On January 27, 1967 a short circuit in NASA’s Apollo 1 command module sparked a fire fueled by the pure oxygen atmosphere resulting in the death of all three astronauts aboard. Commander Virgil Grissom and Pilots Edward White and Roger Chaffee were conducting an unfueled test run during the incident. The infographic below details the incident and how it changed NASA’s design safety. The incident is now commemorated every year on January 27 along with the Challenger and Columbia disasters. It was the second space-related incident involving flammability of a pure oxygen atmosphere. The first occurred on March 23 1961 in the USSR when Valentin Bondarenko died of burns following a fire in a low pressure chamber. Details of this incident did not reach the west until 1986.