The Knocking Heard by China's First Astronaut
Alone in orbit, China's first astronaut heard a knocking on his spacecraft, like someone tapping on an iron bucket with a wooden hammer.
What was reported
In October 2003, Yang Liwei became the first person China sent into space, orbiting alone in the Shenzhou 5 capsule for 21 hours. During the flight, he later said, he heard a sudden knocking sound, like someone tapping on the outside of the spacecraft with a wooden hammer.
He looked out of the window and saw nothing. The sound came and went, and astronauts on later Shenzhou missions said they had heard it too.
Explanations offered
The cause has never been identified. Engineers have suggested that the spacecraft's metal skin and fittings were expanding and contracting as it passed between sunlight and shadow, which can make a structure creak and knock. Yang Liwei himself said he never found out what it was.
- When
- 15–16 October 2003
- Where
- In orbit over China, aboard Shenzhou 5
- Witnesses
- Astronaut Yang Liwei, and crews of later missions
- Status
- Unexplained
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