Raman/CHAMP Instrument for Lunar In-situ Resource Prospecting I - Imager Design

Abstract

Lunar ISRU precursor prospecting missions are being considered in order to characterize the lunar surface environment and to determine volatile and mineral content as well as mechanical and thermal properties of the lunar regolith for purposes of designing future excavation and In-Situ Resource Utilization (ISRU) processing equipment. The Raman/CHAMP instrument (RCI) is being developed as part of an instrument/experiment suite development project known as Regolith and Environment Science and Oxygen and Lunar Volatile Extraction (RESOLVE) being developed and sponsored under the NASA ISRU Project. The RCI supports the lunar surface characterization measurements by providing crucial field macroscopic and microscopic images coupled with Raman spectroscopy. The RCI provides the ability to collect high resolution, hand lens to field microscopy images and spectroscopic measurements from a robotic arm with the ability to resolve, characterize, and chemically differentiate >90% of lunar Apollo fines. The entire measurement process is highly adaptive and does not necessarily require any type of active sampling. In this paper we provide an overview of the RCI. We discuss the optical design optimization and analysis process for this particular type of instrument. We discuss recent results of integration tests of the Mars Microbeam Raman Spectrometer (MMRS) with the MIDP CHAMP instrument, fluorescence analysis, and individual glass fluorescence tests. Finally, we conclude with a summary of anticipated instrument measurement performance based on Zemax optical modeling of an RCI engineering model that is currently in development.