Unfortunately, there have been a number of horrific disasters of the space program. Between the explosions of the Challenge and Columbia space shuttles and the tragic deaths of the Apollo 1 astronauts in America, and the explosion of the Vostok-2M rocket and the deaths of the Soyuz 11 cosmonauts for the USSR, history’s worst space disasters have left a black mark on the space program. WatchMojo counts down ten of the most devastating space flight disasters ever.