Chinese astronaut Yang Liwei made a controversial statement during an interview, according to the Xinhua News Agency. According to him, during his stay at the International Space Station (ISS) in 2003, he clearly heard some sounds of unexplained origin.
The astronaut described these sounds: 'The sound appeared for no reason and was repeated more than once. I would not say that it came from outside, but it sounded as if someone was knocking on the ISS, the sound was like striking a wooden hammer on a bucket. '
During the spacewalk, Yang tried to check what it could be, but was left at a loss since the source of the noise could not be found.
