These mosaics of the south pole of Saturn's moon Titan, made from images
taken almost one year apart, show changes in dark areas that may be lakes
filled by seasonal rains of liquid hydrocarbons.
The images on the left (unlabeled at top and labeled at bottom) were
acquired July 3, 2004. Those on the right were taken June 6, 2005. In the
2005 images, new dark areas are visible and have been circled in the
labeled version. The very bright features are clouds in the lower
atmosphere (the troposphere). Titan's clouds behave similarly to those on
Earth, changing rapidly on timescales of hours and appearing in different
places from day to day. During the year that elapsed between these two
observations, clouds were frequently observed at Titan's south pole by
observers on Earth and by Cassini's imaging science subsystem (see PIA06124).
It is likely that rain from a large storm created the new dark areas that
were observed in June 2005. Some features, such as Ontario Lacus, show
differences in brightness between the two observations that are the result
of differences in illumination between the two observations. These mosaics
use images taken in infrared light at a wavelength of 938 nanometers. The
images have been oriented with the south pole in the center (black cross)
and the 0 degree meridian toward the top. Image resolutions are several
kilometers (several miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European
Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory,
a division of the California Institute of Technology in Pasadena, manages
the mission for NASA's Science Mission Directorate, Washington, D.C. The
Cassini orbiter and its two onboard cameras were designed, developed and
assembled at JPL. The imaging operations center is based at the Space
Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit
http://saturn.jpl.nasa.gov/. The Cassini imaging team
homepage is at http://ciclops.org.