The Hyper-Angular Rainbow Polarimeter (HARP) is a wide field-of-view imaging polarimeter instrument designed for accurate and comprehensive measurements of aerosol and cloud properties from space. The HARP instrument fits in a 1.5U volume, with microelectronics and telemetry optimized for a 3U CubeSat spacecraft. The HARP CubeSat mission is a NASA ESTO InVest project, with joint collaboration between the Earth and Space Institute at UMBC and the Space Dynamics Laboratory (SDL) at Utah State University.
The HARP CubeSat simultaneously samples at 120 unique viewing angles, 4 visible wavelengths, and 3 unique polarization states. Using a combination of polarized information from three co-aligned CCD detectors, the HARP CubeSat produces geolocated, georegistered, gridded, and calibrated Stokes parameters I, Q, and U at narrow spatial resolutions. The polarization separation is done with a modified Phillips prism and wavelength selection via stripe-filter detectors: both advancements in tandem are the key to high polarization accuracy with no moving parts and miniaturization into a CubeSat payload. The HARP CubeSat is scheduled to launch from the orbit of the International Space Station (ISS, 400km) no earlier than November 17th, 2018, for a mission lifetime of one year. The HARP CubeSat science mission will be carried out by the UMBC Department of Physics and the mission operations by SDL.
The HARP CubeSat was replicated into AirHARP, an airborne demonstration of HARP technology, for use on NASA aircraft campaigns. AirHARP participated in the Lake Michigan Ozone Study (LMOS) and the Aerosol Characterization from Polarimeter and LiDAR campaigns in 2017 to demonstrate HARP technology and provide practice datasets for the upcoming HARP CubeSat deployment.