Autonomous laser spacecraft for the purpose of redirecting asteroid trajectory.
A 300 KWH laser heating the rock face of the asteroid target produces about 400 tons per second of thrust. Deep space interception of the asteroid provides enough time to shift the trajectory into a solar intercept course. This mission eliminates the threat permanently.
Advanced modeling can predict the exact position and burn time necessary to achieve this mission. Several lasers can be used to generate sufficient lateral force to move the object.
The advantages are that the asteroid provides the fuel source for the mission. Superheated rock gas is excelled from the asteroids surface, essentially simulating a rocket motor mounted on the asteroid. An actual rocket motor is impractical due to the fuel required. Invoking newton’s law of equal and opposite reaction in space, it can be computed how long the craft must operate to achieve a satisfactory course correction avoiding an extinction level event. The craft can be reused when the mission is accomplished. Several more lasers or more craft can be used if necessary for largest objects.