Tag: NASA

Boeing Starliner Returns Home to an Uncertain Future

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Until now, NASA has paid Boeing roughly $2.7 billion of the $4.6 billion total potential value of its commercial crew contract, according to Finch. The Starliner contract NASA awarded Boeing in 2014 originally had a maximum value of $4.2 billion, but contract modifications since 2014 have added $400 million to the deal. Most of the money NASA has paid Boeing to date has been for Starliner development costs, while the remaining funds under the contract cover future service payments for operational flights.

So, if Boeing walked away from Starliner, the company would be giving up nearly $1.9 billion on potential revenue from NASA, still more than the $1.6 billion in losses it has taken on the program so far.

Ready for Departure

Since deciding last month to fly Starliner home without its crew, NASA managers have reviewed plans for the spacecraft to depart the space station in autopilot mode. The preparations included updating Starliner’s software parameters to enable the autonomous undocking. Then, last Thursday, NASA officials convened a Flight Readiness Review and cleared Starliner to return to Earth.

“Everybody polled ‘go’ in that review, pending the operational status of the vehicle and the landing weather,” said Steve Stich, NASA’s commercial crew program manager. “So we’re proceeding toward undock and landing on Friday.”

As Starliner approached the space station on June 6, five of the ship’s 28 Reaction Control System (RCS) thrusters dropped offline, requiring Wilmore to take manual control while ground controllers tried to recover some of the control jets.

Engineers tested thrusters and analyzed data for over two months to track down the cause of the thrusters’ failure. Ground teams were able to bring four of the five failed thrusters back online, but NASA officials could not assure themselves the same thrusters, or perhaps more, won’t overheat again and fail as Starliner departs the station and heads for reentry.

Investigators found that repeated pulses of the RCS jets led to rising temperatures in the thrusters. This likely caused a seal in each of the problematic thrusters to bulge and deform, restricting the flow of propellant, according to NASA officials.

Stich said Wednesday that possible solutions to the problem on future Starliner flights range from changing the way the ship fires its thrusters to prevent overheating, to changing the seal design, to modifying the doghouse-shaped propulsion pods where the thrusters reside on the spacecraft’s service module. The design of these “doghouses” cause them to retain heat like a thermos, exacerbating the thermal problem.

Boeing and NASA also must resolve helium leaks that plagued the Starliner test flight. Engineers believe a separate set of degraded seals is causing helium leaks, which the spacecraft uses to pressurize the propulsion system and drive propellants into its thrusters. Ground controllers have closed valves to isolate the helium system and close off the leaks while Starliner has been docked at the space station. Those isolation valves will open before Starliner departs the space station, but NASA officials say the spacecraft has more than enough helium for the six-hour flight from undocking until landing Friday night.

Wilmore and Williams originally planned to stay at the space station for around eight days, but will now remain as residents on the complex until February, when they will come home in a SpaceX Dragon spacecraft.

Dana Weigel, NASA’s ISS program manager, said Wednesday that the Starliner astronauts, both veterans of previous six-month stays on the space station, are fully trained to perform spacewalks, operate the lab’s robotic arm, and conduct maintenance and scientific experiments. They will be fully integrated into the space station’s long-duration crew, which usually includes seven residents. With the Starliner crew’s extended stay, the station crew size has grown to nine people.

The crew shakeup forced NASA to remove two astronauts from the next SpaceX Dragon crew flight launching to the ISS later this month, leaving two seats empty to accommodate Wilmore and Williams when the Dragon spacecraft returns to Earth early next year. This upcoming SpaceX crew rotation will bring the station crew size back to its usual complement of seven US astronauts and Russian cosmonauts.

This story originally appeared on Ars Technica.

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September 6, 2024
The Starliner stranding shows why NASA was wise to have a backup plan

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After any problem with a rocket launch or mission, experts echo the same refrain: space is hard. As progress in the space industry accelerates, that mantra is becoming more relevant, not less, but that is because we are facing the difficulties of space flight more frequently – and, largely, overcoming them.

