Two Nasa astronauts arrived at the International Space Station on Thursday evening aboard the Boeing Starliner spacecraft.
The much-delayed launch took place on Wednesday from a Florida spaceport and is part of Nasa’s efforts to secure another “taxi ride” to the orbiting laboratory, in addition to SpaceX.
Astronauts Butch Wilmore and Suni Williams, who reached the station at 9.35pm GST and will stay there for about a week, are testing the spacecraft to ensure it is ready for commercial operations.
"Docking confirmed! Boeing's Starliner docked to the forward-facing port of the International Space Station's Harmony module at 1:34pm ET (1734 UTC). Nasa astronauts Butch Wilmore and Suni Williams will soon make their way into the orbital laboratory, where they'll spend about a week," Nasa posted on X.
A mission years in the making
Nasa awarded Boeing a $4.2 billion contract under its Commercial Crew Programme, which aims to encourage companies to develop spacecraft that can deliver astronauts into space.
Boeing had been trying to develop the Starliner capsule for nearly a decade, but the launch was plagued with delays because of technical issues.
During this mission, Boeing will monitor a series of automatic spacecraft manoeuvres from its mission control centre in Houston, while Nasa will oversee space station operations throughout the flight.
The astronauts will help verify the spacecraft is performing as intended by testing the environmental control system, the displays and control system and by manoeuvring the thrusters.
Seasoned space travellers
Ms Williams, a retired Navy captain, has logged 322 days in space and completed seven spacewalks totalling 50 hours and 40 minutes.
Mr Wilmore is a US Navy captain who has spent 178 days in space. He was selected as an astronaut in 2000.
Yesterday's launch was the third attempt that Boeing and Nasa have made in under a month to send the astronauts to the station.
The original launch date of May 6 was cancelled only hours before lift-off due to a faulty oxygen relief valve in the Atlas V rocket's Centaur upper stage.
The investigation and replacement of the valve pushed the launch back to May 17, and then further delays occurred after a helium leak was detected in the Starliner's service module.
After an investigation, engineers decided the leak was not significant enough to delay the launch any further.
But two more helium leaks occurred on the craft as it was en route to the space station.
Despite the technical issue, mission control said the capsule was ready for docking and that they were monitoring the leak.
Boeing completed an unmanned test flight in 2022 when a Starliner capsule docked on the ISS and returned to Earth.
The launch came after an unsuccessful test flight in 2019, in which the craft failed to reach the station due to a software glitch.
Elon Musk's SpaceX, also part of the Commercial Crew Programme, has dominated the lucrative business and delivered eight crews to the ISS on behalf of Nasa since 2020.
