Night-time remote sensing: understanding the science and measurement challenges

Future space missions of Earth Observation propose to use night-time remote sensing to target new observables that represent a long-standing observational gap or address urgent scientific and societal research questions. The key challenges to enable such missions are related to the capability of the payload to measure very low radiances and with an extremely large dynamic range, ranging from night-time radiances to day-time radiances. In this paper, we derive the flow-down for such missions: from the scientific objectives, we derive the measurement requirements, on which we perform trade-offs based on mission analysis and radiometric budget. Subsequently, we identify potential detectors for these missions, and we identify the gaps in current state-of-the-art technology.