First Observational Evidence for Condensation of Io’s S02 Atmosphere on the Nightside
نویسندگان
چکیده
The volcanically active Jovian satellite Io has a tenuous S02 atmosphere. The color of S02 is markedly different tha]~ the color of Io as a whole in the 0.4 to 0.6 ~m region. We have exploited this fact to search Voyager 2 images for the condensation of S02 frost on its nightsicle. Measurements of the color of the dayside of Io, and the same geographical region at night. (illuminated by Jupiter’s light), indicate that the night hemisphere is significantly bluer. The most likely explanation for this difference is that S02 frost. condenses on the surface during the night, and sublimates during the clay. This is the first direct evidence for condensation of S02 frost on the nightside of Io.
منابع مشابه
The collapse of Io’s primary atmosphere in Jupiter eclipse
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