747-sized asteroid skimmed by Earth, and scientists didn't see it coming

https://en.wikipedia.org/wiki/Air_burst

It was coming at us from the direction of the sun at 85,748 km/h. Didn’t even see it until it had passed us. About 3x the size of the one that hit Russia, so probably would have been a pretty big whack.

So what else is coming at us from the direction of the sun?

Almost everything.

Seriously. The Sun supplies us with a steady and strong stream of particles.

It wouldn't be catastrophic:

http://down2earth.eu/impact_calculator/input.html?lang=en

But we haven't figured out detection, we have about 1% chance to detect a larger one currently, depending on several parameters.