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Aug 4, 2013
Io's Surface: Under Construction
Image Credit & Copyright: Astronomy Picture of the Day -- http://apod.nasa.gov/apod/astropix.html
Courtesy of http://apod.nasa.gov/apod/astropix.html
Io's Surface: Under Construction
Image Credit & Copyright: Astronomy Picture of the Day -- http://apod.nasa.gov/apod/astropix.html
Courtesy of http://apod.nasa.gov/apod/astropix.html
Like the downtown area of your favorite city
and any self-respecting
web site ...
Io's surface is constantly under construction.
This
moon of Jupiter holds the
distinction of being
the Solar System's most volcanically active body --
its bizarre looking surface continuously
formed and reformed by lava flows.
Generated using 1996 data from NASA's Galileo spacecraft,
this
high resolution composite image
is centered on the side of Io that always faces away from Jupiter.
It has been enhanced to emphasize Io's surface brightness
and color variations, revealing features as small as 1.5 miles across.
The notable absence of
impact craters
suggests that the entire
surface is covered with new volcanic deposits much more rapidly
than craters are created.
What drives this volcanic powerhouse?
A likely energy source is the changing gravitational
tides caused by Jupiter and the other
Galilean moons as Io orbits the massive gas giant planet.
Heating Io's interior, the pumping tides would generate
the sulfurous volcanic activity.
