If, as your tone implies, you believe that every teenager knows everything and it's not possible for some of them to have not heard or these things, then you must in fact be a teenager yourself.
I don't think it's unreasonable to be surprised that a teenager (at least, an American teenager) isn't aware of such a thing. They've managed to get through school without once being shown a photo of the space shuttle? Not one blurb? Never seen it in a TV commercial? Photograph?
If, as your tone implies, you believe that every teenager knows everything and it's not possible for some of them to have not heard or these things, then you must in fact be a teenager yourself.