July 4 (Xinhua) -- NASA's Cassini spacecraft has revealed for the first time
surface details of Saturn's moon Hyperion, including cup-like craters filled
with hydrocarbons that may indicate more widespread presence in our solar system
of basic chemicals necessary for life.
This map shows the composition of a
portion of Hyperion's surface. Blue shows the maximum exposure of frozen
water, red denotes carbon dioxide ice ("dry ice"), magenta indicates
regions of water plus carbon dioxide, yellow is a mix of carbon dioxide
and an unidentified material. (NASA Photo)
Hyperion yielded some of its secrets to the battery
of instruments aboard Cassini as the spacecraft flew close by in September 2005.
Water and carbon dioxide ices were found, as well as dark material that fits the
spectral profile of hydrocarbons.
A paper appearing in the July 5 issue of Nature
reports details of Hyperion's surface craters and composition observed during
this flyby, including keys to understanding the moon's origin and evolution over
4.5 billion years. This is the first time scientists were able to map the
surface material on Hyperion.
"Of special interest is the presence on Hyperion of
hydrocarbons -- combinations of carbon and hydrogen atoms that are found in
comets, meteorites, and the dust in our galaxy," said Dale Cruikshank, NASA's
planetary scientist, and the paper's lead author.
"These molecules, when embedded in ice and exposed to
ultraviolet light, form new molecules of biological significance. This doesn't
mean that we have found life, but it is a further indication that the basic
chemistry needed for life is widespread in the universe."
Hyperion, Saturn's eighth largest moon, has a chaotic
spin and orbits Saturn every 21 days. The July 5 issue of Nature also includes
new findings from the imaging team about Hyperion's strange, spongy-looking