Approximately 900 impact craters are known on Venus. Most were identified through radar mapping because Venus’s permanent, opaque cloud cover hides its surface from ordinary visible-light observation.
NASA’s Magellan spacecraft provided the most complete global radar survey, mapping nearly the entire planet and revealing close to 900 impact craters. Earlier radar observations from Earth and the Venera 15 and Venera 16 spacecraft had identified far fewer probable crater features.
Venus has fewer craters than the Moon, Mars, or Mercury. Its dense carbon-dioxide atmosphere burns up or fragments many smaller incoming meteoroids before they reach the ground. As a result, Venus has very few impact craters smaller than about 30 kilometers across, and Magellan found no confirmed craters smaller than roughly 2 kilometers.
The distribution of the craters also tells scientists about Venus’s history. They are spread relatively uniformly across the planet, suggesting that much of the surface was resurfaced by widespread volcanic activity roughly 500 million years ago. The crater count therefore helps estimate Venus’s geological age as well as its impact history.