text:  too close for comfort for most folks that are thinking about the size of this asteroid. What happens if it does hit Earth? That's a good question. That's what was everybody's discussion back in 2004 is what if. Of course, there's certain scales that NASA has come up with and the scientific community, astrophysicists, that allow for us to say, okay, if it's this big, it'll have this much effect on the planet.