Final answer:
The Moon has more craters than the Earth due to the lack of active geology on the Moon and the constant renewal of Earth's crust through plate tectonics and volcanism. The Moon is older and has had more opportunities for impacts, and its composition differs from that of the Earth.
Step-by-step explanation:
The reason there are more craters on the Moon than on Earth is because the Moon is primarily impacted by interplanetary debris such as asteroids and comets, whereas Earth's craters are destroyed by its active geology. This is due to the processes of plate tectonics and volcanism on Earth, which constantly renew its crust and slowly erase evidence of past impacts.
Additionally, the Moon is older than the Earth and has had more opportunities for impacts to occur over its longer history. The heavily cratered highlands on the Moon are made of rocks more than 4 billion years old, while the darker volcanic plains of the maria were erupted between 3.3 and 3.8 billion years ago.
Moreover, the Earth and Moon are made of different materials. The Moon is severely depleted in metals and volatile materials, and is made almost entirely of silicates like those in Earth's mantle and crust. This difference in composition can also contribute to the differences in the number of craters between the two bodies.