The Mapping Imaging Spectrometer for Europa (MISE): Science and Instrument Critical Design.

The Mapping Imaging Spectrometer for Europa (MISE) on the Europa Clipper Mission is being designed as a high-optical-throughput pushbroom imaging spectrometer capable of collecting spectra from within Europa's challenging radiation environment. The design uses a f/1.4 Dyson spectrometer with a CaF₂dispersive element and a 3-mirror, off-axis telescope that views through an articulated flat mirror with ± 30° of motion. The focal plane assembly is a mechanically cooled HgCdTe 320×480-pixel CHROMA device that operates at 85K. MISE is controlled by a Data Processing Unit (DPU), which includes the spacecraft communication interface, power supply, scanner electronics, on-board memory, and instrument processing. Planned on-board processing includes identifying and discarding radiation noise and aggregating the cleaned spatially oversampled data into final high-SNR image cubes.

The main science objective of MISE is to investigate the habitability of Europa by mapping the distribution of key compounds at geologically relevant spatial scales. There are two goals: 1) Assess the habitability of Europa's ocean by understanding the inventory and distribution of surface compounds and 2) Investigate the geologic history of Europa's surface and search for areas that are currently active. MISE is being designed to cover a spectral range of 800-5000 nm with 10-nm spectral sampling, enabling the identification of organics, salts, acid hydrates, water ice phases, altered silicates, radiolytic compounds and warm thermal anomalies. Operation plans are being developed that could enable the mapping of these materials across the surface of Europa to produces data sets at local (<25 m/pixel), regional (<500 m/pixel), and global (<10 km/pixel) scales.

The MISE development is a collaboration between NASA's Jet Propulsion Laboratory (California Institute of Technology) and the Applied Physics Laboratory (John Hopkins University). MISE successfully completed its Preliminary Design Review (PDR) in July 2018 and is proceeding to its Critical Design Review (CDR).