A NASA astronaut aboard the International Space Station (ISS) reported hearing an unusual noise from the Boeing Starliner spacecraft on Saturday, just days before its scheduled return to Earth on autopilot.
Astronaut Butch Wilmore contacted Mission Control at Johnson Space Center in Houston to inquire about the noise.
During their communication, Wilmore played the sound over the radio, describing it as a pulsating noise similar to a sonar ping.
Mission Control acknowledged the sound and informed Wilmore that they would investigate and update him. Wilmore clarified that the noise was coming from a speaker inside the Starliner.
The strange sound was initially reported by Ars Technica, with a recording shared by Michigan-based meteorologist Rob Dale.
The Starliner is set to undock from the ISS and attempt an autopilot landing in the New Mexico desert.
NASA has delayed the return of Wilmore and Suni Williams until February, citing safety concerns after thruster failures and helium leaks.
Originally planned for early June, the mission has faced multiple setbacks.
Boeing had hoped this first crewed mission would restore confidence in the Starliner program, which has suffered from years of delays and increased costs.