A NASA Innovative Advanced Concepts (NIAC) initiative is studying a sensor system for probing the molecular composition of asteroids from an orbiting spacecraft. The measurement concept uses a high-power laser directed at the target; the heated spot is then viewed by a spectrometer through the plume of ejected material. To test the measurement concept in the space environment, an experiment relying on two CubeSats flying in formation is proposed. One spacecraft, the target, carries a sample material; the other is envisioned as a 6U CubeSat carrying the laser and the spectrometer along with all other subsystems necessary for formation flying. A 200 W diode laser is considered, requiring sufficient space, energy supply, and thermal control. The high-power laser cannot run continuously due to limited energy storage availability in CubeSat systems. One alternative is to optimize power usage by running successive short-duration experiments in each orbit. Energy is supplied by a battery bank, which drains during laser operation, and re-charges from a solar photovoltaic array during latent periods. A systems analysis of the energy infrastructure is presented, based on the power rate at the battery input and output throughout a simulated orbit. Solar array and battery pack configurations are simulated to optimize the experiment cycle without depleting the battery. Simulations are run in MATLAB, and results of different hardware and orbital scenarios are discussed. The 200 W laser, powered by off-the-shelf battery and solar array components, will meet all mission requirements.
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