On 17 November 2023, ESA's Jupiter Icy Moons Explorer (Juice) fired its main engine, burning 10% of the mission's entire fuel supply in just 43 minutes.

Why?

The engine burn was part of a two-part manouevre to alter Juice's orbit around the Sun and set it up for its return to Earth in 2024. During this return, Juice will perform the first-ever Lunar-Earth Gravity Assist, swinging by Earth's Moon, before passing Earth 1.5 days later.

The flybys are a crucial part of Juice's journey to Jupiter. During each one, the spacecraft will use the gravity of large bodies to gain the energy it needs without needing to burn much onboard fuel.

But to get the most out of the flybys, Juice must arrive at planet or Moon travelling at exactly the correct velocity and in the correct direction.

Investing this fuel now to line Juice up for next summer's double flyby will pay off for years to come.

Recorded using 'Where is Juice now?'