SpaceX mission docks successfully at ISS to retrieve stranded Nasa astronauts

The SpaceX crew that will bring back two astronauts stranded on the International Space Station docked with the orbiting laboratory on Sunday, according to a live stream of the mission.

The Falcon 9 rocket took off at 1:17pm from Cape Canaveral, Florida on Saturday, with the Crew-9 mission on a Dragon spacecraft making contact with the ISS at 5:30pm Sunday.

After docking was completed, the National Aeronautics and Space Administration's (Nasa) astronaut Nick Hague and Russian cosmonaut Alexander Gorbunov boarded the station just after 7pm, embracing their floating colleagues on the space station, AFP reported.

"What a fabulous day it was today," Nasa deputy administrator Pam Melroy said at a news conference.

When Hague and Gorbunov return from the space station in February, they will bring back two space veterans — Butch Wilmore and Suni Williams — whose stay on the ISS was prolonged for months due to problems with their Boeing-designed Starliner spacecraft.

The newly developed Starliner was making its first crewed flight when it delivered Wilmore and Williams to the ISS in June.

They were supposed to be there for only an eight-day stay, but after problems with the Starliner's propulsion system emerged during the flight there, Nasa was forced to weigh a radical change in plans.

After weeks of intensive tests on the Starliner's reliability, the space agency finally decided to return it to Earth without its crew, and to bring the two stranded astronauts back home on SpaceX's Crew-9 mission.

The Elon Musk-owned SpaceX has been flying regular missions every six months to allow the rotation of ISS crews. However, the launch of Crew-9 was postponed from mid-August to late September to give Nasa experts more time to evaluate the reliability of the Starliner and decide how to proceed.

It was then delayed a few more days by the destructive passage of Hurricane Helene, a powerful storm that roared into the opposite side of Florida on Thursday.

In total, Hague and Gorbunov will spend some five months on the ISS; Wilmore and Williams, eight months.

In all, Crew-9 will conduct some 200 scientific experiments.