ESA’s Juice probe to Jupiter prepares for first Earth+Moon slingshot fly-by

Graphic showing Juice’s upcoming duel fly-by.
Click for original image.
The European Space Agency’s (ESA) first mission to Jupiter, dubbed Juice (Jupiter Icy Moons Explorer) is about to do the first ever back-to-back fly-bys of the Moon and then the Earth immediately afterward in order to slingshot it forward on its long journey to the gas giant.
The graphic to the right, cropped and reduced to post here, shows the plan. Juice will first fly past the Moon, shifting its path slightly, and then zip past the Earth one day later, its trajectory then under-going a much larger change.
The lunar-Earth flyby will see Juice pass just 700 km [435 miles] from the Moon’s surface at 23:16 CEST on 19 August and 6807 km [4230 miles] from Earth’s surface almost exactly 24 hours later at 23:57 CEST on 20 August.
Using the gravity of the Moon to slightly bend Juice’s trajectory first will improve the effectiveness of the much larger gravity assist at Earth. However, the dual flyby requires extraordinarily precise navigation and timing, as even minor deviations could send Juice in the wrong direction.
The engineering teams have already been doing simulations to make sure they get this complex maneuver right. If all goes right, the spacecraft will then do flybys of Venus in August 2025, Earth in September 2026, and Earth again in January 2029, arriving in Jupiter orbit in July 2031.
Graphic showing Juice’s upcoming duel fly-by.
Click for original image.
The European Space Agency’s (ESA) first mission to Jupiter, dubbed Juice (Jupiter Icy Moons Explorer) is about to do the first ever back-to-back fly-bys of the Moon and then the Earth immediately afterward in order to slingshot it forward on its long journey to the gas giant.
The graphic to the right, cropped and reduced to post here, shows the plan. Juice will first fly past the Moon, shifting its path slightly, and then zip past the Earth one day later, its trajectory then under-going a much larger change.
The lunar-Earth flyby will see Juice pass just 700 km [435 miles] from the Moon’s surface at 23:16 CEST on 19 August and 6807 km [4230 miles] from Earth’s surface almost exactly 24 hours later at 23:57 CEST on 20 August.
Using the gravity of the Moon to slightly bend Juice’s trajectory first will improve the effectiveness of the much larger gravity assist at Earth. However, the dual flyby requires extraordinarily precise navigation and timing, as even minor deviations could send Juice in the wrong direction.
The engineering teams have already been doing simulations to make sure they get this complex maneuver right. If all goes right, the spacecraft will then do flybys of Venus in August 2025, Earth in September 2026, and Earth again in January 2029, arriving in Jupiter orbit in July 2031.