Asking a reaaallyy shy guy to formal (prom)?!? HELP!?

[Brigitte88]

Here's a list of all the positive and negative points:

1. He has been in one of my class for 2 years but basically never talks to me
2. His friends now sit with the guys in my group of friends, and he has talked to me when they are there, but not when he's by himself
3. He's reeeeaaallly shy :l He always stands away from everyone else, so I'm worried if we went together it would just be awkward
4. He and his friend are joining my group in out car ride to the formal (:
5. His other friends have dates, but he doesn't, so I though maybe he would like to have one
6. I want to ask him but I'm extremely scared of rejection, and I thought because he's so shy he might not want the pressure of having a date and hence, will say no
7. I don't know how to ask him! It would be over facebook though cause he's so shy in person
8. If he says no I'm worried it's going to be uber awkward at school...

WHAT SHOULD I DO!? ):