A cracked solid propellant rocket motor would do it.
This ^^^
I had a friend that worked for Thiokol back in the day designing solid motor nozzles. He would tell me about solid motors and how they could fail.
I actually thought this is what happened when the Challenger accident happened but I later found out the SRBs used a different type of propellant compound than smaller missiles.
I'm thinking that the explosion shattered the propellant into eight chunks that created the eight white arcs shown in the photo.
IIRC, the solid-fuel rocket motor on a Standard missile burns its fuel from an inner open cylinder running up the center, out toward the casing. The outer skin of the motor is quite thin since the pressure is largely contained by the unburnt fuel.
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