AirMSPI_RADEX_Ellipsoid-projected_Georegistered_Radiance_Data is an AirMSPI ellipsoid-projected georegistered radiance product acquired during the Radar Definition Experiment (RADEX) flight campaign.AirMSPI Level 1B2 products contain radiometric and polarimetric images of clouds, aerosols, and the surface of the Earth. In particular, products contain map-projected data at 8 wavelengths: 355, 380, 445, 470, 555, 660, 865, and 935 nm. The data products include radiance, time, solar zenith, solar azimuth, view zenith, and view azimuth for all spectral bands. Wavelengths for which polarization information is available (470, 660, and 865 nm) and include the Stokes parameters Q and U, as well as degree of linear polarization (DOLP) and angle of linear polarization (AOLP). Q, U, and AOLP are reported relative to both the scattering and view meridian planes. Files are distributed in HDF-EOS-5 format.This release of AirMSPI data contains all targets acquired during the Radar Definition Experiment (RADEX) flight campaign, which was based out of Joint Base Lewis-McChord, Washington. The campaign focused on characterizing new radar instruments being tested for future NASA satellite missions with AirMSPI providing additional cloud characterization. AirMSPI data were acquired from November 10 through December 13, 2015.