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-45392
                                                    March 16, 1995

This hemispheric view of Venus, as revealed by  more than a decade 
of radar investigations culminating in the 1990-1994 Magellan 
mission, is centered at 90 degrees east longitude. The Magellan 
spacecraft imaged more than 98 percent of Venus at a resolution of 
about 100 meters; the effective resolution of this image is about 
3 kilometers. A mosaic of the Magellan images (most with 
illumination from the west) forms the image base. Gaps in the 
Magellan coverage were filled with images from the Earth-based 
Arecibo radar in a region centered roughly on 0 degrees latitude 
and longitude, and with a neutral tone elsewhere (primarily near 
the south pole). The composite image was processed to improve 
contrast and to emphasize small features, and was color-coded to 
represent elevation. Gaps in the elevation data from the Magellan 
radar altimeter were filled with altimetry from the Venera 
spacecraft and the U.S. Pioneer Venus missions. An Orthographic 
projection was used, simulating a distant view of one hemisphere 
of the planet. The Magellan mission was managed for NASA by the 
Jet Propulsion Laboratory (JPL), Pasadena, CA. Data processed by 
JPL, the Massachusetts Institute of Technology, Cambridge, MA, and 
the U.S. Geological Survey, Flagstaff, AZ.