Why do rocks on other solar system bodies that have an atmosphere seem to be flat?

Question

Images taken by landers on Titan and Venus and Mars show landscapes where rocks, to me at least, are surprisingly flat. Being used to walking around in forests with roundish meter sized boulders, I'd be very surprised to find myself in a landscape of flat rocks. Their atmospheric density range between about 100 times, half and 1/100th of Earth's atmosphere. So that can't be the main explanation. Actually, I think that the landscape of the Moon is more Earth like than that of the atmospheric worlds out there. Is this my impression of "flatness" a real phenomenon, and if so, why and how?

Answer 1

Well, in the absence of water from oceans, there is no moving around of the flat rocks to make them rounder. For example, if you look at a stream that has a lot of water flow, the rocks often at the bottom of the stream are rounded, due to erosion. But, in still water, there is not many collisions that round off the sharp edges.

Likewise on this moons or planets, the absence of water causing flow leaves the rocks jagged, with flat sides, no rounding off can occur.