In-situ chemical imager [for planetary exploration]

A variety of in-situ planetary exploration tasks such as particulate analysis or life detection require a tool with a capability for combined imaging and chemical analysis with submicron spatial resolution. In our instrument, spatially resolved chemical imaging is achieved by augmenting a fiber optic scanning probe microscope with laser induced breakdown spectroscopy. Elemental composition of surfaces can be mapped and correlated with topographical data. Experiments are conducted in ambient conditions or under vacuum with minimal sample preparation. A sharp fiber optic probe is used as a means for topographical analysis and as a delivery tool for pulsed laser radiation that vaporizes material below the probe. Optical emission from the ablation plume is analyzed with a UV/VIS spectrometer equipped with an intensified CCD detector. The ablation crater size is controlled by the amount of laser power coupled into the probe. Sampling areas with submicron dimensions are achieved by using reduced laser power.