Explanation:
Although its colors may be subtle, Saturn's moon Helene is an enigma in any light.
The moon was imaged in
unprecedented detail last June as the
robotic
Cassini spacecraft orbiting Saturn
swooped
to within a single Earth diameter of the
diminutive moon.
Although conventional craters and hills
appear, the
aboveimage also
shows terrain that appears unusually smooth and streaked.
Planetary astronomers are inspecting these detailed images of
Helene to glean
clues
about the origin and evolution of the 30-km across floating iceberg.
Helene is also unusual because it circles
Saturn just ahead of the large moon
Dione, making it one of only
four known Saturnian moons to occupy a gravitational well known as a stable
Lagrange point.
Dark Mysteries:
Astronomy Seminar of the Week