The situation unfolding on the International Space Station (ISS) over the past few months is a perfect example. Boeing’s Starliner spacecraft launched for its first crewed flight on 5 June, but hardware issues meant that once it arrived at the ISS, it was unclear if it would be safe for the two NASA astronauts it carried to safely ride it back to Earth as planned.

So, after testing on the ground and much deliberation, NASA pivoted and announced that the astronauts would be extending their stay in space and coming home in February 2025 aboard a SpaceX Crew Dragon craft instead (see “Stranded ISS astronauts reveal the US space programme is not in crisis”). Thanks to the wise decision NASA made a decade ago to choose two companies to build capsules to shuttle astronauts into space instead of just one, a potentially devastating issue became a mere inconvenience. We have known the whole time that space is hard, and preparation paid off.

The first ever civilian spacewalk may well be the most dangerous spacewalk of all time

Hopefully, intense preparation will also pay off for the crew of SpaceX’s upcoming Polaris Dawn mission. If all goes well, it will include the first ever civilian spacewalk, which may well be the most dangerous spacewalk of all time (see page 8).

If the walk goes smoothly, it will be another big win for commercial space flight and for SpaceX in particular – not least because it will be the first test of the firm’s new spacesuits. Ageing suits have been a looming problem for NASA and other space agencies for decades – those in use by NASA are the same ones astronauts wore in the 1980s, and they are long past their prime. A reliable new spacesuit that even civilians can wear comfortably, with improved mobility and temperature control, would be a huge win. It would make space just a little bit less hard.

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September 4, 2024
Moon GPS Is Coming | WIRED

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“I refer to LunaNet as the big umbrella,” Gramling says. “It is an architecture that defines the standards that are going to be used for interoperable communications and position, navigation, and timing services. There’s a large effort underway to define those standards and document those in a LunaNet interoperability specification.”

“It’s a very different paradigm than Earth, where the US has GPS, Europe has Galileo, or Russia has GLONASS,” she adds. “Because we’re at early stages, the idea is that we have to work together as three partners that are involved so far in LunaNet, and assert one system among the three of us.”

In other words, while NASA, ESA, and JAXA work away on their separate projects for now, they plan to ultimately merge those ideas into a single operating system. The detailed plans for ESA’s Moonlight Initiative are helpful for picturing how a lunar GNSS constellation might ultimately shake out.

As currently envisioned by ESA, Moonlight would consist of at least five satellites, including a large communication satellite and four smaller dedicated navigation satellites, placed in special orbits to optimize coverage at the lunar south pole. This initial setup would provide 15 reliable and predictable hours of PNT services in the coverage area every 24 hours, but Moonlight is also designed to be scalable, meaning more satellites could be added to enlarge the service area or to support more complicated missions.

“Moonlight will provide an extraordinary paradigm shift in the field of exploration,” says Javier Ventura-Traveset, who serves as Moonlight navigation manager at ESA. “Instead of each lunar mission requiring their own complex communication and navigation systems with a heavy dependence on Earth-based support, thanks to Moonlight, future missions will have access to broadband communication services and GNSS-like navigation systems directly from lunar orbit, all under a service contract with a commercial provider.”

It’s unclear the extent to which China, or any other nations, might collaborate on existing lunar navigation constellations systems, or if the moon will end up with multiple versions of GNSS, similar to Earth. Earlier this summer, a team of scientists at the China Academy of Space Technology outlined a phased plan for a GPS-style constellation in the journal Chinese Space Science and Technology.

“China has expressed interest in developing lunar navigation infrastructure at several international forums and has already launched this year the Queqiao-2 satellite, a lunar communication relay satellite,” notes Ventura-Traveset. “Similar to ESA, NASA, and JAXA, it is likely that China will also develop its own lunar navigation constellation. At some of these international forums, China has also indicated an interest in pursuing international interoperability.”

The emergence of these multiple competing concepts has led some to wonder if have entered a new “space race” to establish the first lunar version of GPS. But Gramling doesn’t see it that way. “I just know that we are putting our heads down and working with our partners because we have missions that we have to support in the relatively near term,” she says. “We’re just trying to focus on making sure that, among the partners that we’re working on LunaNet, that we are assured of what services we’re trying to provide and that we work together.”

