Sunlight can be reflected into permanently shadowed regions (PSRs) using S/C solar sails in order to detect and confirm the presence and distribution of water ice cold-trapped in PSRs in lunar polar craters. This reflected light is then viewed with an optical spectrometer.
HEOMD AES (Human Exploration and Operations Mission Directorate Advanced Exploration Systems) has identified a strategic knowledge gap — the presence, quantity, and distribution of water ice cold-trapped in lunar PSRs. Existing or prior assets have provided ambiguous evidence for the presence of water in PSRs, and there is a desire to investigate using the water-absorption features at 1 to 3 μm using a CubeSat, but there is a lack of a viable illumination source. Reflecting sunlight from the CubeSat’s solar sail can provide the required illumination.