Juice, the European Space Agency's Jupiter Icy Moons Explorer, swung past Earth on Monday, 28 September, and filmed its home planet on the way through. ESA's posted a short movie of the flyby on its YouTube channel. It shows Africa, Madagascar and a tiny grey Moon, all shot by the spacecraft's monitoring cameras.

ESA says the flyby went to plan. Earth's gravity bent Juice's path by 20 degrees and added 3.5 kilometres per second to its speed. That's a big step toward Jupiter, and it barely used any fuel.

What the movie shows

ESA's video page walks through the footage frame by frame. In the first few seconds, the view comes from Juice monitoring camera 2, or JMC2, with Earth as a thin crescent at the bottom right. About 10 seconds in, the video switches to JMC1. Nearly the whole disc of Earth sits at the top right, and the big land mass in view is Africa. The Moon shows up as a tiny grey dot to Earth's right. Right at the end, JMC1 gets one last look at Earth in the distance as Juice flies off on 29 September.

Photo: European Space Agency / Wikimedia Commons (CC BY-SA 3.0 IGO), cropped

ESA's caption for one still adds a detail. You can see Madagascar to the right of Africa in a JMC1 frame taken at 13:56 CEST, just after closest approach.

These cameras weren't built for sightseeing. ESA says their real job is keeping an eye on the spacecraft's booms and antennas, especially during the tricky deployments after launch. They take 1,024-by-1,024-pixel snapshots that can be processed in colour, and ESA calls the Earth photos "a bonus". A Swiss company, Micro-Cameras & Space Exploration, built the cameras, and Simeon Schmauß processed the images ESA published.

JMC1 sits on the front of the spacecraft and looks diagonally upward, ESA explains, so its view takes in the deployed antennas and sometimes part of a solar array. That's why bits of Juice itself frame the shots of Earth. ESA has released the stills and the movie under a CC BY-SA 3.0 IGO licence.

The flyby itself

Juice made its closest approach at 13:45 CEST (11:45 UTC) on 28 September, which was 9:15pm in Adelaide. It passed just 8,640 kilometres above the Indian Ocean. ESA says it "skimmed the very outer edge of Earth's atmosphere."

The navigation had to be spot on. ESA set aside six chances to adjust Juice's course in the four weeks before the flyby, and it needed only one tiny nudge. The team's been tracking the spacecraft extra closely since 17 August and will keep it up until 10 October.

"The flyby required ultra-precise navigation in real time. Thanks to our very careful planning, we used only a small amount of the propellant reserved for this flyby," said Angela Dietz, Juice's spacecraft operations manager. "This gives us more to use at Jupiter to carry out observations of the planet's icy moons."

Science on the way past

It wasn't only about steering. ESA says the flyby also gave Juice a third chance to test its science instruments on a real target. The first was the 2024 lunar-Earth flyby, and the second was watching Comet 3I/ATLAS in 2025.

Juice carries 10 science instruments. Teams spent months working out which ones to switch on and when, because power and time on the spacecraft were limited. "Juice's journey to Jupiter provides only a few opportunities to calibrate and validate the instruments under well-understood environmental conditions," said Juice project scientist Claire Vallat, who led that planning. She said some activities had to come first, "for example when Juice was in Earth's shadow this morning, and relying on battery power alone."

ESA points out that an Earth flyby is fairly simple next to what's waiting at Jupiter. It calls this pass a chance to calibrate the instruments, learn how they behave in space, where they "always work a little differently to on Earth", and build the tools to analyse their data.

Juice also spent several days flying through Earth's magnetotail, the part of the planet's magnetic field that streams away from the Sun. At the same time, the European-Chinese Smile mission watched the northern lights and measured magnetic fields and particles closer to Earth. ESA says putting the two sets of data together is a rare chance to link what's going on far out in the tail with what's happening over the poles.

There's more to come. ESA expects to publish images and spectra from some of Juice's instruments in the coming weeks, once the data's down and checked. That includes high-resolution views of the Moon and Earth from JANUS, Juice's main science camera.

The long road to Jupiter

Juice launched on an Ariane 5 from Europe's Spaceport in Kourou, French Guiana, in April 2023. Instead of burning huge amounts of propellant, it's using gravity assists from Earth and Venus to build up enough energy to reach Jupiter. It flew past the Moon and then Earth in August 2024, the first time any spacecraft had used a combined lunar-Earth gravity assist. It passed Venus on 31 August 2025. This was its second Earth flyby. The third and last, in January 2029, will put it on its final path to reach Jupiter in 2031.

Once it's there, the plan is 35 flybys of Jupiter's three big icy moons, Ganymede, Callisto and Europa, before Juice settles into orbit around Ganymede. ESA says the Europa flybys alone have been in planning for about 10 years and won't happen until the early 2030s. All three moons are thought to hide oceans under their ice, which makes them targets in the hunt for places that could support life.

Juice is an ESA-led mission with help from NASA, JAXA and the Israel Space Agency. It's the first Large-class mission in ESA's Cosmic Vision programme.

More from Europe's planetary fleet

Juice isn't ESA's only long cruise right now. BepiColombo, its joint Mercury mission with JAXA, has just started its arrival campaign, covered in Six Months to Mercury Orbit. ESA's Earth-observation programme also launched FLEX and Sentinel-3C last month, as covered in FLEX and Sentinel-3C flew.

ESA's full flyby report is on esa.int, and the movie page with the frame-by-frame notes is here.