Ion‐Selective Electrode Robustness to Environmental Conditions Relevant to Spaceflight Missions to the Outer Solar System

The utility of ion‐selective electrodes (ISEs) for solar system exploration was proven during the NASA Mars Phoenix Lander mission, where they were used to assess environmental habitability by quantifying soluble ions in surface regolith and ice. Future in situ missions to ocean worlds of the outer Solar System would benefit from the aqueous chemical measurements provided by ISEs. Here, we verify the performance of ISEs after exposure to specific environmental stressors that can be encountered during outer Solar System missions, specifically near‐decade scale transit times, anhydrous conditions, low‐temperature extremes (−20° and −80°C), and high radiation doses (300 krad). ISE performance was verified using a combination of calibration and selectivity testing, and under all conditions, tested ISE performance was unaffected by the environmental stressors applied.