Europa Clipper launch
On 14 October 2024 Europa Clipper, the largest planetary spacecraft NASA has built, set off to study the ocean beneath the ice of Jupiter's moon Europa. After gaining speed from flybys of Mars and Earth, it is due to reach Jupiter in April 2030.
Available views: Orbit ✓ · Sky — (not visible in the sky)
The story
On 14 October 2024 Europa Clipper left Kennedy Space Center in the United States on a Falcon Heavy rocket, bound for Jupiter. It is the largest spacecraft NASA has built for exploring planets. With its solar panels unfolded it measures 30.5 m from tip to tip, longer than a basketball court. Near Jupiter sunlight is only about one twenty-fifth as strong as at Earth, so panels this large are needed to make electricity.
Its target is Europa, one of Jupiter's moons. Europa is covered by a thick shell of ice, and scientists think a salty ocean lies beneath it. That ocean may hold more water than all of Earth's oceans put together. While circling Jupiter, Clipper is planned to pass close to Europa 49 times, studying things like the thickness of the ice and what the surface is made of.
Clipper does not fly straight to Jupiter. On 1 March 2025 it passed 884 km above the surface of Mars to change its speed. On 3 December 2026 it is due to swing past Earth for another boost, and it will reach Jupiter in April 2030. Borrowing a planet's gravity to gain speed in this way is called a gravity assist.
A few months before launch, engineers found a problem: some parts of the spacecraft might not stand up to Jupiter's strong radiation as well as expected. After months of retesting, they decided the mission could still be carried out, and the launch was then delayed from 10 to 14 October by Hurricane Milton. The orbit view reproduces Clipper's route past Mars and Earth on its way to Jupiter.
Mission goals
Europa is one of the strongest candidates in the solar system for a place where life might be able to exist today. Life is thought to need liquid water, a source of energy and the right chemical ingredients. Observations by the Galileo spacecraft and the Hubble Space Telescope gave clues that these conditions might exist beneath Europa's ice. Clipper will look directly at whether they are really there.
Instead of circling Europa, Clipper will travel on wide loops around Jupiter and swing past Europa again and again. Jupiter's radiation near Europa is so intense that a spacecraft staying there would soon be damaged. The route is designed so that each pass crosses a different part of Europa, allowing nearly the whole surface to be studied over the 49 flybys.
The mission will also act as a map for a future spacecraft that might land on Europa. Finding places where the ice is thin, or where water may spray out through cracks, would help decide where a lander should touch down. Together with ESA's JUICE, which reaches Jupiter at around the same time, it will add to our understanding of Jupiter's moons.
Mission chronology and background
Plans to explore Europa changed several times over more than twenty years. In the 2000s there was a plan for a nuclear-powered spacecraft called the Jupiter Icy Moons Orbiter, but it was cancelled. Later, to save money, the present approach was chosen: flying past Europa many times instead of circling it. The name Clipper comes from the fast sailing ships that crossed the oceans in the nineteenth century.
Which rocket to use was also debated. The original plan was NASA's large SLS rocket, but there were worries that vibrations during launch could strain the spacecraft, as well as concerns about cost. In 2021 the choice switched to Falcon Heavy, with a launch cost of about 178 million US dollars. In return, the spacecraft takes a longer route using the gravity of Mars and Earth, so the trip to Jupiter takes about five and a half years.
The spacecraft carries a metal plate engraved with a poem written for Europa by US poet laureate Ada Limón. It also carries the names of about 2.62 million people from around the world who sent them in. ESA's JUICE, launched earlier in April 2023, is due to reach Jupiter in July 2031, so Clipper will arrive first despite leaving later.
Other milestones of this mission
- Europa Clipper Earth flyby(planned)
- Europa Clipper reaches Jupiter(planned)
Where to see it — sky and simulator
Europa Clipper was launched at 12:06 p.m. US Eastern time on 14 October 2024 from Launch Complex 39A at Kennedy Space Center. Once away from Earth the spacecraft cannot be seen with the eye. The next major milestones are an Earth flyby on 3 December 2026 and arrival at Jupiter in April 2030. The Mars flyby was completed on 1 March 2025.
The orbit view reproduces the route in time order: starting from Earth at launch, passing Mars and then Earth, and curving out toward Jupiter's orbit. Following the spacecraft at high speed shows Earth and Mars sliding past as Clipper makes a loop near the Sun. If the replay continues, the spacecraft can be seen passing Earth again and then stretching far out toward Jupiter.
Jupiter shines brightly in the night sky, so it is easy to find with bare eyes. Through binoculars, four tiny dots appear beside it; these are the Galilean moons, including Europa. Selecting Jupiter in the sky view shows which side of the planet Europa is on right now. Europa goes around Jupiter about every 3.5 days, so its position changes noticeably within a few days.
See this for yourself — replay the moment in the orbit view
FAQ
When does Europa Clipper reach Jupiter?
It is due to arrive in April 2030. It passed Mars in March 2025 and is due to swing past Earth on 3 December 2026.
Why does it not orbit Europa itself?
Jupiter's radiation near Europa is so strong that a spacecraft staying there would soon break down. Circling Jupiter on wide loops and passing Europa 49 times lets it survive much longer.
How big is the spacecraft?
It is 30.5 m across with its solar panels unfolded, and it weighed about 6,065 kg at launch, of which about 2,750 kg was propellant.
Does it search for life directly?
No. It studies the ice thickness, the ocean and the surface makeup to judge whether the environment could support life. Searching for life itself is a task for future missions.
Related
Times and figures are approximate — verify with official sources when planning travel. Simulation uses J2000 mean elements.