Europa Clipper: What NASA Hopes to Find Beneath the Ice
Europa is an icy moon that circles the planet Jupiter. Beneath its ice may lie an ocean with more than twice as much water as all of Earth's oceans. NASA's robotic spacecraft Europa Clipper is on its way to find out whether that hidden world has the conditions life needs.
Life on Earth needs water, certain chemicals and a source of energy. Clipper will look for those conditions on Europa, but it isn't designed to detect living things.
Why Scientists Think There's an Ocean
Europa's surface gave the first hints that something was happening below. Earlier spacecraft photographed cracks and ridges across the ice, along with relatively few large craters. The surface looked as if it had been reshaped over time.
Then Galileo, a NASA spacecraft that explored Jupiter, picked up changes in the magnetic forces around the moon. A salty ocean below the ice could explain those readings, as NASA's account of the ocean evidence describes. No camera had seen the water itself.
But how could water stay liquid so far from the Sun?
Jupiter supplies part of the answer. As Europa travels around the planet, Jupiter's changing pull stretches and squeezes the moon. That repeated movement creates heat inside, which may help keep the ocean from freezing.
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What Clipper Can Learn From Above
Clipper will study Europa while flying past it. It won't land or drill through the ice, so its team must work out what's below from clues gathered above.
Its cameras will map cracks and ridges in detail. A heat camera will look for warmer patches that might point to recent activity, giving scientists a reason to examine a particular spot more closely.
To look beneath the surface, radar will send radio waves into the ice and measure the echoes that bounce back. Those echoes could reveal buried layers or pockets of water. How far the signals reach depends on the ice, so a view all the way down to the ocean isn't guaranteed.
Other equipment will study chemicals in material on the surface and drifting above it. Measurements of magnetic forces will help estimate how deep and salty the ocean is. NASA's science plan brings these clues together to build a picture of the hidden ocean.
Inside Europa Clipper’s Scientific Instrument Suite
How It Will Survive the Visits
Collecting those clues comes with a problem. Europa sits in a region of intense radiation, where fast-moving particles can damage a spacecraft's electronics.
So NASA's flight plan sends Clipper around Jupiter, with nearly 50 close passes of Europa along the way. Each pass, called a flyby, gives it a chance to study the moon. Then it will move farther away, limiting the time it spends in the harshest radiation. Repeated visits will let the team examine different regions.
A protective box inside the spacecraft will shield sensitive electronics from radiation. Huge solar panels will collect sunlight for power this far from the Sun. With its panels open, the spacecraft spans more than 100 feet.
Meet the Spacecraft Bound for Europa’s Hidden Ocean
The Long Way to Jupiter
Clipper launched on October 14, 2024, but it still has years of travel ahead. The route includes swings past other planets, using their gravity to change the spacecraft's path and speed. These moves are called gravity assists.
The spacecraft passed Mars on March 1, 2025. Scientists also used the visit to check its heat camera against known temperatures on Mars, helping them judge how accurately it worked.
As of November 11, 2026, an Earth pass is planned for December 2026. NASA's current timeline puts arrival at Jupiter in April 2030.
The close study of Europa begins later. The team must first guide Clipper into a path that sets up its repeated visits. The first close pass of Europa is planned for spring 2031, with the first round of detailed observations beginning that May.
New Clues, and a Catch
Even while Clipper travels, old observations are giving its team places to investigate. In January 2026, NASA reported possible signs of chemicals containing ammonia in Galileo's 1997 data. Those signs appeared near cracks in Europa's surface.
Ammonia contains nitrogen, an ingredient life uses, and can help water remain liquid at lower temperatures. The clues give Clipper's team places to check, but they don't reveal whether the material came from the deep ocean or somewhere closer to the surface.
A separate study reported by Rutgers University in July 2026 shows why that distinction matters. Researchers used computer models to test whether ocean water could rise through cracks in the ice. In their simulations, water cooled quickly against the cold walls. Freezing could then block its way upward.
Their work suggests a pocket of water near the surface might form from ice melting nearby, without being fed by the ocean. Finding one wouldn't automatically reveal what the deep ocean is like. The model tested one possible route, so other ways for water to move through the ice remain open questions.
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That's the challenge waiting for Clipper. An interesting chemical or a warm patch needs context. Comparing the chemicals, buried layers and heat at the same locations could show scientists where to focus a closer search for life.