Patla pointed out that last month, the International Astronomical Union, an organization that mediates a host of astronomical issues, voted on a resolution that emphasized cooperation in establishing a lunar timescale and other elements of lunar PNT systems.

“At least at the beginning stages, collaboration would be cheaper, and it would also benefit everyone,” Patla says. “But we don’t know how this will pan out.”

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September 4, 2024
Strange Noises Are Coming from Inside Boeing’s Starliner Spacecraft

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On Saturday NASA astronaut Butch Wilmore noticed some strange noises emanating from a speaker inside the Starliner spacecraft.

“I’ve got a question about Starliner,” Wilmore radioed down to Mission Control, at Johnson Space Center in Houston. “There’s a strange noise coming through the speaker … I don’t know what’s making it.”

Wilmore said he was not sure if there was some oddity in the connection between the station and the spacecraft causing the noise, or something else. He asked the flight controllers in Houston to see if they could listen to the audio inside the spacecraft. A few minutes later, Mission Control radioed back that they were linked via “hardline” to listen to audio inside Starliner, which has now been docked to the International Space Station for nearly three months.

Wilmore, apparently floating in Starliner, then put his microphone up to the speaker inside Starliner. Shortly thereafter, there was an audible pinging that was quite distinctive. “Alright Butch, that one came through,” Mission control radioed up to Wilmore. “It was kind of like a pulsing noise, almost like a sonar ping.”

Listen to a recording of the noises heard by Butch Wilmore.

“I’ll do it one more time, and I’ll let y’all scratch your heads and see if you can figure out what’s going on,” Wilmore replied. The odd, sonar-like audio then repeated itself. “Alright, over to you. Call us if you figure it out.”

A Space Oddity

A recording of this audio, and Wilmore’s conversation with Mission Control, was captured and shared by a Michigan-based meteorologist named Rob Dale.

It was not immediately clear what was causing the odd, and somewhat eerie noise. As Starliner flies to the space station, it maintains communications with the space station via a radio frequency system. Once docked, however, there is a hardline umbilical that carries audio.

Astronauts notice such oddities in space from time to time. For example, during China’s first human spaceflight int 2003, astronaut Yang Liwei said he heard what sounded like an iron bucket being knocked by a wooden hammer while in orbit. Later, scientists realized the noise was due to small deformations in the spacecraft due to a difference in pressure between its inner and outer walls.

This weekend’s sonar-like noises most likely have a benign cause, and Wilmore certainly did not sound frazzled. But the odd noises are worth noting given the challenges that Boeing and NASA have had with the debut crewed flight of Starliner, including substantial helium leaks in flight, and failing thrusters. NASA announced a week ago that, due to uncertainty about the flyability of Starliner, it would come home without its original crew of Wilmore and Suni Williams.

Starliner is now due to fly back autonomously to Earth on Friday, September 6. Wilmore and Williams will return to Earth next February, flying aboard a Crew Dragon spacecraft scheduled to launch with just two astronauts later this month.

This story originally appeared on Ars Technica.

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September 2, 2024
Starliner failure: Stranded ISS astronauts reveal the US space programme is not in crisis

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Boeing’s Starliner capsule won’t shuttle astronauts home from space this year

NASA

It’s official: Butch Wilmore and Sunita Williams are staying on the International Space Station (ISS) until at least February. This is a major setback for Boeing’s Starliner, the capsule that brought them there, but it doesn’t spell doom for the US space programme. Instead, it highlights the success of the move from governments providing the only rockets to space to the proliferation of commercial spaceflight options.

This is exactly the contingency NASA’s Commercial Crew Program, which uses spacecraft built by private companies to ferry astronauts to and from the ISS, was planned to handle. “Commercial Crew purposefully chose two providers for redundancy in case of exactly this kind of situation,” says Laura Forczyk, an independent consultant in the space industry. The two NASA astronauts were initially supposed to return to Earth about a week after they arrived at the ISS aboard Boeing’s Starliner capsule on 5 June. But due to problems with the spacecraft, they will now stay for an extended mission before coming home on a SpaceX Crew Dragon craft instead of Starliner.

