Lasers in the sky (with asteroids)
Today lasers are routinely flown on space and airborne platforms for scientific, military and telecommunication applications. While they make nice special effects in action and sci-fi movies, there are physical boundaries that guide the use of lasers in space and in surface to air/space scenarios. 'SDI' might not be straight forward, but intercepting airborne vehicles or laser based communication to submerged submarines is no longer science fiction. But can we use it for space travel? Lets see.