The colossal outpouring of lava thought to have almost totally resurfaced Venus 500 million years ago never happened, a new study says. If correct, it means that a much longer record of Venus’s history is preserved on the planet’s surface. Planetary scientists estimated the age of Venus’s surface after studying radar mapping data from NASA’s Magellan spacecraft, which operated in the early 1990s. Assuming Venus was exposed to the same rain of asteroids and comets that the other planets experienced, they expected Magellan would spot about 5000 craters on the planet’s surface. But they found only about 1000, suggesting that the planet’s surface is actually very young – perhaps 500 million to 1 billion years old. And those craters appear remarkably well preserved, unaltered by erosion or other geological processes. The most popular explanation is that a brief but enormous episode of volcanism blanketed most of the planet in a layer of lava 1 to 3 kilometres deep – thick enough to bury all of the craters made before that time. Now, a new analysis of Magellan data suggests that such a deep layer of solidified lava cannot be present on the surface, casting doubt on the „catastrophic resurfacing“ hypothesis.

Abstract: Venus was not catastrophically resurfaced