“If they had only selected one provider, it would have been Boeing, because SpaceX was the risky prospect at the time,” says Forczyk. “So in a way, this is a triumph of the Commercial Crew Program.”

This mission was Starliner’s first crewed test flight, and it was rocky from the start. Leaky valves and thruster failures during the journey into space forced NASA and Boeing to reconsider whether the craft would be safe to shuttle the astronauts home. They ran tests of the thrusters on the ground, and the results were inconclusive – there was still some risk of the thrusters failing on the way home.

The safest backup plan is for the astronauts to stay on the ISS until SpaceX’s tried-and-true Crew Dragon capsule has room to bring them home in early 2025. In the meantime, Starliner will autonomously undock from the ISS in September and return to Earth without crew, and Boeing engineers will continue troubleshooting.

“This was a test mission, but sometimes in tests, the answer is, you’ve got something you need to fix,” said retired NASA astronaut Michael Fossum in a statement. “Tests don’t always prove that everything worked perfectly.”

In a 24 August press conference, NASA administrator Bill Nelson was adamant that Starliner will get another shot at flying a crew to the ISS, but others aren’t so sure. Boeing’s contract states that the craft cannot be certified for real missions until it has had a successful test flight – which this was not. If NASA requires Starliner to do another test flight, it could push the first operational flight until 2026 at the earliest, says Forczyk. With the ISS slated to close up shop around 2030, getting Starliner ready for active duty may just not be worth it.

Without the redundancy of the Commercial Crew Program, Starliner’s failure could have left the US wholly without a launch provider. As it is, SpaceX will continue shuttling astronauts to and from the ISS. Wilmore and Williams will have to stay on the ISS a bit longer, but they are veteran astronauts and have the experience and equipment to jump right into daily life in space until they can be brought safely back to Earth.

It is even possible the hard work and inconvenience of an extended stay might not outweigh the excitement of life in orbit for Wilmore and Williams. “I know them really well, and in a way, I think they were a little disappointed to fly in space with such a short amount of time,” said Fossum. “They both also have done long duration missions on the space station before… and they both loved it.”

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August 28, 2024
The Boeing Starliner Astronauts Will Come Home on SpaceX’s Dragon Next Year

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NASA has announced that astronauts Barry Wilmore and Sunita Williams will return to Earth next February aboard SpaceX’s Dragon spacecraft.

The announcement at a press conference today caps off months of speculation about the best plan to safely bring the astronauts home after malfunctions with their ride, Boeing’s Starliner capsule, postponed their departure from the International Space Station in June. Now, NASA has decided that Starliner will return home without Wilmore and Williams, who will stay on with the existing station crew and will return on SpaceX’s Crew-9 mission next year.

“Boeing has worked very hard with NASA to get the necessary data to make this decision,” NASA administrator Bill Nelson said at the briefing. “We want to further understand the root causes and understand the design improvements so that the Boeing Starliner will serve as an important part of our assured crew access to the ISS.”

Wilmore and Williams launched from Cape Canaveral, Florida, on June 5, becoming the first astronauts to perform a crewed test flight of Starliner, a capsule developed by Boeing to ferry people to and from the ISS.

During the approach to the station, five of Starliner’s 28 thrusters failed to function. The crew was able to restore four of them and safely docked with the station, where they discovered Starliner’s propulsion system was also leaking helium from multiple places.

Wilmore and Williams were originally scheduled to stay onboard the ISS for about a week before returning to Earth in Starliner. But their return has been delayed for more than two months as mission planners struggled to isolate the cause of the thruster problems and assess the risks of using Starliner for the flight home. NASA’s plan will leave them on ISS for a total of eight months, longer than the typical six-month stay but not unprecedented.

