* Astronomy

Soviet N-1 rocket explosion in 1969.

  Vehicle serial number 5L - Zond L1S-2 for Moon flyby - At liftoff a loose bolt was ingested into a fuel pump, which failed. After detecting the inoperative fuel pump, the automatic engine control shut off 29 of 30 engines, which caused the rocket to stall. The rocket exploded 23 seconds after shutting off the engines, destroying the rocket and launch tower in the biggest explosion in the history of rocketry and also the largest manmade non-nuclear explosion ever (nearly 7 kilotons of TNT equivalent.) 
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