JUICE will use the gravity of Earth and the Moon to slingshot to Jupiter
The European Space Agency’s (ESA) JUpiter Icy Moons Explorer (JUICE) is heading back to Earth – for the time being, anyway. The spacecraft launched from French Guiana on 23 April 2023 and is ultimately bound for Jupiter to study the planet and three of its icy moons: Ganymede, Callisto and Europa. But in order to get there, it needs to perform a series of gravity assists, flying past the planets of the inner Solar System and using their gravitational tides to slingshot itself towards its target – a technique that saves overall fuel.
A 43-minute burn was performed on 17 November as one of two necessary to put JUICE on the right trajectory for the Earth-Moon gravity assist – the first in the series of assists, which will occur in August 2024. “This first burn did 95 per cent of the work, changing JUICE’s velocity by almost 200 metres [656 feet] per second,” said Julia Schwartz, flight dynamics engineer at the ESA’s European Space Operations Centre in Germany. “JUICE is one of the heaviest interplanetary spacecraft ever launched, with a total mass of around 6,000 kilograms, so it took a lot of force and a lot of fuel to achieve this.”
In the coming weeks, the ESA will analyse JUICE’s new orbit before calibrating a second burn to fine tune the probe’s trajectory for the double gravity assist. “If all goes well with both parts of this manoeuvre, we likely won’t need to use the main engine again until we enter orbit around Jupiter in 2031,” Ignacio Tanco, JUICE spacecraft operations manager, said. “For small trajectory corrections between now and then, we will use JUICE’s smaller thrusters.”