Phase-angle coverage of the lunar polarimetry from the orbit using KPLO/PolCam

Onboard the Korea Pathfinder Lunar Orbiter (KPLO), a wide-angle polarimetric camera, PolCam, will investigate the lunar surface. PolCam's two identical cameras are tilted 45° from the nadir direction and look opposite sides from each other across the orbital track. This tilt angle allows us to measure the degree of linear polarization of the sunlight reflected by the lunar surface at phase-angles of up to ~140°. Since the degree of linear polarization changes with the phase-angle, it is important to perform several measurements at various phase-angles to properly estimate the polarization phase curve and derive the maximum value. In this work, we show the PolCam's phase-angle coverage as a function of selenographic longitudes of latitudinal strips from the equator up to 70°N. We also show how the high-end of the phase angle coverage is limited in case of smaller tilt angles of 25° or 0°.