I'd say it was pretty close, considering it's size and relative distances. Bit like having a bullet miss ya head by 2ft! Close enough to raise pulses.
Dunno if that's what'll kill us. I don't think we could realistically deal with one now. We can't even get to Mars or even the moon, never mind redirect of destroy a world killing asteroid/comet.
Couldn't we just fire a few nukes at one if it was on its way to hitting us?