Computer elevates Venus to new heights.

Computer elevates Venus to new heights

This view of cloud-covered Venus, released last week by NASA, reveals the hills and valleys of the western Ishtar Terra highland in the planet's northern hemisphere. Scientists created the image from selected radar surface scans made by the Magellan spacecraft between Sept. 15 and Oct. 15, and used computer processing to incorporate surface-elevation measurements made in 1979 by the radar-equipped Pioneer Venus spacecraft. This provides a three-dimensional view of Venus' terrain.

To help planetary geologists spot elevations and depressions, vertical features have been highlighted through computer coloration, and their dimensions have been visually exaggerated 10-fold compared with horizontal features. Black stripes represent gaps in Magellan's data.

The peak indicated by the arrow rises fewer than 500 meters, with a base measuring about 30 kilometers in diameter. This unnamed hill, possibly an active or extinct volcano, does not show up in straight-down views, says R. Stephen Saunders, Magellan project scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif.

The high mountain on the horizon rises about 2 kilometers above its surroundings and anchors the near end of a mountain chain called Danu Montes, which extends about 1,000 kilometers beyond the horizon, Saunders says.