Researchers at Fraunhofer Institute for High-Speed Dynamics in Germany are experimenting with how space probes could be used to deflect hazardous asteroids. They suggest impacting the asteroid with the probe at high speeds. The probe would transfer it’s own momentum to the asteroid; in addition the recoil of detached material from the crater would act as a turbocharger on the deviation of the asteroid. The impact of the probe would only change the speed of the asteroid by just a few centimeters per second but researchers say that’s enough to deflect its course significantly over a longer period. That means we need to attack years ahead of time. They determined this in simulations performed by attaching materials with asteroid-like properties to a pendulum and firing aluminum projectiles at them.