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.
A phased array operates by modulating the phases of several signals, allowing electronic control over the locations that these signals interfere constructively or destructively, allowing the beam to be steered. A space-based laser phased array, called the Directed Energy System for Targeting of Asteroids and exploRation (DE-STAR) has previously been posited by our group for a number of uses, from planetary defense to relativistic propulsion of small probes. Here we propose using the same basic system topology as a receiver rather than a transmitter. All of the components in the system, excluding the laser, are bidirectional. Rather than each elements transmitting laser light, they would instead receive light, which will then be combined to create an interference pattern that can be imaged onto a focal plane. The Laser Array Space Telescope (LAST) uses most of the same components and metrology as DE-STAR and could thus be integrated into a singular system, allowing both transmit and receive modes. This paper discusses the possible applications of this system from laser communications to astrophysics.