Interrogating the molecular composition of asteroids from a remote vantage: Progress in the laboratory

With the goal of landing crewed missions on the Moon and Mars in the next decade, mineral deposits on asteroids represent a potentially important resource for emerging space colonies. Deep-space missions can contemplate in-situ resource utilization, should suitable compounds be present. A necessary step for eventual resource exploitation is characterization of material abundances within candidate asteroids. Mineral maps could be generated by deploying CubeSat spacecraft to targeted asteroids, using Remote Laser Evaporative Molecular Absorption (R-LEMA) spectroscopy. In the R-LEMA scheme, a directed energy beam is used to probe molecular composition of a remote target. The laser-heated spot serves as a high-temperature blackbody source and ejected molecules create a plume of surface materials in front of the spot. Molecular composition is investigated by using a spectrometer to view the heated spot through the plume. Laboratory experiments allow comparison between predicted and measured profiles. Preliminary experiments described in this paper make use of solid-state samples so as to develop a library of spectra for comparison to future spectra obtained from samples in the gas phase.