John Hopkins University, Applied Physics Laboratory. Launched at 0450 local time. Reached 88.5 km. 1 Flight 55. Maximum Speed - 5697 kph.
China conducts first thermonuclear bomb test.
Long March . Molniya 8K78M . Stage 4's engine 11D33 failed to ignite because the turbopump had not been cooled before ignition. Investigation of the upper atmosphere and outer space. Maximum Speed - 1051 kph.