I got a new Hood
& paint job four months ago and have some now. It's from small pieces of debris striking your car especially rocks, and especially on the highway. Keep away from cars with exceptionally big tires and semis, cause they like to kick up rocks really high. No way you can prevent them unless you put a bra on your car.
I don't even know if they make them for the Celica cause I've yet to see them, but they won't protect the whole Hood
and they are FUGLY.
Everyone gets them, but you can't really see them unless you look for them. Buy some touch up paint from a Toyota dealership. Here's a ***LINK***
to how you can fix them yourself if they bother you.