Boeing Starliner astronauts on extended stay at space station conduct a spacewalk

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Astronauts Suni Williams and Butch Wilmore, who have been on an unexpectedly monthslong assignment after serving on Boeing’s Starliner crewed test flight, are conducting a spacewalk Thursday. The duo is venturing outside the International Space Station to collect samples that may show whether microorganisms exist on the exterior of the orbiting laboratory.

The spacewalk began at 7:43 a.m. ET and will last for about 6 ½ hours. The entirety of the spacewalk will be streamed on NASA+ and NASA’s YouTube channel.

Williams is wearing a white suit marked with red stripes, while Wilmore is in an unmarked suit during the 274th spacewalk to help maintain and upgrade the station. It is Williams’ ninth career spacewalk and the fifth for Wilmore.

The veteran NASA astronauts’ tasks outside the space station will include removing some degraded radio communications hardware, which will be returned to Earth and refurbished on the ground, and preparing a spare joint for the Canadarm2 robotic arm in case it’s needed to replace the elbow of the 55-foot-long (17-meter-long) tool.

The Canadarm2, the Canadian robotic arm initially used in the space station’s assembly, now helps to move supplies, equipment and even astronauts around during spacewalks and also “catches” spacecraft and helps those vehicles dock to the station.

The astronaut duo will swab different places outside the space station for the ISS External Microorganisms experiment, which focuses on collecting samples near life support system vents to see whether the space station releases microorganisms.

Any spacecraft and spacesuits that arrive at the space station are thoroughly sterilized ahead of their missions, but humans carry their own sets of microorganisms, which constantly regenerate.

Understanding which microorganisms can survive the sterilization process and make it to the space station could inform changes needed to be made to the cleaning process before humans plan a return to the lunar surface through the Artemis III mission later this decade, and eventually, aim to land on Mars for the first time.

The agency follows strict requirements for planetary protections, which seek to limit any human contamination of extraterrestrial environments — and prevents returning any contaminants from those environments to Earth.

Scientists want to know how many, if any, microorganisms are released into space by the orbiting laboratory, how they can survive and reproduce in the cosmic environment, and how far the microorganisms could travel.

On Earth, organisms living in harsh environments, such as hydrothermal vents in the ocean floor, are called extremophiles, and the experiment could reveal which microorganisms are hardy enough to exist amid the harsh radiation of space.

Returning to Earth

Increasing attention has been paid to Wilmore and Williams’ current venture in space, which began in June when the astronauts launched to the space station aboard Boeing’s Starliner spacecraft during its first crewed journey.

The duo was initially expected to return to Earth about eight days later. But problems with Starliner, including helium leaks and propulsion issues, led NASA to decide it was too risky for the astronauts to use on their return flight, and the capsule was sent back to Earth empty.

NASA has opted to return Wilmore and Williams to Earth no earlier than late March aboard the SpaceX Crew-9 capsule, which is currently docked outside the space station. The duo will not return home before the next flight, Crew-10, arrives at the space station. When Williams and Wilmore do return home, they will have been in space for nearly 10 months.

In a previous interview with CNN last week, former NASA Administrator Bill Nelson, who led the agency under the Biden administration and stepped down from the post when President Donald Trump took office on January 20, spoke in-depth about the agency’s decision to extend the astronauts’ stay in space, emphasizing the determination was made with astronaut safety top of mind — and despite Boeing’s objections.

Among NASA leadership, the decision announced in August to fly Williams and Wilmore home on a SpaceX Crew Dragon rather than Starship was unanimous.

However, SpaceX CEO Elon Musk posted on his social media platform X Tuesday claiming the astronauts were “stranded” in space.

“The @POTUS has asked @SpaceX to bring home the 2 astronauts stranded on the @Space_Station as soon as possible. We will do so. Terrible that the Biden administration left them there so long,” Musk asserted in a post.

Trump shared similar sentiments on his social media platform Truth Social, posting, “I have just asked Elon Musk and @SpaceX to ‘go get’ the 2 brave astronauts who have been virtually abandoned in space by the Biden Administration. They have been waiting for many months on @Space Station. Elon will soon be on his way. Hopefully, all will be safe. Good luck Elon!!!”

When CNN reached out for comment from NASA, the agency shared that “NASA and SpaceX are expeditiously working to safely return the agency’s SpaceX Crew-9 astronauts Suni Williams and Butch Wilmore as soon as practical, while also preparing for the launch of Crew-10 to complete a handover between expeditions.”

“SpaceX will bring Butch and Suni back on a Dragon spacecraft as Crew 9 on a regular rotation after Crew 10 has arrived. The handover from one crew to the other is important to maintain the ISS and keep all astronauts safe,” Nelson said in a previous statement to CNN.

Despite the unexpectedly lengthy duration of their stay, which astronauts are accustomed to experiencing over the course of days, weeks or months, Wilmore and Williams have remained in good spirits and said they don’t feel “stranded.” Williams recently conducted her eighth career spacewalk on January 16 alongside fellow NASA astronaut Nick Hague.

“It’s just a great team and — no, it doesn’t feel like we’re castaways,” Williams said during a January 8 interview with then-NASA Administrator Nelson. “Eventually we want to go home because we left our families a little while ago, but we have a lot to do while we’re up here.”

CNN’s Jackie Wattles contributed to this report.

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