We have this activity in Physics. This is a scenario: An asteroid is found near the earth's orbit and if the..?

Earth comes close to it, the earth's gravitational pull may pull the asteroid towards the earth, destroying it. We are playing the role of astronauts and physicists and we are supposed to move the asteroid with two large metal . The problem is, how much should the force be and in what direction should it be? I was thinking something like two parallel forces, but I have no idea about the force's magnitude. Thank you so much!