PUBLIC INFORMATION OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011

PHOTO CAPTION

                                           Magellan
                                           P-38724 MGN72
                                           September 27, 1991

A portion of western Eistla Regio is displayed in this
three-dimensional perspective view of the surface of Venus. The
viewpoint is located 1,100 kilometers (682 miles) northeast of
Gula Mons at an elevation of 7.5 kilometers (4.6 miles). Lava
flows extend for hundreds of kilometers across the fractured
plains shown in the foreground to the base of Gula Mons. The
viewpoint is to the southwest with Gula Mons appearing at the
left just below the horizon. Gula Mons, a 3 kilometers (1.8
miles) high volcano, is located at approximately 22 degrees north
latitude, 359 degrees east longitude. Sif Mons, a volcano with a
diameter of 300 kilometers (180 miles) and a height of 2
kilometers (l.2 miles), appears to the right of Gula Mons. The
distance between Sif Mons and Gula Mons is approximately 730
kilometers (453 miles). Magellan synthetic aperture radar data is
combined with radar altimetry to develop a three-dimensional map
of the surface. Ray tracing -- rays as if from a light source are
cast in a computer to intersect the surface -- simulate a
perspective view. Simulated color and a digital elevation map
developed by Randy Kirk of the U.S. Geological Survey, are used
to enhance small scale structure. The simulated hues are based on
color images recorded by the Soviet Venera 13 and 14 spacecraft.
The image was produced at the JPL Multimission Image Processing
Laboratory by Eric De Jong, Jeff Hall and Myche McAuley, and is a
single frame from a video released at a March 5, 1991, JPL news
conference.