Watch History Undercover online: Episode 1 Secrets of Soviet Space Disasters

It was a centerpiece of the Cold War. The space race between the U.S.S.R. and the U.S.A. resulted in some of the most significant scientific and engineering advances in human history. But it was also marred by tragedy. And while the stories of American mishaps--such as the fire that claimed the lives of three Apollo astronauts in 1967--are well documented, the failures of the Soviet space program remained closely guarded secrets until only recently. Filled with rare, never-before-seen footage from Soviet archives and interviews with insiders like Ronald Sagdeev, Mikhail Gorbachev's science advisor, SECRETS OF SOVIET SPACE DISASTERS brings these long-hidden stories to light. See how personal rivalries, shifting political alliances and bureaucratic bungling led to the more than 150 deaths as well as the eventual failure of the Soviet space program itself.

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