New Home for the Flight Spare Unit of PEP-JEI

The particle spectrometer PEP-JEI for the Jupiter mission JUICE has arrived safely in Kiruna (Sweden).

The flight spare unit of the Jovian Electron and Ion Sensor (JEI) has left the Max Planck Institute for Solar System Research (MPS) in Göttingen (Germany) and has now taken up residence at the Swedish Institute of Space Physics (IRF) in Kiruna (Sweden). JEI is part of the PEP (Particle Environment Package) instrument package that will travel to the Jovian system next year aboard ESA's JUICE (Jupiter Icy Moon Explorer) spacecraft to measure the distribution of electrons and ions in the gas giant's environment.

JEI is one of the contributions of the Max Planck Institute for Solar System Research (MPS) to the JUICE mission. The sensor's flight unit, which was developed and built at the MPS, was integrated into the spacecraft more than a year ago and is currently undergoing final preparations in the clean rooms of Airbus Defense and Space in Toulouse (France), and later at ESA in Noordwijk (Netherlands). In early 2023, the spacecraft will be transported to the launch site in Kourou (French Guiana) and is scheduled to launch into space in April 2023.

In the meantime, the scientific and technical teams at MPS have completed JEI’s flight spare unit. The identical twin can be swapped with the flight unit if difficulties arise, or it can remain on the ground throughout the mission and help interpret the flight unit's measurement data from the Jovian system or simulate command sequences. At the IRF in Sweden, which leads the PEP team, all flight spare units of PEP’s six sensors will now find a new home – possibly until the mission ends in the 2030s.

JEI's flight spare unit has arrived safely and has already been commissioned on s