COSMOS JUICE spacecraft makes world-first double Moon-Earth flyby - JUICE

JUICE spacecraft makes world-first double Moon-Earth flyby - JUICE

JUICE spacecraft makes world-first double Moon-Earth flyby

ESA’s JUpiter ICy moons Explorer successfully completed the world’s first-ever double Moon-Earth flyby on 19 and 20 August 2024. Here we briefly present an overview of what happened.

Before JUICE can begin its detailed investigation into the icy moons in 2031, it must undertake a complex, multi-year journey in the Solar System. This will include several planetary flybys to put JUICE on track in its voyage to Jupiter. The double Earth-Moon flyby was a critical part of this journey, serving as a slingshot manoeuvre that will take Juice on a shortcut to Jupiter via Venus.

This double flyby not only represents a first in space navigation but also a major success for the mission team.

On 19 August 2024, JUICE approached the Moon at an altitude of just 750 km and a speed of 4.2 km/s. Images and data at different wavelengths of our natural satellite have shown that JUICE’s remote sensing instruments and navigation cameras are performing very well. The spacecraft’s plasma instruments acquired unique data on the lunar environment. Its radar used this unique opportunity during cruise to acquire an echo reflected from a solid surface, as the other flybys will take place at larger distances. These measurements will allow the team to prepare well the processing algorithms needed for future data analysis.

After the Moon flyby, JUICE proceeded to the second stage: a close pass by Earth one day later at an altitude of just 6840 km, passing over the Pacific Ocean at a speed of 8.4 km/s. Again, images and data taken demonstrate the great performances of JUICE’s payload. In particular, its imaging spectrometer detected molecules within Earth’s atmosphere, an excellent test of its capabilities. Its submillimetre wave instrument measured water, oxygen and ozone, a first in this wavelength range. Its radio and plasma wave instrument was able to detect many different radio emission sources, from Earth as well as from the Sun, gathering an important dataset to train for future Jupiter data. Juice also acquired data on Earth’s radiation belt with unprecedented accuracy.

Images from the JUICE monitoring cameras were released immediately through ESA’s Planetary Science Archive (PSA). Scientific results are expected to be published in 2026, and all data will be available through the PSA in 2029, except for data from the radiation monitor, which is foreseen to be accessible by the end of 2025.

From the navigation point of view, the Moon-Earth flyby went perfectly. Only two small spacecraft manoeuvres were needed to correct JUICE’s trajectory. A significant amount of propellant was saved that will be used later around Jupiter and Ganymede to improve the science return of the mission.

Farewell images, acquired on 9 September 2024 at around 6 million km from Earth, can be found here. [ESA - Juice snaps an Earth–Moon portrait]

After this big challenge, JUICE continues its journey toward Jupiter. The next encounter will be Venus in August 2025.

By Olivier Witasse & Emma Vellard
Edited on the 12th of March 2025

Links to web releases

NASA’s Instruments Capture Sharpest Image of Earth’s Radiation Belt - NASA Science

ESA - Juice's flight through Earth's radiation belts

JUICE : la Terre et la Lune dans les yeux de MAJIS | CNES

JUICE: Earth and Moon through MAJIS eyes | CNES

JUICE: A look at our blue planet

ESA - Juice’s lunar-Earth flyby: the movie

ESA - Listen to Juice’s flyby of Earth

ESA - Juice confirms that Earth is habitable