasn’t powerful enough to send the spacecraft directly to Jupiter. In addition, in such a scenario, JUICE would have to carry a huge amount of extra fuel with it to slow down enough to enter orbit around Jupiter upon arrival, rather than just whizzing past it and flying off into outer space.
Therefore, the mission specialists decided to use the gravity of other planets. In a series of several maneuvers, JUICE uses it to carefully adjust its trajectory and ensure arrival at Jupiter at the right speed to enter a permanent orbit around it.
Double gravity maneuver
The first of these maneuvers will take place August 19 – 20, 2024. It will be a double maneuver. JUICE will first use the Moon’s gravity and then the Earth’s to slow down and change its trajectory to head towards Venus. At first glance, it seems counterintuitive. But in fact, it is the most efficient way to get to Jupiter. Thanks to the maneuver, JUICE will reach Venus in August 2025. It will then begin to increase its speed. In 2026 and 2029, JUICE will return to Earth twice. The gravity of our planet will give it the necessary speed to enter orbit around Jupiter. JUICE is expected to reach its goal in the summer of 2031.
The success of this entire scheme depends on the upcoming double flyby of the Moon and the Earth. No spacecraft has ever performed such a maneuver before. The slightest mistake in calculations could have catastrophic consequences for the mission.
The flight plan assumes that on August 19, JUICE will fly at a distance of 700 km from the lunar surface. After that, the vehicle will head toward Earth. It will reach it the very next day. The distance of the minimum approach to our planet will be 6807 km. The spacecraft will fly directly over Southeast Asia and the Pacific Ocean and can be seen using binoculars or a telescope.
The upcoming flyby will also give mission specialists a chance to practice. They will activate JUICE’s scientific instruments and make a number of measurements, as well as take photos of the Moon and the Earth. This will give scientists a chance to test the instruments and calibrate them.
According to ESA
