The MAJIS/JUICE mission
MAJIS (Moons And Jupiter Imaging Spectrometer) will be an instrument on board JUICE (Jupiter Icy Moons Exploration), a science mission to explore Jupiter and three of its largest moons: Europa, Ganymede, and Calisto. After 8 years of an impressive celestial pinball voyage, Jupiter will be reached and scrutinized during 3.5 years.
- spectrally characterize the Jovian atmosphere
- determine the exospheres and global composition and surface materials of the icy moons
Two spectro-imagers for the visual and near-infrared (VIS-NIR) and infrared (IR) regions were designed by LDO (Italy) for this mission. They are located in the two measurement channels of the MAJIS instrument.
So, hot scientific topics but at cold temperature for an icy exploration! Indeed, such observations require detecting devices operating at low temperature even in the NIR band. This ‘cold heart’ of the instrument, a Teledyne detector, must be fully characterized at the laboratory, pixel by pixel, in a simulated space environment, to define its key performances before the mission.
A facility, funded by ESA (PRODEX), is being assembled in Belgium for the VIS-NIR detector (0.5 µm – 2.35 µm).
The MAJIS VIS-NIR characterization facility
BIRA-IASB (D42-D43 and Engineering department) and ROB joined efforts for this project and are in charge of the detector characterization between -153 °C and -123 °C. In 2018, they performed the detailed design of the characterization facility.
In a next step, scientists and engineers now focus on the assembly and alignment of the optics, connecting pumps, cryo-cooler and sensors, and adjusting the fine mechanics, to be in good position in 2019 to investigate the performances of the selected detectors.