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Unformatted text preview: ball shape is not constant but waxes and wanes (flexes) as the gravity differential changes
along Io’s orbit. This flexing heats Io’s interior by shear friction. The situation is prevented from
damping out (Io’s orbital eccentricity is maintained) by resonances with Europa and Ganymede. Io: Volcanic Activity
Plumes such as the one below
imaged along the limb of Io
provide clear evidence that
Io is volcanically active. Io: Volcanic Activity
Io’s surface is devoid of impact
craters and must therefore be
very young. Resurfacing (renewal
of the surface) is very active on Io.
The multicolored deposits on Io are
due to various sulfurrich compounds
emplaced by Io’s volcanic activity.
Bright white deposits are due to SO2
(sulfur dioxide) frost.
There is no evidence for H2O on Io. Io’s initial endowment in H2O must now
be gone. The H escaped and the O recombined with sulfur S to form SO 2. Io: Volcanic Activity
Io: Volcanic Activity Between 1979 and 1981: patterns of volcanic deposits clearly changed as well. Io:
As a result of
on a global sca...
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- Spring '11