I don't think this is exactly the closest asteroid crossing ever recorded. Back around 1970, an asteroid variously estimated to be from 80 feet to 80 meters in diamater* actually entered the Earth's atmosphere at a shallow angle. If flew from somewhere around Arizona across several states and exited the atmosphere up around Canada. I've seen both home movies and still pictures of the event. I'd have to say that was the closest event ever recorded without it actually hitting or burning up in the atmosphere.

* According to estimates from people like Eugene Shoemaker, an object that size would've released from 1 to 10 megatons of energy had it hit the surface.