Ancillary Information for the prime products

Abstract

This document describes the Ancillary Information for the prime products. The Jovian Infrared Auroral Mapper (JIRAM, Adriani et al., 2017) is an imaging spectrometer on board the Juno spacecraft, which started observing Jupiter on August 2016 (Bolton et al., 2017). The JIRAM scientific goals are to explore the Jovian aurorae and the planet’s atmospheric structure, dynamics and composition. The main auroral oval emission has been investigated by JIRAM since orbit insertion (2016), as well as the thermal emission from the atmosphere. All technical information on JIRAM instrument can be found in Adriani et al., (2017). In summaty JIRAM has two imaging channel (L-band and M-band) and one spectrometer channel. Both JIRAM L-band and M-band imaging channels acquire images (128 x 432 pixels each), with a pixel angular resolution is 0.01°. The FoV of both bands is 5.87° by 1.74 ° degrees; the spatial resolution, at the surface, varies along the spacecraft distance and it is of the order of 100 km. The integration time for L-band (auroral images) is always 1 s, while for the M-band (atmosphere) it is of the order of 10 ms, The spectrometer acquires 256 spectra, from 2 to 5 μm with 9nm spectral sampling, arranged along a 1D slit (the spectrometer data is not used in this dataset)Because Juno is a spinning spacecraft, there is a dedicated de-spinning mirror that compensates for the spacecraft rotation. For this reason, the instrument can perform only one acquisition for each spacecraft turn (that is, every 30 s), made both 2 images (2 filters) and one slit of spectra. By setting the time of the observation, and taking advantage of the rotation of Juno, JIRAM can tilt its field of view (FoV) above or below the sub-spacecraft point, along the plane perpendicular to Juno spin axis. JIRAM cannot articulate its FoV in any other direction without turning the spacecraft.