The NASA-SpaceX Crew-10 mission is set to launch from the Kennedy Space Center in Florida at 7:48 PM (2348 GMT) on Wednesday. The SpaceX Falcon 9 rocket carries a Crew Dragon capsule with a four-member team on a scientific expedition to the orbital lab.

All eyes however will be on astronauts Butch Wilmore and Suni Williams who have been stuck aboard the ISS since June after their Boeing Starliner spacecraft developed propulsion issues and was deemed unfit for their return.

The pair, initially slated for an eight-day mission, were reassigned to Crew-9 after its astronauts arrived in September aboard a SpaceX Dragon. The spacecraft carried only two crew members instead of the usual four to make room for Wilmore and Williams. Crew-9 will remain in orbit until Crew-10 arrives.

"We came up prepared to stay long, even though we plan to stay short," Wilmore said in a recent news conference. "That's what your nation's human space flight program is all about, planning for unknown, unexpected contingencies."

Crew-10 is expected to dock early Thursday, followed by a brief handover before Crew-9 departs on March 16 for an ocean splashdown off the Florida coast, weather permitting. Along with Wilmore and Williams, NASA astronaut Nick Hague and Russian cosmonaut Aleksandr Gorbunov will also be aboard the returning Dragon capsule.

Wilmore and Williams's prolonged stay has recently become a political flashpoint, as President Donald Trump and his close advisor Elon Musk have accused ex-president Joe Biden's administration of abandoning the pair.

SpaceX boss Musk has suggested, without providing specifics, that he had offered Biden a "rescue" mission outside of the routine crew rotations.

However, with Trump now in office for nearly two months, the astronauts are still set to return as originally planned.

The issue recently sparked a heated online exchange between Musk and Danish astronaut Andreas Mogensen, whom Musk called "fully retarded." Retired astronauts Scott and Mark Kelly and Chris Hadfield defended Mogensen.

One astronaut who backed Musk however was Wilmore, who offered contradictory statements in last week's press conference.

"I can only say that Mr. Musk, what he says is absolutely factual," he said, seemingly endorsing the SpaceX founder's version of events, before adding "politics is not playing into this at all."

"We have the utmost respect for Mr. Musk, and obviously respect and admiration for our president of the United States, Donald Trump. We appreciate them... and we're thankful that they are in the positions they're in," he continued.

The Crew-10 team consists of NASA astronauts Anne McClain and Nichole Ayers, Japan's Takuya Onishi, and Russia's Kirill Peskov.

During their mission, they will conduct a range of scientific experiments, including flammability tests for future spacecraft designs and research into the effects of space on the human body.

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