Tag: NASA

NASA Is ‘Evaluating All Options’ to Get the Boeing Starliner Crew Home
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It has now been eight weeks since Boeing’s Starliner spacecraft launched into orbit on an Atlas V rocket, bound for the International Space Station. At the time NASA officials said the two crew members, Butch Wilmore and Suni Williams, could return to Earth as soon as June 14, just eight days later.

Yes, there had been some problems on Starliner’s ride to the space station that involved helium leaks and failing thrusters. But officials said they were relatively minor and sought to downplay them. “Those are pretty small, really, issues to deal with,” Mark Nappi, vice president and manager of Boeing’s Commercial Crew Program, said during a post-docking news conference. “We’ll figure them out for the next mission. I don’t see these as significant at all.”

But days turned to weeks, and weeks turned to months as NASA and Boeing continued to study the two technical problems. Of these issues, the more pressing concern was the failure of multiple reaction control system thrusters that are essential to steering Starliner during its departure from the space station and setting up a critical engine burn to enter Earth’s atmosphere.

In the last few weeks, ground teams from NASA and Boeing completed testing of a thruster on a test stand at White Sands, New Mexico. Then, last weekend, Boeing and NASA fired the spacecraft’s thrusters in orbit to check their performance while docked at the space station. NASA has said preliminary results from these tests were helpful.

Dragon Becomes a Real Option

One week ago, the last time NASA officials spoke to the media, the agency’s program manager for commercial crew, Steve Stich, would not be drawn into discussing what would happen should NASA conclude that Starliner’s thrusters were not reliable enough for the return journey to Earth.

“Our prime option is to complete the mission,” Stich said one week ago. “There are a lot of good reasons to complete this mission and bring Butch and Suni home on Starliner. Starliner was designed, as a spacecraft, to have the crew in the cockpit.”

For a long time, it seemed almost certain that the astronauts would return to Earth inside Starliner.

However, there has been a lot of recent activity at NASA, Boeing, and SpaceX that suggests that Wilmore and Williams could come home aboard a Crew Dragon spacecraft rather than Starliner. Due to the critical importance of this mission, Ars is sharing what we know as of Thursday afternoon.

One informed source said it was greater than a 50-50 chance that the crew would come back on Dragon. Another source said it was significantly more likely than not they would. To be clear, NASA has not made a final decision. This probably will not happen until at least next week. It is likely that Jim Free, NASA’s associate administrator, will make the call.

Asked if it was now more likely than not that Starliner’s crew would return on Dragon, NASA spokesperson Josh Finch told Ars on Thursday evening, “NASA is evaluating all options for the return of agency astronauts Butch Wilmore and Suni Williams from the International Space Station as safely as possible. No decisions have been made, and the agency will continue to provide updates on its planning.”

Putting Together Puzzle Pieces

What follows are some data points that Ars can confidently report based on multiple sources:
- NASA keeps delaying a decision. A Flight Readiness Review meeting had been scheduled for today, August 1, several days in advance. However, it was canceled. Instead, NASA put out a vague blog update on Thursday stating, “Following the completion of Starliner’s return planning, which is expected to continue into next week, more information will be shared about the agency’s return readiness review preparations and subsequent media briefing.” So maybe the meeting will take place next week.
- NASA issued a $266,678 task award to SpaceX on July 14 for a “special study for emergency response.” NASA said this study was not directly related to Starliner’s problems, but two sources told Ars it really was. Although the study entailed work on flying more than four crew members home on Crew Dragon—a scenario related to Frank Rubio and the Soyuz MS-22 leaks—it also allowed SpaceX to study flying Dragon home with six passengers, a regular crew complement in addition to Wilmore and Williams.
- SpaceX has been actively working on a scenario in which two or four astronauts launch on board Crew 9. (A normal crew is four) This mission has a nominal launch date of August 18, but it could well be delayed. SpaceX has already identified flight suits that would fit Wilmore and Williams, allowing them to fly home on the Crew-8 spacecraft (presently docked to the space station) or the Crew-9 vehicle. It is unclear how crews would be assigned to the two Dragon return flights. It is possible, if four astronauts launch on Crew 9, that five people could fly home on each of the two Dragons.
- Two sources told Ars that in meetings this week at NASA field centers, there have been vigorous discussions about whether or not to fly crew home on Starliner. Multiple groups remain “no” on Starliner as of Wednesday. It is unclear how this will be resolved. Some engineers believe that if there are questions about Starliner, then NASA should opt for the safe course—flying on Crew Dragon, which has safely launched 13 times and landed 12 times.
The Toughest of Calls

