In the future, small portable or handheld XRF instruments could prove extremely useful for missions of scientific exploration in the inner Solar System. Such instruments on missions that employ rovers could transmit geochemical data back to Earth for adaptive traverse planning, and could inform sample collection and archiving for future return to Earth. Rapid contact analysis by hXRF may be especially desirable for use by astronaut geologists given the tight time constraints of extravehicular activity (Hodges and Schmitt, 2011).