this was followed at 73.124 seconds by the appearance of the suggesting the structural failure. , weber wasonds later observed that the inner tank. tankative of the oxygen failing. with normal loads being induced by the formal attach point or from the propulsive forces created by the aft bulkhead daily. probably both. within milliseconds liquid -- liquid oxygen was seen streaming along the external tank. at 73.191 seconds a flash was observed that was immediately followed by the start -- the start of total vehicle breakup. the next 100 milliseconds, additional flashes occurred in the forward attach areas. as it broke up, the released fluids broke open rapidly, releasing vapors and fluids that .ad them -- had embedded debris no shockwave or other evidence of a violent explosion was detected in the imagery. and it doestion give the crowd the appearance of . firewall we are in automatic shutdown mode as a result of reduced propellant pressures. the last till on a tree was received after launch. essentially obscured by the vapor cloud, hundreds of fragments were noted exiting the cloud. those ident