NASA officials face a difficult decision. Because there is still at least a small risk to flying Starliner in its present condition, the space agency and Boeing have tested the thrusters as thoroughly as possible while the spacecraft is docked to the space station. This testing was intended to “buy down” these risks. But while the data is good, it has not addressed all of NASA’s concerns.

So what will the space agency do? Starliner probably could make it back to Earth safely. But there appears to be some reasonable doubt that Starliner will come back safely. If NASA defers to its fallback plan, flying on Dragon, it may spell the end of the Starliner program. During the development and testing of Starliner, the company has already lost $1.6 billion. Reflying a crew test flight mission, which likely would be necessary should Starliner return autonomously, would cost much more. Boeing might opt to cancel Starliner and leave NASA with just a single provider of crew transportation. That would be painful for both NASA and Boeing.

But the alternative—Starliner not coming home safely with the crew inside—is far, far worse. This is the risk-reward decision that Free, Stich, and other NASA officials ultimately must balance in the coming days.

This story originally appeared on Ars Technica.
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August 3, 2024
Pooping on the Moon Is a Messy Business

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In addition to raising these legal and ethical quandaries, the Apollo waste bags have also inspired exciting scientific questions. How long did those bagged microbes last on the Moon? Did exposure to such unforgiving conditions prompt any mutations or adaptations? Since all species on Earth descend from microbes, this line of research would shed new light on the great mysteries of how and where life emerges in the universe. Answers to some of the most profound and ancient questions about our place in the cosmos may indeed be waiting in Neil Armstrong’s 55-year-old spent diapers.

“We are this multiplicity,” says Katherine Sammler, a human geographer at the University of Twente in the Netherlands, who has written about waste management in space through the lens of critical social theory. “We bring with us nonhuman passengers, like microbes and bacteria, as well as our own bodies and the things that go in and out of them. We have to think about the passengers that come with us and their experience of gravity and radiation on the moon.” The bags of waste would be rich sites for doing research, she adds. “What’s there? What’s left?”

In his mission concept, Lupisella proposes answering some of those questions by conducting biomolecular sequencing, among other experiments, on samples of Apollo astronaut poop. These efforts could potentially reveal whether the microbes experienced an altered rate of genetic mutations after being marooned on the Moon, which hypothetically could provide an adaptive advantage. Lupisella is also curious about whether any microbial spores in the bags could be revived in the right conditions.

“We already know life outside humans is robust, and can survive weird environments, but if the human microbiome can survive in those environments, like say on the Moon, that’s even more of a strong indicator of how tenacious life can be,” Lupisella says. “It would be another data point that says it’s a little bit easier to believe that life can exist in lots of places throughout the galaxy, solar system, and universe at large.”

Astronauts have often reported that the number one question they receive from schoolchildren is how they go to the bathroom in space. It’s a simple query that exposes a complex and ever-evolving set of challenges, many of which remain unresolved. It’s not clear that we will ever unlock satisfying solutions to these problems, but the ongoing effort to confront the legal, ethical, and practical obstacles of waste management in space will yield returns back here on Earth as well.

“I’m so excited about working on space issues, because we do have an opportunity to do better,” de Zwart says. “We should be going in a way that is sustainable and responsible. We should be thinking about how to minimize waste. Of course, if you can crack that nut for space, then it’s going to have massive benefits on Earth, so that we can help our game here about waste management and disposal.”

For instance, billions of people on Earth do not have access to safe sanitation services, a situation that has galvanized campaigns to build more innovative toilets and sewage systems. Meanwhile, growing numbers of livestock worldwide, and the billions of tons of feces they produce each year, are straining waste management programs. Wastewater frequently pollutes environments and exposes humans to health risks, including respiratory illnesses or waste-related pathogens. Wastewater systems currently contribute to greenhouse gas emissions, while the effects of climate change, including extreme weather events like floods or hurricanes, impose more stress on waste infrastructure.

