As the Magellan spacecraft orbits Venus its radar instruments are penetrating the thick clouds that prevent optical cameras from photographing the planet's surface. A portion of the Venusian surface was unveiled at a meeting of the American Geophysical Union in San Francisco in early December when mission scientists presented radar images of the planet and discussed their first tentative interpretations of what those images reveal. The images on these pages represent only a few of the strikingly diverse types of terrain that have been seen so far, with the mission having mapped only 15&percent; of the surface.