This will be a reality one day, it's not a matter of IF, but a matter of WHEN! via Live Science If a giant object looks like it's going to slam into Earth, humanity has a few options: Hammer it with a spacecraft hard enough to knock it off course, blast it with nuclear weapons, tug on it with a gravity tractor, or even slow it down using concentrated sunlight. We'll have to decide whether to visit it with a scout mission first, or launch a full-scale attack immediately. Those are a lot of decisions to make under existential duress, which is why a team of MIT researchers have come up with a guide, published February in the journal Acta Astronautica, to help future asteroid deflectors. In movies, an incoming asteroid is usually a very last-minute shock: a big, deadly rock hurtling right toward Earth like a bullet out of the darkness, with only weeks or days between its discovery and its projected impact. That is a real threat, according to an April 2019 presentation by NASA's Office of