Instead of sending a four-person crew to the ISS onboard SpaceX’s Dragon in September as planned, two of the seats on the capsule will be left open for Wilmore and Williams. New Dragon spacesuits for the astronauts, along with other necessary supplies, will be brought to the station in the coming months.

NASA has emphasized that Wilmore and Williams have not been “stranded,” nor are they in any danger. Likewise, the astronauts have publicly approached the extended stay as a lucky break that lets them rack up more time in space.

“We are having a great time here on ISS,” Williams told reporters in a July call from the ISS. “You know, Butch and I have been up here before, and it feels like coming back home. It feels good to float around. It feels good to be in space and work up here with the International Space Station team.”

Cargo ships regularly dock with the ISS, providing enough supplies for all crew members onboard, and NASA considers Starliner to be safe enough for the astronauts to use in the case of an emergency evacuation of the ISS. NASA and Boeing have disagreed in recent weeks on the safety of Starliner. Whereas NASA has decided that the unresolved questions about Starliner require a crew and spacecraft shuffle, Boeing has maintained that Starliner is up to the safety standards required to complete the crewed mission.

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August 24, 2024
Why NASA is sending a probe to Europa – and what it’s looking for

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Seen against the backdrop of Jupiter’s dramatic, swirling atmosphere, Europa might at first appear a bit drab. With its greyish-white surface, you might even say it resembles a well-worn cue ball in a run-down pool hall. On closer inspection, however, the Jovian system’s fourth-largest moon is shimmering with intrigue from deep within.

From what we can tell, its icy outer layer conceals a vast global ocean containing twice the volume of water on Earth. This, in addition to hints of geophysical activity – such as the rusty lines that streak its surface – and complex chemistry, is why Europa has long captivated astronomers searching for habitable worlds beyond our pale blue dot. So could Europa have the conditions for life? We’re about to find out.

In October, NASA will launch Europa Clipper, a $5 billion probe that will get a closer look at the moon’s geology and chemistry – and, with any luck, identify the telltale signatures of habitability. The mission has been decades in the making, building on previous forays that have thrown up tantalising clues as to what lurks inside the moon’s frozen shell – and no shortage of questions.

Clipper promises answers. It will study the moon’s surface and the ocean hidden beneath in unprecedented detail. It could even sample the water in plumes of vapour if, as we suspect, they are erupting from Europa’s surface. And although it isn’t designed to find direct evidence of life – a bacterial cell, say – recent developments suggest there is a fleeting chance it could do exactly that. “With Europa Clipper, we’re really entering…

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August 21, 2024
NASA Nears Decision Time on Boeing Starliner’s Fate

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With no consensus on the safety of the Starliner crew capsule, NASA officials said Wednesday they need another week or two before deciding whether to bring two astronauts back to Earth on Boeing’s spacecraft or extend their stay on the International Space Station until next year.

Boeing’s Starliner spacecraft, stricken by suspect thrusters and helium leaks, is taking up a valuable parking spot at the space station. It needs to depart the orbiting research complex, with or without its two-person crew, before the launch of SpaceX’s next Dragon crew mission to the station, scheduled for September 24.

“We can juggle things and make things work if we need to extend, but it’s getting a lot harder,” said Ken Bowersox, associate administrator of NASA’s spaceflight operations directorate. “With the consumables we’re using, with the need for the use of the ports for cargo missions, those types of things, we’re reaching a point where that last week in August, we really should be making a call, if not sooner.”

Last week, NASA officials said they expected to make a decision in mid-August—presumably this week—but Bowersox said Wednesday NASA probably won’t make the final call on what to do with the Starliner spacecraft until the end of next week, or the beginning of the week of August 26.

“We’ve got time available before we bring Starliner home and we want to use that time wisely,” Bowersox said.

NASA astronauts Butch Wilmore and Suni Williams launched inside Boeing’s Starliner spacecraft on June 5. Their mission is the first crew test flight on Boeing’s capsule before NASA clears Starliner for regular crew rotation flights to the space station. But after software setbacks, parachute concerns, and previous problems with its propulsion system, Boeing’s Starliner program is running more than four years behind SpaceX’s Dragon crew spacecraft, which flew astronauts to the station for the first time in 2020.

