How NASA is striving to rescue stucked Astronauts

The US space agency has acknowledged that astronauts from NASA who were left behind on the International Space Station (ISS) following the demise of Boeing's Starliner might not be able to leave until 2025. It was intended to be an eight-day mission and the first human test flight for Starliner when commander Barry "Butch" Wilmore and pilot Sunita "Suni" Williams arrived at the International Space Station in June.

However, due to issues with the thrusters and propulsion system, the two were unable to return home, and NASA is unsure of whether Starliner, which is still docked at the space station, can be repaired.

NASA said that this week, it would like to return Mr. Wilmore and Ms. Williams home via the future SpaceX Crew-9 mission.

Instead of four astronauts, just two would go to the space station in a modified SpaceX Crew Dragon as part of the rescue plan. Following that, Mr. Wilmore and Ms. Williams would take the extra seats back, but since their return trip isn't expected until February 2025, they will have to spend an additional six months in space. NASA's head of space operations, Ken Bowersox, stated: "Butch and Sunny must eventually be brought home." "We have more workers and hands up there, so they can accomplish a lot more work, but they are also depleting more supplies and consumables, so we need to keep that balance." 

From the beginning, the Starliner project has been plagued with issues. Nasa requested offers for a new all-American crew vehicle since it was compelled to use the Russian Soyuz to reach the International Space Station (ISS) when the space shuttle was decommissioned in 2011.

NASA selected SpaceX and Boeing in 2014 to construct two crew modules that could transport people to the International Space Station. SpaceX, on the other hand, finished the brief in just six years and launched its first crew in November 2020, while Boeing fell years behind due to persistent technical problems. Several test launches were canceled or postponed at the last minute; the first flight, on June 5, involving Mr. Wilmore and Ms. Williams, was also briefly canceled as engineers resolved a "sticky valve."

A Teflon seal appears to be expanding and obstructing the fuel flow at the White Sands Test Facility in New Mexico, according to NASA's troubleshooting report.

However, engineers face another challenge if they are unable to resolve the thruster problems and leaks. Starliner must separate and return to Earth on its own so that the rescue ship can use its freed port when SpaceX Crew Dragon docks at the space station.

The capsule lacks the backup software required to undock without crew, and there are concerns that it could not be able to move away from the space station far enough to prevent a collision if thruster power is insufficient.

NASA expressed confidence in the ability to undock without colliding with the International Space Station.

NASA's International Space Station program manager, Dana Weigel, stated: "We're not concerned about the immediate proximity around the ISS because we have sufficient fault tolerance for undocking." 

NASA's commercial crew program manager, Steve Stich said “I want to reiterate we haven’t made a decision yet relative to return Butch and Sunny on Starliner or on [Crew Dragon],”

He also stated that "There has been a lot of work with Boeing and the SpaceX team, and it has been a very complicated timeline."