Calderas And Cliffs Near Io's South Pole
Explanation:
Braving intense
radiation
belts,
the Galileo spacecraft
once again flew past the surface of Jupiter's
moon Io (sounds like
EYE-oh)
on February 22.
Combining high resolution black and white images from that
flyby with color data recorded last summer has resulted in
this dramatic view
of a region near the volcanic moon's south pole.
An active and alien landscape, the bright white areas are
likely due to sulfur dioxide frost and seem to be
concentrated near ridges and cliffs.
The three ominous black spots, each about 6-12 miles across, are
volcanic craters or
calderas covered with recent dark lava.
A sinuous channel
connects the lower left caldera with a yellowish lava flow.
Io is small, but its
continuous activity is driven by the
drastic
tides
induced by
Jupiter and the other Jovian moons.
It is estimated that the resulting
volcanism completely
resurfaces Io every million years.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.
