Thirty years ago, NASA's Mariner 10 spacecraft made the first of three passes by Mercury, sending back intriguing images of the planet's battered terrain. NASA will launch the world's second probe to Mercury - named MESSENGER - this summer. This image of the crater was taken on the first flyby. Note the central peak. North is up. (Mariner 10, Atlas of Mercury, Fig. 3-2) This crater (98 km diameter) illustrates the narrow hummocky rim facies, radial ridges, and surrounding extensive field of secondary craters. The well-developed interior terraces and central peaks are typical for mercurian craters in this size range. Note that the smaller craters in the foreground (25-km diameter) also are terraced. This image(FDS 80)was taken during the spacecraft's first encounter with Mercury. The Mariner 10 mission, managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, explored Venus in February 1974 on the way to three encounters with Mercury-in March and September 1974 and in March 1975. The spacecraft took more than 7,000 photos of Mercury, Venus, the Earth and the Moon. *Image Credi*: NASA
