Saturn's moon Titan continued to surprise scientists during a
flyby that took Cassini into regions previously unexplored by
radar. Two very noticeable circular features, possible impact
craters or calderas, appear in the latest radar images taken
during the flyby on April 30, 2006. |This circular feature might
be an impact crater or a cryovolcanic caldera. Image credit:
NASA/JPL The flyby targeted Xanadu, one of the most prominent
features on Titan, visible even from telescopes on Earth. The
origin of Xanadu is still unknown, but the radar images reveal
details previously unseen, such as numerous curvy features that
may indicate fluid flows. Scientists speculate that two
prominent circular features are probably impact craters but they
don't rule out the possibility that they might be calderas or
volcanoes. Sand dunes, discovered in previous flybys, continue
to crisscross Titan's surface. Communication from the spacecraft
was temporarily interrupted for nearly five hours during the
data playback following the