Question: Why do asteroids come to earth and how often?

Joanna Barstow answered on 20 Nov 2019:

Asteroids come to Earth because there are lots of chunks of rock in various orbital paths around the sun. Sometimes those paths might intersect the path of the Earth, and then the asteroid will collide. It is very rare for something asteroid sized to hit the Earth – the last one we are aware of was the impact that made the dinosaurs extinct. Meteorites often enter the Earth’s atmosphere but these are much smaller.