MEMPHIS, Tenn. (WMC) - Scientists know of about 180 craters from meteors that have made it to Earth. However, the Moon’s surface is covered with visible craters from meteors. So why does the Moon, which is much smaller than Earth, have so many more?
This difference is due to the processes on Earth, such as erosion, tectonic movement of plates and volcano flows. Over Earth’s 4.5 billion year history, there are probably many more meteor hits that were gradually covered up over the years.
Since the moon doesn’t have an atmosphere, it has no wind or erosion to erase the craters. The moon initially had volcanoes and tectonic movement, so some of the earlier craters were likely covered up. However, these processes have not occurred for about 3 billion years.
This means that any hit from a meteor will always be visible on the moon because nothing erases it away. According to NASA, even the footprints from astronauts in 1971 are still on the moon today.