The HyperSpectral Imager for Climate Science (HySICS) is the core instrument of Absolute Refractivity and Reflectance Observatory (CLARREO) Pathfinder (CPF) mission currently scheduled to be launched International Space Station (ISS) in 2023. HySICS an Offner–Chrisp imaging spectrometer designed meet unprecedented radiometric uncertainty requirement 0.3% (k = 1) over its entire spectral range 3...