And now, there’s a significant chance the Starliner crew won’t come home in the spacecraft they launched in. Bowersox, a former astronaut, said NASA brought in propulsion experts from other programs to take a fresh look at the thruster issue.

Engineers are still investigating the root cause of why five of Starliner’s 28 reaction control system thrusters, supplied by Aerojet Rocketdyne, failed during approach to the space station the day after launch. The thrusters overheated as they pulsed over and over again to fine-tune the ship’s rendezvous with the station. Tests of a similar control jet on the ground suggested a Teflon seal in an internal valve could swell at higher temperatures, restricting the flow of propellant to the thruster.

Four of the five thrusters that failed before Starliner docked at the station have recovered and generated near-normal thrust levels during test-firings last month. But many engineers at NASA aren’t convinced the thrusters will work normally on Starliner’s journey from the space station back to Earth. These control jets are needed to keep the spacecraft pointed in the right direction when four larger rocket engines fire for the deorbit burn to steer the capsule on a trajectory back into the atmosphere for landing.

Rapid pulses of the thrusters, coupled with a long firing of the four larger engines, could raise temperatures inside four doghouse-shaped propulsion pods around the perimeter of Starliner’s service module. Once the deorbit burn is complete, Starliner will jettison the service module to burn up in the atmosphere, and its crew module will use a different set of thrusters to guide its reentry. Then, it will deploy parachutes to slow for landing, likely at White Sands, New Mexico.

Elevated risk

Bowersox said the outside engineers brought in from other NASA centers have, so far, largely agreed with the assessments made by the team working full time on Starliner.

“There are a lot of folks out there that have worked with similar thrusters, and have seen similar issues,” he said. “So we’ve gotten feedback on what we’re seeing, and a lot of it is confirming what we thought was causing the signatures that we were observing on orbit. It’s really tough when you don’t have the actual hardware to look at, when it’s up in space.”

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August 16, 2024
NASA Still Hasn’t Decided How to Get the Boeing Starliner Astronauts Home

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During a news conference on Wednesday, NASA officials for the first time publicly discussed divisions within the agency about whether the Starliner spacecraft is really reliable enough to return two veteran astronauts—Butch Wilmore and Suni Williams—back to Earth from the International Space Station.

The space agency also confirmed key elements exclusively reported by Ars over the past week, chiefly that NASA has quietly been working for weeks with SpaceX on a potential rescue mission for Wilmore and Williams, that the Crew-9 mission launch has been delayed to September 24 to account for this possibility, and that Starliner is unable to undock autonomously with the current software configuration on the vehicle.

The chief of space human spaceflight operations for NASA, former astronaut Ken Bowersox, said no final decisions have been made on how Wilmore and Williams return to Earth. He said there were reasonable disagreements among engineers at NASA, which is the customer for the spaceflight, and Boeing, which developed and operates Starliner, about the viability of the 28 reaction control system thrusters that are used for delicate maneuvering and pointing of the vehicle.

“I think it’s been very healthy,” Bowersox said of these internal discussions during a call with reporters on Wednesday. “I have to admit that sometimes when we get disagreement, it’s not fun. It can be painful having those discussions, but it’s what makes us a good organization.”

NASA has been studying various contingencies, but officials appear to have settled on two different options for bringing the two astronauts back to Earth. They could still fly back on Starliner if NASA engineers become more comfortable with the uncertainty about the thruster performance, and if so, they would do so during the second half of this month or the first part of September. Alternatively, NASA could launch the Crew-9 mission with a complement of two rather than four astronauts, and Wilmore and Williams would join that “increment” on the space station and fly back to Earth in February 2025.

Asked if he thought one of the two scenarios was more likely than the other, Bowersox said he could not say. However, a final decision will be made fairly soon. Bowersox said NASA needs to choose the astronauts’ return path by mid-August.

Thruster Issues

NASA’s concern about Starliner’s thrusters boils down to the failure of five of them during the vehicle’s ascent to the space station. Starliner’s flight computer shut off five thrusters, provided by Aerojet Rocketdyne, in flight. Four of the five thrusters were recovered after overheating.

