Hey slip
I learned almost everything I know about airflow listening, not reading, so what follows is highly suspect. First my brother was present during that pass and swears it was subsonic.
Everything about airflow comes from area ruling, as suggested above. And Bernoulli and his "inviscid flow". There is a very substantial eddy at wing root and fuselage, it can be impenetrable dependent on available thrust. When the F-102 was launched as a supersonic fighter, it disappointed. Something was keeping it from Mach 1 despite all the calculations. Turns out a "slice" through the A/C at this barrier of air was representative of more cross section than 24 very obese opera singers. What the Tunnel taught the builders of the F-106 (the new 102), was to pinch the body at the wing root (coke bottle). This allowed the "dam" of viscid air to reduce and allow the supersonic region of airflow past.
Back to the Hornet. The Wave you see is most likely the "tail event" or the first of two potential "Booms" passing through Mach1. The larger pic would likely show the "nose event" wave or #2 Boom. When there are no shock waves of note attached to A/C it is assuredly smokin' nuttin'.
Bernoulli's work suggests that air in an infinite enclosure is "Incompressible" below a speed of 267(?) knots. Above that speed and it becomes compressible, both against itself and solids (wings, tails,etc). I think it is the leading edge of this "packed" air that slows the faster air down and creates those beautiful cones.
If this is accurate, It is due to memory of Hoser and Coon talking after several beers. If it's not I'll track them down and wring their necks.
Airfoil