Colloquium: Dr. Erica Venkatesulu | Montana State University
In-Person PHYS 401
Location
Physics : 401
Date & Time
October 22, 2025, 11:00 am – 12:00 pm
Description
TITLE: "Measurements and model of disk-averaged Moon polarization”
ABSTRACT: The Moon can be used as a stable calibration target for on-orbit satellite instruments without the need for solar diffusers or atmospheric correction. Lunar radiance models have enabled radiometric characterization of many on-orbit instruments. However, the Moon has a polarization state that varies with lunar phase angle and wavelength, so accounting for lunar polarization is critical for accurate calibration of polarization-sensitive satellite instruments. In this work, we recorded measurements of the polarization state of moonlight in five visible and near infrared spectral channels (centered at 450 nm, 520 nm, 650 nm, 800 nm, and 900 nm) as well as a broadband channel. We used those measurements combined with previously published measurements to develop a model of the disk-averaged polarization of the Moon in bands ranging from 336 nm to 900 nm. This talk describes the polarization imager we used and its calibration, the measurements of Moon polarization, and the resulting model.
ABSTRACT: The Moon can be used as a stable calibration target for on-orbit satellite instruments without the need for solar diffusers or atmospheric correction. Lunar radiance models have enabled radiometric characterization of many on-orbit instruments. However, the Moon has a polarization state that varies with lunar phase angle and wavelength, so accounting for lunar polarization is critical for accurate calibration of polarization-sensitive satellite instruments. In this work, we recorded measurements of the polarization state of moonlight in five visible and near infrared spectral channels (centered at 450 nm, 520 nm, 650 nm, 800 nm, and 900 nm) as well as a broadband channel. We used those measurements combined with previously published measurements to develop a model of the disk-averaged polarization of the Moon in bands ranging from 336 nm to 900 nm. This talk describes the polarization imager we used and its calibration, the measurements of Moon polarization, and the resulting model.
