Researchers are making the ultimate science-fiction weapon to deal with asteroids. A system called DE-STAR [DirectedEnergy System for Targeting of Asteroids and exploration], will use laser beams to interrupt and repel space rocks. This particular idea has been around for numerous years, but a new research paper is now offering it as a practical solution to protect against dangerous 'Near Earth Objects' (NEOs).
The system is the invention of UC Santa Barbara physicist Philip Lubin and Gary Hughes, a scientist and professor at California Polytechnic State University, San Luis Obispo. Another, relatively smaller system, is also being constructed, called DE-STARLITE. Scientists visualize this travelling along with the hazardous asteroid and slowly deflecting it over a longer period of time. Qicheng Zhang of the University of California, one of the authors of the project, told Astrowatch.net “Generally speaking, the technology is available today. The main problem with constructing a full DE-STAR is the essential scale to be effective.”
In a research paper issued this year in the journal Earth and Planetary Astrophysics, Zhang clarifies how lasers could move or vaporize an asteroid on a collision course with Planet Earth. According to him an orbital planetary defense system will be able heat asteroids to the point of vaporize.
According to Astrowatch.net if DE-STAR had a 330-feet-wide laser array, it could easily divert asteroids 330 feet in diameter from a distance of almost two million miles. A 20 kW kind of DE-STARLITE functioning for 15 years could deflect a 1,000ft asteroid at a distance of just 8,000 miles.
The DE-STAR system might be used for many other missions, like stopping the spin of a rotating asteroid and attaining relativistic propulsion.
You can readre about DE-STAR system in detail here.