Why are there annual meteor showers like the Leonids and Perseids?

Question

I understand that meteor showers are due to the Earth passing through the debris left by a comet, but shouldn’t the Earth clear out any lingering meteors after a few revolutions?

In: Planetary Science

Answer 1

The debris from the comets still orbit the Sun in the orbit that the comet had. So while the Earth do clear out a tunnel in the debris field these debris would have continued on their orbit and be well outside the Earth’s orbit when the Earth comes around to the same spot again. But more debris is coming inn from the outer solar system in the orbit of the comet and will impact the Earth.