NASA documentary of the near-fatal Apollo 13 mission in 1970, including the onboard explosion on April 13 and efforts by the ground crew and flight crew to troubleshoot the malfunction and design and implement contingency procedures to bring the crippled spacecraft home. 

The Katyn massacre was a mass murder of thousands of Polish prisoners of war (primarily military officers), intellectuals, policemen, and other public servants by the Soviet NKVD. After 3 April, 1940, at least 22,436 POWs and prisoners were executed: 15,131 POWs (most or all of them from the three camps) and at least 7,305 prisoners in western

The Katyn massacre was a mass murder of thousands of Polish prisoners of war (primarily military officers), intellectuals, policemen, and other public servants by the Soviet NKVD, based on a proposal from Lavrentiy Beria to execute all members of the Polish Officer Corps. Dated March 5, 1940, this official document was then approved (signed) by