I'm watching "Killer Asteroids" and while the scientists being interviewed give their ideas for destruction and/or deflection and I wondered:

Why not create a weapon/device that fires an energy beam/blast at the asteroid that could simulate the earth's atmospheric friction and just burn it until it disintegrates or explodes into nothingness???

Interesting idea ... but the heat is caused by friction between the atmosphere and the extreme speed of the asteroid ... I don't think we have enough power available as a species to actually burn the entire surface of the target ... maybe burn small sections but no way we could vaporize the entire surface. And if you widen the field of the beam to encompass the entire surface; you would no longer have enough power to burn it at all. I think you might have a little more luck affecting comets ... Asteroids are mostly composed of nickle and iron (we think ;-)