Low-energy laser induced breakdown spectroscopy for in-situ space missions to solar system bodies without atmospheres

Several space missions to bodies in the solar system consider landers or rovers, which are equipped with laser-induced breakdown spectroscopy (LIBS) instruments as part of the scientific payload. LIBS is capable of providing in-situ quantitative elemental analyses of all major and many minor and trace elements of the planetary surface material. Here we focus on the investigation of a particular LIBS application scenario, namely a miniaturized LIBS instrument with a low-energy laser operating in ultra-high vacuum (below 1 mPa). Such a scenario is relevant for exploration of asteroids, our Moon or Jupiterʹs moon Europa. We demonstrate that an excitation energy of only ∼1 mJ from an infrared laser is sufficient for the formation of a plasma. Elements more abundant than 0.1 wt% in a sample can be detected with sufficient signal-to-noise ratios within about 100 s acquisition time and for a laser irradiance below 50 MW/mm2.