Juice Spacecraft Returns to Earth for a Gravity Boost

By Space.Fan Editorial DeskSeptember 21, 2026 at 2:00 PM UTC

The Jupiter-bound mission is swinging by our home planet to pick up speed for its long journey to the outer solar system.

Image · ESA

The Drop

The European Space Agency's Juice spacecraft is visiting Earth once again to get a major speed boost. By flying close to our , the spacecraft uses Earth's gravity to change its path and speed up without needing to burn extra fuel. This move is essential for keeping the mission on its long path to Jupiter. To make this happen, the mission team uses complex math to steer the ship. They have been making tiny adjustments to the spacecraft's path for weeks to ensure it arrives at the exact right spot. The team will be watching closely as it passes 8,640 kilometers above our world to make sure everything goes as planned. This flyby is a bit tricky because the spacecraft will pass through Earth's shadow. Without sunlight to power its solar panels, the ship must run on battery power for several hours. To keep the batteries safe, the team will turn off most of the ship's tools until it reaches the sunlight again.

Why It Matters

Traveling to the outer solar system is very difficult because of the fuel it takes to get there. If scientists tried to fly straight to Jupiter, they would need a massive rocket and tons of extra fuel just to speed up and then slow down upon arrival. Using s like Earth, the , and Venus to gain speed is a smart way to save fuel so the spacecraft has enough energy to stay around Jupiter once it arrives.

The Catch

While the mission team has carefully planned this maneuver, they must stay ready to perform emergency course corrections. There is always a small risk of navigation errors or potential contact with other satellites in orbit, which is why the team remains on high alert during the close approach.

Put That in Perspective

Launched in 2023, the Juice spacecraft is on a multi-year trip. After this visit to Earth, it will need one more flyby of our planet in 2029 before it finally reaches the giant planet Jupiter in 2031 to study its icy moons.

Source September 21, 2026

Angela Dietz

European Space Agency