Cause,
a quick glance at mars reveals that its surface has been repeatedly
pounded by asteroids, leaving thousands of craters behind. in fact, research-
recently counted 635,000 craters on mars that were a kilometer or larger in
ameter! in contrast, scientists know of about 180 such craters on earth
why does mars have so many more craters than earth? scientists report
three main reasons why earth has such a small number of craters on its
surface. first, earth has a thick atmosphere. (the atmosphere of mars is less
than 1% the thickness of earth's atmosphere.) because of this atmosphere, a
lot of erosion occurs on earth. wind, water, and plants wear down the ground,
eventually erasing any evidence of a once-existing crater. the second reason
is tectonics. the earth's crust is covered in plates that move. when plates
shift, craters can become invisible. the third reason for the small number of
craters on earth is the presence of volcanoes volcanic flow has certainly filled
in many craters over billions of years. these three features erase evidence of
asteroids that once impacted earth