I wonder if they can pull that off.
How about Mach 7-10? :D
LOOK :P
Clicked on your link. Ironic to see the B-52 (as mothership to the Pegasus) and its possible successor, the X-43A, on the same NASA page.
Can't help but wonder about weapon targeting and dynamics (release and flight control) at Mach 7. Rear ejection a la A-5 Vigilante/reentry heat shielding/offboard terminal guidance? Hmmm...