PolSIR 1, 2

PolSIR [NASA/JPL]

PolSIR (Polarized Submillimeter Ice-Cloud Radiometer) is a pair of small CubeSat satellites with the goal is to understand the influence of ice clouds on the climate. Ice clouds have been identified by the Intergovernmental Panel on Climate Change (IPCC) as one of the biggest unknowns in the understanding of the climate system and how it changes.

The PolSIR mission consists of two 12U CubeSats, each equipped with a six channel, cross-track scanning polarized submillimeter radiometer in the spectral range of 325–680 GHz.

The two PolSIR satellites fly in separate, 51° inclination, non-sun-synchronous orbits, taking science measurements between ±35° latitude enabling monthly sampling of the diurnal cycle of ice clouds and their microphysical properties in the tropics and sub-tropics. PolSIR’s observation concept provides significant benefits over the Program of Record (PoR) as well as synergies with future missions which will either be in sun-synchronous orbits, thus not sampling the diurnal cycle, or lack the observation frequencies needed to fully observe ice water path (IWP).