JANUS Camera on the JUICE Mission

jupiter
juice
instrumentation
python
Author

Michael Aye

Published

March 4, 2026

JANUS (Jovis, Amorum ac Natorum Undique Scrutator) is the optical camera system on ESA’s JUICE mission to the Jupiter system. It will image Jupiter’s atmosphere, the Galilean moons — particularly Ganymede, Europa, and Callisto — and the broader Jovian environment at visible and near-infrared wavelengths.

My work on JANUS focuses on radiometric calibration, exposure time calculation, and signal-to-noise analysis. I developed the janus-nbexposure Python package for computing expected signal levels and optimal exposure times across JANUS observing scenarios, accounting for detector characteristics, optical throughput, and target radiance — including reflected Jupiter-shine on the icy moons.

This work supports observation planning and helps ensure that JANUS achieves its science objectives within the instrument’s operational constraints. Funded by the German Federal Ministry of Education and Research (BMBF) through DLR (grant 50QJ2404).