The Pings Heard on Starliner
An astronaut aboard the space station radioed Mission Control about a strange sound coming from a spacecraft docked outside: a pulsing ping, like sonar.
What was reported
In August 2024, Boeing's Starliner capsule was docked to the International Space Station after a troubled first crewed flight. Astronaut Butch Wilmore called Mission Control in Houston to report an odd noise coming from a speaker inside it: a rhythmic pulsing, like a submarine's sonar ping.
He held his microphone up to the speaker so Houston could hear. The recording spread online, and people asked whether something was knocking from outside.
Explanations offered
NASA found it was audio feedback, caused by the way the space station and Starliner's audio systems were connected. It was harmless. Starliner returned to Earth uncrewed a week later.
- When
- 31 August 2024
- Where
- In orbit, docked to the International Space Station
- Witnesses
- An astronaut on the space station, and Mission Control in Houston
- Status
- Explained
Famous cases are real, widely reported events. Each file sets out what witnesses said and the explanations that have been offered, without taking a side.