Investigating Europa’s Ice Shell and Ocean

Uniquely designed to measure characteristics of the charged gases around Europa while resisting the fierce radiation around Jupiter, the Plasma Instrument for Magnetic Sounding (PIMS) will provide details to better understand the water ocean beneath the moon's surface.

About the Instrument

Instrument Type

The APL-built Plasma Instrument for Magnetic Sounding (PIMS) is part of NASA’s Europa Clipper mission, which targets Jupiter’s icy moon, Europa. An ocean world, Europa is a moon with a liquid water ocean sloshing beneath its surface, making it one of the prime destinations to search for life beyond Earth.

PIMS Instrument
A detailed, 3D rendering of the Europa Clipper PIMS instrument, showing two of its specially designed Faraday cups to measure plasma around Jupiter's moon Europa.

PIMS will measure the plasma — a soup of electrically charged gas — that fills Jupiter’s magnetosphere and makes up the charged part of Europa’s atmosphere, called the ionosphere. As Jupiter’s magnetic field washes over Europa, it induces a magnetic field within the subsurface ocean. That induced field can reveal details about the thickness of the moon’s ice shell, the depth of its subsurface ocean and the ocean’s salinity. Plasma in Jupiter’s magnetosphere, however, can skew observations of this induced magnetic field and muddy our interpretations of it. Using four specially designed sensors called Faraday cups, PIMS will provide clarity by measuring characteristics of the low-energy plasma at and around Europa — including the plasma density, temperature and velocity — to help uncover what Europa’s induced magnetic field is telling us about the ocean beneath.