Three American astronauts and a Russian cosmonaut are due to blast off Sunday night from Florida for a six-month mission on the International Space Station.
After an attempt was called off Saturday night due to strong winds, the SpaceX Falcon 9 rocket is due to lift the travelers into orbit at 10:53 pm (0353 GMT Monday) from the Kennedy Space Center.
If forced to abort before launch again, SpaceX will have another opportunity Monday night.
Endeavour, the capsule carrying the three men and one woman to orbit, has already been launched four times by Elon Musk’s SpaceX.
The company has been providing astronaut launch services for NASA since 2020 under the US space agency’s Commercial Crew Program, with rival contractor Boeing yet to finish its certification.
Matthew Dominick, leader of the Crew-8 mission, is making his first spaceflight, as is fellow American Jeanette Epps. It will also be the first time for Russian Alexander Grebenkin.
Michael Barratt, a physician, is making his third visit to the ISS. His first two were aboard space shuttles, which were discontinued in 2011.
Space remains a rare area of cooperation between the United States and Russia since its 2022 invasion of Ukraine.
The United States last month imposed fresh sanctions on 500 Russian targets, seeking also to exact a cost for the death of Russian opposition leader Alexei Navalny in an Arctic prison.
Seven people are currently aboard the ISS. After an overlap of a few days, four members of the current ISS crew — an American, a Dane and one person each from Japan and Russia — will return to Earth in their own capsule.
The refreshed crew will carry out experiments including using stem cells to create organoids (artificially grown masses of cells resembling organs) to study degenerative diseases, taking advantage of the microgravity environment to enable three-dimensional cell growth not possible on Earth.
Joel Montalbano, ISS program manager at NASA, told reporters last week that the United States was keeping a close eye on a small leak on the Russian side of the research platform, the latest of several recent issues on the Russian side.
A hatch is currently closed to isolate the leak from the rest of the ISS.