@Oct -- if you read the fine print...the light particles require 20 years to have the necessary affect. It's not one of those "Oh shit! there's an asteroid gonna kill us next week..." plans. It's more like this scenario...
"Hey bob...there an asteroid drifting about Saturn headed this way. We'll be retired by then....hey, give me one of those smokes....Oh...anyway...<cough cough...damned emphysema....> So what do you want to do about this asteroid?"
"You know those fuckers didn't give me raise? How about you?"
"No...but stay on topic Bob. Asteroid...doomsday...all that shit. They'll need a plan?"
"Plan? <cough cough...nothin' like smokin' a good red man in the lab...Pisses of that sex-retary, you know?> Plan, huh? We should probably quit these things, you know? <cough cough..> Anyway, I'll give those fuckers a plan. 50,000 tons of paintballs, We'll tell 'em the sun will push it away if you paint it white. Those assholes will believe anything...after all, they pay us (barely, motherfuckers...) to come up with these brilliant ideas. I'll laugh my ass off if they but this...wanna make a bet?"
"Paintballs? Haaa ha ha! that's golden, man. You write that up, I'll order the pizza. $2 says they don't buy it."
"You're on..."