Since then Boeing and NASA have conducted ground- and space-based tests of the small thrusters to try to replicate the failure and better understand, fundamentally, what is occurring. By getting to the root cause, the engineers will feel confident in their ability to address the problem for Starliner’s flight back to Earth.

In ground tests, the engineers were able to demonstrate similar failures. Subsequent inspections showed bulging in a Teflon seal in an oxidizer valve known as a “poppet,” which could restrict the flow of nitrogen tetroxide propellant. The thrusters consume the nitrogen tetroxide and mix it with hydrazine fuel for combustion. Despite the tests, however, engineers still don’t understand precisely why the bulging is occurring and whether it will manifest on Starliner’s flight back to Earth.

“People really want to understand the physics of what’s going on relative to the physics of the Teflon, what’s causing it to heat up, and what’s causing it to contract,” said Steve Stich, who manages the Commercial Crew program for NASA. “That’s really what the team is off trying to understand. I think the NASA community in general would like to understand a little bit more of the root cause.”

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August 8, 2024
Starliner: Two NASA astronauts may be stuck on the space station until February

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Astronauts Butch Wilmore and Sunita Williams on the International Space Station

NASA

NASA astronauts Butch Wilmore and Sunita Williams may be stuck on the International Space Station (ISS) until February 2025 after issues cropped up with the spacecraft they rode to the station. This was the first crewed test flight of that capsule, Boeing’s Starliner, and it is not yet clear whether it will be safe for Wilmore and Williams to use it to get home.

Starliner launched on 5 June, with the intention of spending about a week docked to the ISS before shuttling the astronauts back to Earth. The launch had been delayed by a myriad of small problems with the spacecraft, and even on the day of lift-off the craft experienced minor helium leaks that engineers decided were not enough of a problem for another delay.

But by the time it reached the ISS, more helium leaks had sprung and five of Starliner’s 28 thrusters had failed. Wilmore and Williams boarded the ISS safely – but it is now a month beyond their planned return to Earth, and the next move is uncertain.

“When we started this mission, it was a test mission,” said Ken Bowersox at NASA during a 7 August press conference. “We knew that it potentially had a higher risk than a flight on a vehicle that has more experience.” Now, he says there are disagreements within NASA as to whether the risk of more leaks and thruster failure during a return flight is too high to put people back on board Starliner.

A major part of assessing that risk has been attempting to recreate the issues that Starliner has seen in space with tests on the ground, said NASA’s Steve Stich during the press conference. He said there has been some progress, but not yet enough to significantly lower the uncertainty in how Starliner will perform on its way back to Earth. “We can’t totally prove with certainty [that] what we’re seeing on orbit is exactly what we’re seeing on the ground,” said Stich.

Of course, this does not mean that Wilmore and Williams will be stuck aboard the ISS forever – there are contingency plans. If NASA does decide that the risks with Starliner are too high, Starliner’s software will have to be reconfigured for an autonomous, uncrewed return to Earth. Then, the SpaceX Crew Dragon capsule currently docked to the ISS will be reconfigured to carry two extra astronauts.

But that isn’t the main option. There is another plan to bring the astronauts home using the next Crew Dragon that is launched. The date for that launch was just delayed to September – it was originally intended to carry four astronauts to the ISS, but it may carry only two, leaving room for Wilmore and Williams when the mission is over in February 2025.

Wilmore and Williams are trained to perform all of the planned activities for that mission, including spacewalks, but this plan would extend their stay in space from the scheduled eight days to nearly eight months. NASA has already directed SpaceX and Boeing to start working on the updates needed to make either plan happen, but a choice has not been made yet.

“Those are backup contingency plans,” said ISS manager Dana Weigel at the press conference. “We have not made any decisions at all in terms of anchoring to a specific plan.” Stich said that a decision is likely to be made in mid-August. The greater impacts of this struggle on NASA’s Commercial Crew Program remain to be seen.

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August 7, 2024