Snow and Water Imaging Spectrometer (SWIS): optomechanical and system design for a CubeSat-compatible instrument

The Snow and Water Imaging Spectrometer (SWIS) is a fast, high-uniformity, low-polarization sensitivity imaging spectrometer and telescope system designed for integration on a 6U CubeSat platform. Operating in the 350-1700 nm spectral region with 5.7 nm sampling, SWIS is capable of simultaneously addressing the demanding needs of coastal ocean science and snow/ice monitoring. We discuss progress in the SWIS optomechanical design, thermal analysis, and mission plan. We also describe an innovative single drive on-board calibration system capable of addressing the stringent radiometric stability and knowledge these missions require. The spectrometer features a new Teledyne CHROMA array, optimized for high temperature operation, with a linear variable anti-reflection coating to enhance quantum efficiency and minimize backscatter.