Mass Spectrometer Experiment for a Uranus Probe

Abstract Uranus distinguishes itself from other planets in the Solar System with a range of remarkable attributes, including a magnetosphere with a unique configuration, its quiescent atmosphere, its heating imbalance, its dense and narrow rings, and its unusually dark and tectonically processed icy satellites. Yet no mission to date has investigated either this ice giant or Neptune from up close. A Uranus Orbiter and Probe has thus been identified as the highest-priority new NASA Flagship mission for initiation in the decade 2023–2032. One invaluable instrument on a Uranus probe is a mass spectrometer experiment that analyzes the planet’s chemical composition in situ in real-time during the probe’s descent through the atmosphere. The selection of a mass spectrometer experiment is profoundly driven by the scientific questions the mission seeks to address and necessitates the accurate measurements of crucial elements including their isotope ratios. In addition to fulfilling the posed science requirements, the chosen experiment must adhere to stringent constraints such as mass, power, and size limitations while also prioritizing speed, simplicity of operation, a high level of reliability, and a completely autonomous operation. Here, we offer a succinct overview of the scientific rationale driving the Uranus probe mission, exploring various potential configurations for the mass spectrometer experiment, detailing instruments that complement a mass spectrometer, and discussing key factors that influence the mission’s profile. We also address the possibility of a collaborative effort between NASA and ESA, which could play a pivotal role in ensuring the successful development of this groundbreaking mission.