Unique Heliospheric Measurement Opportunities with the ESA JUICE mission: Science Case for Particle Environment Package (PEP)

The Jupiter bound JUICE mission (JUpiter ICy moons Explorer) was successfully launched on April 14, 2023 and is currently executing its 8-year interplanetary cruise phase. JUICE carries three comprehensive instrument suites to fully characterize particles, fields, and waves. The JUICE space plasma instrumentation constitutes the most comprehensive and capable heliophysics payload ever flown, or planned, in the important but not-well explored the solar system region between 1 and 5 au.

Science objectives that can be addressed by the JUICE payload include solar wind evolution, collisionless shock interactions and propagation, and particle acceleration, solar energetic particles, pick-up ion (PUI) origin and evolution, turbulent interactions, energetic neutral atom (ENA) imaging, and interplanetary hydrogen observations.

JUICE enables an expansion of inner heliospheric science, connecting to observations in the outer heliosphere and Very Local Interstellar Medium (VLISM) by NASA’s New Horizons, Voyager, and Interstellar Mapping and Acceleration Probe (IMAP) (to launch Feb 2025). New science opportunities are also enabled by the simultaneous observations from Europa Clipper in the same region. JUICE will spend the next six years between 0.7 au and 2.5 au, and in 2029-2031 it will explore the region out to Jupiter. JUICE has no thermal constraints past 1.34 au and the data volume from relevant sensors live well within the available data downlink through its weekly passes using the European Space Tracking (ESTRACK).

In this presentation, we discuss the unique heliophysics observations the six-sensor suite Particle Environment Package (PEP) on board can do in conjunction with other space physics measurements on board JUICE and Europa Clipper. The PEP-suite measures species-resolved energy and angular distributions of electrons (~ 1 eV to ~1.5 MeV), ions (~1 eV to > 10 MeV; energy rage is species dependent); and ENA (~ 5eV to 300 keV). In addition to the PEP instrument suite, JUICE also carries a radiation monitor (RADEM) that can provide complimentary energy and species resolved measurements of very energetic electrons and ions in the solar wind.