Question: Given that asteroids from mars are found on earth, would asteroids from earth be found on mars?

Kamal Bhattacharya answered on 16 Jan 2017:

It’s a great question. The answer is yes. Think of the big meteoroid that hit the earth 65m years ago and extinguished the dinosaurs. 10km in diameter and trillion tons of weight. That must have created billions of tons worth of rocks flying off earth into space. Scientists have calculated where the material could have ended up. So one result I saw is that Europa, one of the moons around Jupiter, must have gotten hit by rocks from the earth as much as our very own moon. So think about it. It’s not just rocks, its water, life, that went into space. What I don’t know is if we have found remnants of these rocks in human moon expeditions.