NASA astronauts Sunita "Suni" Williams and Barry "Butch" Wilmore have been on the International Space Station since June, even though they initially expected to stay for just eight days. They'll be back on Earth in late March.But because their stay was extended, Williams set a new record on Thursday. She went on a 5 hour, 26 minute spacewalk with Wilmore, and with that walk, surpassed the record set by a woman for time spent on spacewalks. According to Space.com, Williams now has 62 hours and 6 minutes of spacewalking, surpassing former astronaut Peggy Whitson, who had 60 hours and 21 minutes.On this most recent spacewalk, the two worked to finally remove a faulty radio-communications unit, one that astronauts on two previous spacewalks were unable to remove.Williams previously teamed up with astronaut Nick Hague for a spacewalk onJan. 16. On that spacewalk, Williams and Hague replaced a rate gyro assembly that helps maintain the orientation of the orbital outpost, NASA said. The astronauts also installed patches to cover damaged areas of light filters on the Neutron star Interior Composition Explorer X-ray telescope, replaced a reflector device on one of the international docking adapters, and checked access areas and connector tools that astronauts will use for future Alpha Magnetic Spectrometer maintenance. NASA astronaut Suni Williams is seen outside the International Space Station during the Jan. 16, 2025, spacewalk. NASATrump and Musk Upgrade your inbox Get cnet insider From talking fridges to iPhones, our experts are here to help make the world a little less complicated. The astronauts are scheduled to come home in March. But that might not be fast enough for President Donald Trump."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," Trump wrote on Truth Social,according to NPR. "Good luck Elon!!!"The astronauts are far from abandoned. The delay was caused because NASA and Boeing engineers discovered issues with the spacecraft that brought the astronauts into space, and chose to return that vehicle to Earth without a crew.And it's unclear what Musk could do, since the two are already scheduled to fly home on a capsule made by his company, SpaceX, and that capsule is already docked at the ISS. So technically, the astronauts could go home at any time, but that would leave the space station short-staffed and jeopardize projects, NPR says.The two astronauts say that while they miss their families, they've still got work to keep them busy."Eventually we wanna go home," said Williams in a recent news conference. "We left our families a little while ago, but we have a lot to do up here and we have to get that stuff done before we go."February return is now MarchRecently, NASA pushed back Williams and Wilmore's return to Earth from February to late March."NASA and SpaceX assessed various options for managing the next crewed handover, including using another Dragon spacecraft and manifest adjustments," according to a NASA press release issued on Dec. 17. "After careful consideration, the team determined that launching Crew-10 in late March, following completion of the new Dragon spacecraft, was the best option for meeting NASA's requirements and achieving space station objectives for 2025.The delay is so NASA and SpaceX teams can complete work on the mission's new Dragon spacecraft. That new craft will launch four crew members to the ISS -- commander Anne McClain, commander, pilot Nichole Ayers, Japanese astronaut Takuya Onishi, and Roscosmos cosmonaut Kirill Peskov. Once the new crew is settled, Williams, Wilmore, NASA astronaut Nick Hague and Roscosmos cosmonaut Aleksandr Gorbunov will return to Earth.But Williams and Wilmore aren't complaining about their extended stay."I like everything about being up here," Williams saidin early December. "Living in space is super fun."The astronauts are keeping busy, with Williams and Wilmore assisting the other ISS residents in space botany studies and other research,according to NASA's ISS blog. They have aided in more than 60 scientific studies in their nearly six months on board,the Washington Post reports.Here's what you need to know about what the two astronauts are up to.Who are the astronauts?Wilmore, 61, and Williams, 58, are veteran astronauts and are both naval officers and former test pilots. Williams has been a NASA astronaut since 1998, and Wilmore since 2000. Both have plenty of experience in space.Williams is the former record holder for most spacewalks by a woman (seven) and most spacewalk time for a woman (50 hours, 40 minutes), and in 2007, she ran the first marathon by any person in space.In 2009, Wilmore piloted the Space Shuttle Atlantis on its mission to the ISS, and in 2014, he was part of the ISS crew that used a 3D printer to manufacture a tool -- a ratchet wrench -- in space, the first time humans manufactured something off-world.What was their original mission in space?Wilmore, as commander, and Williams, as pilot, traveled to the ISS on a 15-foot-wide, Boeing-made capsule called Starliner. They launched on June 5 and docked with the ISS on June 6. NASA hopes Starliner will give the organization a new way to get crews to and from the ISS, and the fact that it's Boeing-made is another sign that NASA is starting to lean on the private sector for its human spaceflight options, The New York Timesreported.Wilmore and Williams' ISS mission was supposed to last a mere eight days, during which they'd test out aspects of Starliner and see how it operates with a human crew in space. But due to complications with Starliner, the two astronauts are still up there.What are the astronauts saying?The astronauts have been positive about their experience. At alive news conferencein September, Williams said that despite knowing their mission was scheduled to take only eight days, they'd both been "training for a number of years" for it. They're fully qualified to remain in space for an extended period of time, and to help pilot the SpaceX Dragon spacecraft that'll bring them home next year."It's very peaceful up here," Williams said on Sept. 13, though she added that they miss their families back on Earth.The astronauts are working on research, maintenance and data analysis during their extended stay."We are having a great time here on ISS," Williams saidin a news conferenceheld from orbit in July. "I'm not complaining. Butch isn't complaining that we're up here for a couple of extra weeks." Wilmore and Williams responding to media questions back in March. Houston Chronicle/Hearst Newspapers/Getty ImagesHow did they get stuck in space in the first place?The Starliner was delayed in May due to a problem with a valve in the rocket. Then engineers had to fix a helium leak. That's all bad news for Boeing. It's competing with SpaceX, which has been transporting astronauts to the ISS since 2020, making over 20 successful trips to the space station. Starliner finally launched, atop an Atlas V rocket, on June 5, but some problems came along with it. NASA announced that three helium leaks were identified, one of which was known before flight, and two new ones. In addition to the leaks, the crew had to troubleshoot failed control thrusters, though the craft was able to successfully dock with the ISS. SpaceX has had failures too. A Falcon 9 rocket exploded on the launchpad in 2016. In July of this year, a Falcon 9 rocket experienced a liquid oxygen leak and deployed its satellites in the wrong orbit, The New York Times reported. And a Falcon 9 rocket in late August lost a first-stage booster when it toppled over into the Atlantic Ocean and caught fire.But that said, SpaceX has more than 300 successful Falcon 9 flights to its credit.Stuck in space: A timelineMay: Starliner launch delayed due to a problem with a valve in the rocket, and then a helium leak.June 5: Starliner launches with Williams and Wilmore on board.June 6: Starliner docks with ISS despite dealing with three helium leaks and failed control thrusters.Sept. 6: Starliner departs ISS and lands in New Mexico, leaving Williams and Wilmore behind.Sept. 28: SpaceX Crew-9 mission launches with Hague and Gorbunov on a Dragon spacecraft.Sept. 29: SpaceX Dragon docks with ISS.Dec. 17: NASA announces the launch of four crew members to the ISS will be delayed from February to late March.March 2025 onward: SpaceX Dragon spacecraft will return to Earth with Williams, Wilmore, Hague and Gorbunov.