The fate of two NASA astronauts, who have been in limbo aboard the International Space Station for about 80 days due to problems with their Boeing Starliner spacecraft, may soon become clear.
The space agency said it will conduct a formal investigation on Saturday to determine whether the Boeing Starliner vehicle is safe enough to return home with its crew, or whether SpaceX's workhorse Crew Dragon will need to step in to save the day.
NASA said it will share its decision after the review is completed on Saturday. A news conference was scheduled for 1 p.m. ET, or "approximately one hour" after the review is completed, according to an email from NASA. However, the space agency routinely postpones news conferences if discussions take longer than expected.
The Starliner vehicle, which carried astronauts Suni Williams and Butch Wilmore to the space station in early June, suffered setbacks with helium leaks and thrusters abruptly failing during the first portion of its first crewed test flight. Engineers spent weeks trying to better understand the issues, and Boeing said on Aug. 2 that it "remains confident" the spacecraft could return Williams and Wilmore to Earth.
However, NASA announced at a press conference on August 7 that discussions within the space agency about the safety of the Starliner capsule had evolved, prompting the federal agency to more seriously consider flying the astronauts home in a SpaceX Crew Dragon vehicle, which has flown about a dozen human space missions since 2020.
SpaceX was already scheduled to fly a routine mission to the International Space Station, carrying four astronauts as part of standard crew rotations aboard the orbital laboratory. But the mission, dubbed Crew-9, could now be reconfigured to carry two astronauts instead of four.
That change would leave two empty seats for Williams and Wilmore to fill on the Crew 9 flight home. The astronauts would also officially join the Crew 9 team and become part of the official expedition. With that transition, Williams and Wilmore would remain in place for another six months - the length of a routine mission to the space station.
The move to Crew-9 could push the duo's return to February 2025.
Starliner would fly home empty in that scenario. And NASA would have to decide whether the data Starliner collected during its mission is enough to give the space agency the confidence to officially certify Starliner for human spaceflight - a step that would set the vehicle up for routine trips to orbit.
Faulty thrusters
Five of the Starliner's 28 "reaction control thrusters" failed during the first part of Boeing's test mission. All but one were eventually recovered.
Williams and Wilmore were expected to spend only eight days in space. However, their stay aboard the space lab has already been extended by about two months as engineers on the ground work to better understand the problems with the booster.
Officials said ground tests were able to simulate how the thrusters deteriorated in space during flight. The possible cause was heat building up inside the thrusters, which could cause insulating seals to swell and restrict the flow of fuel, Boeing said.
In addition, helium leak problems could result from seals compromised by exposure to propellant vapors, Mark Nappi, manager of Boeing's Commercial Crew Program, said July 25.
Still, NASA has struggled to reach consensus on how these problems could affect astronauts' return from space, and how great a risk the problems would pose.
The uncertainty about the level of risk is why the agency may turn to SpaceX and its workhorse Crew Dragon.
Starliner's rocky path
NASA has repeatedly said that SpaceX's ability to intervene highlights how the space agency deliberately designed its Commercial Crew Program - under which both Starliner and Crew Dragon were developed - so that each spacecraft could serve as a backup to the other.
"We're in kind of a new situation here, and we have multiple options," Ken Bowersox, deputy director of NASA's Space Operations Mission Directorate, said Aug. 7. "That's something we're going to have to deal with in the future - we could end up in a situation where we have to bring a (SpaceX) Dragon crew or a (Russian) Soyuz crew back on a Starliner.
"That's why we want multiple vehicles so we have that option," Bowersox added.
Yet in 2014, the federal agency simultaneously funded SpaceX's Crew Dragon and Boeing's Starliner. Crew Dragon has been operational for four years, while the Starliner program is hundreds of millions of dollars over budget and years behind schedule.
Boeing's development process was also plagued by missteps.
For example, the first Starliner test mission - which flew without a crew in 2019 - failed in orbit, ending its flight well short of expectations. The vehicle ultimately failed to dock with the space station as intended, and the outcome turned out to be a symptom of numerous software glitches, including a coding error that threw an internal clock off by 11 hours.
A second unmanned flight test in May 2022 revealed additional software issues, and mission teams addressed problems with some of the vehicle's thrusters. However, the root cause of the thruster issues that plagued this manned mission was missed two years ago.
Whether the Starliner vehicle ultimately achieves certification after its return to Earth is likely to be a contentious issue, especially if the spacecraft fails to bring Williams and Wilmore home and performs as intended during re-entry into Earth's atmosphere - considered the most dangerous part of the mission. The autonomous vehicle will have to use its thrusters to precisely orient itself as it falls back into Earth's thick atmosphere. The pressure and friction are expected to heat the outside of the vehicle to about 3,000 degrees Fahrenheit (1,650 degrees Celsius).
Starliner's parachutes must then deploy smoothly and slow the spacecraft before deploying airbags to soften the landing.
If the Starliner capsule eventually achieves certification, it could join SpaceX's Crew Dragon to make routine trips to the space station to rotate personnel. Currently, those trips occur about every six months.
And if the spacecraft fails to achieve certification, it would be another blow to Boeing's already badly damaged reputation. Missing the target could cost the company millions of dollars more - on top of the roughly $1.5 billion it has already lost on the Starliner program.
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