Owing to the thick clouds we know little of the surface of Venus. Reference has already been made to the craters observed by radar. There is a scarcity of small craters; this is to be expected because the dense atmosphere would burn up the smaller meteoroids which would otherwise produce these craters. Venus is a very flat planet with few features more than a kilometer in height but again the hot, dense corrosive atmosphere may have been responsible by causing more rapid erosion than on Mars. This is not certain, for the winds at the surface may not be strong enough to pick up the dust which, by sandblasting, is thought to be the major cause of erosion on Mars.

Spacecraft have softlanded on Venus and sent television pictures of the nearby surface back to Earth. These showed a mixture of smooth rounded stones and angular rock fragments typically 30 to 40 cm across which appear to form a geologically young landscape. By contrast, the other spacecraft landed in a smoother area with large flat boulders that is apparently geologically older. This shows that erosion does occur on Venus even though there is no liquid water and possibly insignificant] windborne dust.

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