[Poohbah]

I was thinking a series of direct surface impacts, 24-hour intervals.

Doesn't change the numbers any.

Asteroids--even itty-bitty ones--are way too damn big for just a few nukes to do anything.

Hit that thing three or four times, it will shatter and then the last blast will scatter the fragments.

Actually, it wouldn't. There's no air to conduct the blast wave, which means that only radiation pressure will move the rocks--and that's not much of your total energy budget.

[Williams]

Smarty pants.

[inquest]

There's no air to conduct the blast wave, which means that only radiation pressure will move the rocks

Vaporized rock should help, too.