PEP (Particle Environment Package) will study the interaction between space and Jupiter’s icy moons.
The instrument with its six sensors will investigate how neutral and charged particles, such as ions, electrons and atoms,
behave in the magnetosphere and the electrical fields contained in the Jupiter system.

  APL built two state-of-the-art instruments for the European Space Agency’s Jupiter Icy Moons Explorer, or JUICE, 
  mission to explore this exciting system: the Jovian Energetic Neutrals and Ions (JENI) instrument and the 
  Jovian Energetic Electrons (JoEE) instrument. JoEE is an innovative electron particle spectrometer that will 
  use 3D-printed collimators to map the processes responsible for making Jupiter the solar system’s largest particle accelerator.