Europa , potassium

Fortunately for astronomers, Europas surface has not regenerated recently. At an age of at least 10 million years, its surface can tell much about its history. NASA and others are showing interest in Europas potassium as well as the possibility that life processes should be investigated. Europa may be hiding an ocean beneath its surface. Lander missions are being considered, which would be of immense usefulness in understanding one of the most dynamic bodies of our solar system. 

Spectrally there is little to distinguish between the two opposing hypotheses, since the distortion of the water absorptions in both cases is primarily due to the highly hydrated sulfate groups with little effect from the cation involved. Indeed, there are points of agreement between the two with respect to the likelihood of sulfuric acid production in the environment and the possibility that salts may be part of the proposed radiolytic cycle. Observations of neutral atoms in the vicinity of Europa tend to favor a sodium-bearing constituent. Europa has an extended atmosphere containing both sodium and potassium (Brown, 2001 Brown and Hill, 1996). Potassium-to-sodium... 

Brown, Michael. Potassium in Europa s Atmosphere. Icarus 151 (2001) 190-195. This article discusses the research that led to a better understanding of the sodium-potassium content of Jupiter s moon Europa. 

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