well, is that possible to hit the speed of sound? i mean at 23 miles above the earths surface, maybe you could hit 768 mph but as you get closer and closer to the earth, you won't be able to.
so lets say, at 23 miles, there was a small enough amount of friction to be able to hit the speed of sound, but at 20 miles, there was just over the amount of friction needed to hit the speed of sound. so he would have 3 miles to hit 768 mph. but then, there is much less gravitational pull up at 23 miles, so therefor it would be even harder to hit 768 mph because you wouldnt be pulled down as hard.
im sure they have all the real math behind this and figured out that its possible, i just think its kinda crazy
what if he lights on fire on reentry?!?! hehe