PUBLIC INFORMATION OFFICE
JET PROPULSION LABORATORY
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PHOTO CAPTION          (TOP)                     August 29, 1989
                                                 P-34764C
                                                 Voyager 2-N77
 
Voyager 2 obtained this high-resolution color image of Neptune's
large satellite Triton during its close flyby on Aug. 25, 1989.
Approximately a dozen individual images were combined to produce
this comprehensive view of the Neptune-facing hemisphere of
Triton. Fine detail is provided by high-resolution, clear-filter
images, with color information added from lower-resolution
frames. The large south polar cap at the bottom of the image is
highly reflective and slightly pink in color; it may consist of
a slowly evaporating layer of nitrogen ice deposited during the
previous winter. From the ragged edge of the polar cap northward
the satellite's face is generally darker and redder in color.
This coloring may be produced by the action of ultraviolet light
and magnetospheric radiation upon methane in the atmosphere and
surface. Running across this darker region, approximately
parallel to the edge of the polar cap, is a band of brighter
white material that is almost bluish in color. The underlying
topography in this bright band is similar, however, to that in
the darker, redder regions surrounding it. The Voyager Mission
is conducted by JPL for NASA's Office of Space Science and
Applications.