Now the adventure in space has began for the Swedish instrument Particle Environment Package on board Juice

On July 3 the Swedish led instrument Particle Environment Package (PEP) onboard the ESA spacecraft Juice achieved a major milestone with its successful commissioning. Juice has since the launch on April 14 done a remarkable journey spanning 200 million kilometers in space.

Professor Stas Barabash at the Swedish Institute of Space Physics in Kiruna is Principal Investigator for PEP. He has several nervous weeks behind him.

Oh, it was certainly stressful. Commissioning is like releasing your child to the adult life. You prepare them for many years, thinking you have thought about everything and provided for all details but you are still nervous when they get exposed to the reality. PEP did it good. We have a mission”, says Prof. Stas Barabash.

The PEP suite includes six instruments, two of those designed and built by IRF. The instruments will explore how complex environment of Jupiter consisting of plasma and energetic particles interacts and affects the icy moons Europa, Ganymede and Callisto.

By measuring plasma and neutral gas very close to the moons surfaces, PEP will also provide critical insights in searching for moon’s subsurface oceans that may harbor life.

Five weeks of commissioning ended on July 3. Its goal is to demonstrate that the instrument is ready for operations in the harsh space environment after it was launched into space. This is a complex and important process in all scientific missions.

PEP commissioning included the first power on of the instrument computers and all the six instruments. The first phase of commissioning verified that the instruments worked as intended. It can be seen as a health check of the instrument systems and a test that it can operate and produce scientific data.

The scientific team behind PEP have checked that the basic systems work but during the journey towards the Jovian system they have to make further functional tests of the instruments’ high-voltage systems.

The travel to Jupiter will take eight years. Juice arrives to its destination in 2031. The commissioning is a milestone, the PEP story has just began”, says Stas Barabash.

More information
IRF and Juice:

Professor Stas Barabash, Swedish Institute of Space Physics in Kiruna, Principal Investigator for Particle Environment Package (PEP). , +46 980 791 22


Photo of the Particle Environment Package, PEP, (three of the six instruments NIM, JNA and JEI in the Pep suite)  – taken from the side by the onboard camera on the ESA spacecraft Juice.
Photo cred: ESA/Juice/JMC, CC BY-SA 3.0 IGO

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