Optimising Thermal Mapping Instrument Filters to Unveil Enceladus' Subsurface Secrets

Enceladus is a key target for astrobiological study, with its subsurface ocean and cryovolcanism focused at the South Pole’s ’tiger stripe’ fractures; understanding temperature variations is essential to decipher the moon’s geological activity and potential for life. Blending heritage from TechDemoSat-1, Mars Climate Sounder, and Lunar Trailblazer, the University of Oxford’s Enceladus Thermal Mapper (ETM) faces new opportunities and challenges in observing this active icy moon of Saturn. This high heritage thermal instrument will characterise Enceladus’ activity and surface properties by measuring its day, night, and polar-night temperatures, with particular focus on the tiger stripes. The winter temperatures are the most challenging, as they plunge as low as 45 K. This cold temperature regime is driving adaptations to sensor design and operations, for example requiring long exposure times and meticulous noise control.

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