Explanation:
What processes formed the unusual surface of Saturn's moon Tethys?
To help find out,
NASA
sent the
robotic Cassini spacecraft right past the enigmatic ice moon in 2005.
Pictured above is one of the highest resolution images of an entire face of Tethys yet created.
The pervasive white color of
Tethys is thought to be created by
fresh ice particles continually falling onto the moon from Saturn's diffuse
E-ring -- particles expelled by Saturn's moon
Enceladus.
Some of the unusual cratering patterns on
Tethys
remain less well understood, however.
Close inspection of the
above image
of Tethys' south pole will reveal a
great rift running diagonally down from the middle:
Ithaca Chasma.
A leading theory for the creation of this
great canyon is anchored in the tremendous moon-wide surface cracking that
likely occurred when
Tethys' internal oceans froze.
If so, Tethys may once have
harbored
internal oceans, possibly similar to the underground oceans some hypothesize to exist under the
surface of Enceladus today.
Might ancient life be frozen down there?
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