PERISCOPE: PERIapsis Subsurface Cave OPtical Explorer (PERISCOPE)

In this NIAC report we present a new technique enabling a practical option for mapping these structures at a relatively low cost: Photon Time-of-Flight (PTOF) imaging. Human beings will eventually have a continuous or permanent presence on the moon. Caves provide multiple benefits for future crewed missions: protection from the extreme temperature swings on the surface, the possibility of resources, and simplified local habitat construction using ready-made structure. PERISCOPE offers HEOMD a way to investigate both questions with one low-cost mission. Photon time of flight imaging can map the interior structures of lunar skylights and potentially characterize elemental distribution within the caves. Knowledge of ice distribution in various caves would be valuable for future crewed visits as both a possible source of consumables as well as fuel. The PERISCOPE concept can contribute significantly to the NASA SMD long-term goals of understanding our solar system and the bodies within it. The Earth's Moon is a particularly valuable target, because it preserves a record of exogenic processes in the Earth-Moon system, and thus the history of impacts (which wreaked havoc on early Earth.) Volatile deposition and space weather on the Moon has direct relevance to that on Earth. Due to its proximity, it is also a cost-effective target, and a likely staging post for human exploration of the Solar System.