Venus
Impact Craters On Venus
Venus' atmosphere protects the surface from smaller objects that would otherwise impact the surface if the atmosphere were thinner. Smaller objects, especially those under 0.6 mi (1 km) in diameter are largely broken up in the atmosphere and do not directly impact the surface. For this reason and due to Venus' high volcanic resurfacing rate, rather few impact craters on Venus are known (less than 1000). Impact craters on Venus are frequently attended by flows of impact ejecta that look much like lava flows. This is due to the effect of the thick atmosphere on ejecta behavior during impact. Meade Patera is the largest impact crater basin on Venus at 174 mi (280 km) in diameter. There are only six known multi-ring impact basins on Venus, of which Meade is one. There are also large "splotches" (radar bright spots) about 6–44 mi (10–70 km) in diameter thought to be due to the effect of near-surface atmospheric detonation of incoming objects.
Additional topics
Science EncyclopediaScience & Philosophy: Two-envelope paradox to VenusVenus - Basic Properties, The Rotation Rate Of Venus, Venusian Surface Detail, Venusian Surface Processes, Venusian Internal Structure