A Chinese astronaut has reported hearing a strange “knocking” sound in space – and no one is quite sure what it is. The rest of this article is behind a paywall. Please sign in or subscribe to access ...

In 2003, China’s first astronaut reported hearing an unexplained “knocking” sound while in space, a noise that eerily resembled someone knocking from outside. Despite more than two decades of ...

The mysterious knocking sounds heard beneath the Atlantic Ocean that gave false hope that the Titan submersible and its occupants could be rescued has been revealed in a haunting new audio clip. After ...

Q: My 2004 Porsche Cayenne has developed a knocking noise when accelerating. After reaching a speed of 40 mph or higher, it stops. The noise seems to be from underneath the vehicle about midway, sort ...