The JUICE spacecraft continues its journey to Jupiter. On September 28, it will fly past our planet and perform a gravity-assist maneuver in Earth’s gravitational field. This will allow it to gain the required speed while also saving the fuel needed to enter orbit.
JUICE Flyby
As www.media.inaf.it reports, the JUICE spacecraft will return to Earth on September 28. It is designed to study Jupiter and, in particular, its icy moons. However, to reach them, it needs to gain speed with the help of gravity-assist maneuvers.
JUICE was launched into space aboard the French Ariane 5 launch vehicle back in April 2023. Scientists have high hopes for the mission in the search for evidence of oceans beneath the ice of Europa and Ganymede, so the spacecraft is very heavy because it carries a large amount of equipment, including radar. For this reason, even if there were enough fuel onboard for a direct flight to the gas giant, there would not be enough left to slow down afterward and enter orbit around it.
To solve this problem, engineers selected a different route — around the Sun, with two close approaches to Earth. The first took place in 2024, when the spacecraft had to slow down. This was done so that it could later encounter Venus and gain significant speed in its gravitational field. Now it must gain the remaining speed during its second and third maneuvers near Earth.
How the Maneuver Will Take Place
On August 17, JUICE carried out a series of small maneuvers to ensure that it would pass our planet at a precisely determined distance. On September 28, it will be 8,640 km from Earth. This is much farther away than the ISS and most satellites, but closer than the Moon. At this point, it will fire its engine and gain additional speed with the help of Earth’s gravity.
During the maneuver, which is scheduled to take place next week, the spacecraft will adjust its trajectory by approximately 20° and gain an additional 3.5 km/s of speed. However, even this will not be enough. JUICE will complete another orbit around the Sun and once again approach our planet for a third gravity-assist maneuver. That maneuver will finally place it on a trajectory toward Jupiter.
JUICE is expected to reach the largest planet in the Solar System in July 2031. It will slow down near Jupiter and orbit the planet for some time, and then in 2034 it will reduce its speed even further. The spacecraft will enter orbit around the largest moon in the Solar System — Ganymede — and begin its detailed study.
