There are
hundreds of millions of miles of the void of space between climate scientists
and Saturn's frigid moon Titan. But in spite of the distance, the scientists
nearly got it right when they made a model of the moon's climate. The only
thing off was the timing.
Scientists
found that the way clouds
are distributed around Titan mostly matches their models. Contrary to
predictions, however, clouds still have not dissipated from the southern
hemisphere as the moon's fall season approaches.
"Titan's
clouds don't move with the seasons exactly as we expected," Sebastien Rodriguez
of the University of Paris Diderot, who works with the Cassini mission, said in
a statement.
The new
images are from Cassini, the probe that has observed Saturn since 2004. In that
time Cassini has peered through Titan's cloud cover and at the clouds
themselves. In a renewed effort this year, the probe has gathered a new wealth
of information about the moon in six flybys since February 7. The next flyby is
scheduled for June 6, the Jet Propulsion Laboratory in Pasadena, Calif. reported.
Clouds
gather densely over the moon's southern hemisphere during its summer, and
Cassini has shown that the cloudy skies persist at least into the early fall. They
are expected to clear by August.
"It looks
like Indian summer on Earth, even if the mechanisms are radically different on
Titan," Rodriguez said. He revised Titan's early Autumn forecast,
predicting warmer and wetter weather than what the models have called for.
Warm is a
subjective term on Titan, where the average temperature is -290 degrees
Fahrenheit (-179 degrees Celsius). One measure of the cold there is its
volcanoes. While those on Earth spew molten rock, liquid water streams from
Titan's volcanoes.
In spite of
the brisk weather, Titan, is one of the most Earth-like worlds scientists have
found to date, NASA reports. It has a thick atmosphere and the right chemistry
to support some forms of life. It actually resembles a frozen version of Earth,
several billion years before organisms here began pumping oxygen into our
atmosphere.
Cassini has revealed a surface carved by rivers and lakes of liquid ethane and
methane (the main component of natural gas). The liquids evaporate and condense
in the atmosphere like water does here on Earth. Also like Earth's water, the
ethane and methane form
clouds and rain from Titan's sky.
In this
year's series of flybys, Cassini is monitoring Titan's atmosphere and surface
for signs of seasonal change. And NASA scientists say they await new data that
could confirm the presence of a liquid
ocean beneath the moon's surface.
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