“Perhaps humanity can avoid the worst effects of global climate change by embracing what even the military-industrial complex determined was an absolutely necessity to any spacecraft, namely a bioregenerative life support system,” Munns and Nickelsen say in their book.

“In writing a book about what people have done with their shit in space, we have also written a book that speaks to the problem of what people have to do with their shit on Earth,” they conclude.

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June 25, 2024
Starliner Faces an Indefinite Wait in Space While NASA Investigates Its Faults

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In an update released late Friday evening, NASA said it was “adjusting” the date of the Starliner spacecraft’s return to Earth from June 26 to an unspecified time in July.

The announcement followed two days of long meetings to review the readiness of the spacecraft, developed by Boeing, to fly NASA astronauts Butch Wilmore and Suni Williams to Earth. According to sources, these meetings included high-level participation from senior leaders at the agency, including associate administrator Jim Free.

This “Crew Flight Test,” which launched on June 5 atop an Atlas V rocket, was originally due to undock and return to Earth on June 14. However, as engineers from NASA and Boeing studied data from the vehicle’s problematic flight to the International Space Station, they have waved off several return opportunities.

On Friday night they did so again, citing the need to spend more time reviewing data.

“Taking Our Time”

“We are taking our time and following our standard mission management team process,” said Steve Stich, manager of NASA’s Commercial Crew Program, in the NASA update. “We are letting the data drive our decision making relative to managing the small helium system leaks and thruster performance we observed during rendezvous and docking.”

Just a few days ago, on Tuesday, officials from NASA and Boeing set a return date to Earth for June 26. But that was before a series of meetings on Thursday and Friday during which mission managers were to review findings about two significant issues with the Starliner spacecraft: five separate leaks in the helium system that pressurizes Starliner’s propulsion system and the failure of five of the vehicle’s 28 reaction-control system thrusters as Starliner approached the station.

The NASA update did not provide any information about deliberations during these meetings, but it is clear that the agency’s leaders were not able to get comfortable with all contingencies that Wilmore and Williams might encounter during a return flight to Earth, including safely undocking from the space station, maneuvering away, performing a de-orbit burn, separating the crew capsule from the service module, and then flying through the planet’s atmosphere before landing under parachutes in a New Mexico desert.

Spacecraft Has a 45-Day Limit

Now, the NASA and Boeing engineering teams will take some more time. Sources said NASA considered June 30 as a possible return date, but the agency is also keen to perform a pair of spacewalks outside the station. These spacewalks, presently planned for June 24 and July 2, will now go ahead. Starliner will make its return to Earth sometime afterward, likely no earlier than the July 4 holiday.

“We are strategically using the extra time to clear a path for some critical station activities while completing readiness for Butch and Suni’s return on Starliner and gaining valuable insight into the system upgrades we will want to make for post-certification missions,” Stich said.

In some sense, it is helpful for NASA and Boeing to have Starliner docked to the space station for a longer period of time. They can gather more data about the performance of the vehicle on long-duration missions—eventually Starliner will fly operational missions that will enable astronauts to stay on orbit for six months at a time.

However, this vehicle is only rated for a 45-day stay at the space station, and that clock began ticking on June 6. Moreover, it is not optimal that NASA feels the need to continue delaying the vehicle to get comfortable with its performance on the return journey to Earth. During a pair of news conferences since Starliner docked to the station, officials have downplayed the overall seriousness of these issues—repeatedly saying Starliner is cleared to come home “in case of an emergency.” But they have yet to fully explain why they are not yet comfortable with releasing Starliner to fly back to Earth under normal circumstances.

This story originally appeared on Ars Technica.

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June 23, 2024
Is an old NASA probe about to redraw the frontier of the solar system?

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NASA’s New Horizons spacecraft is hurtling out of the solar system at an incredible speed. It is currently about 8 billion kilometres from the sun, and by the time you finish reading this story, it will have sped thousands of kilometres further into the frigid gloom. It is lonely out there. Even the giant planet Jupiter is but a tiny speck.

New Horizons is mainly known for giving us our first proper look at the dwarf planet Pluto in 2015. Until then, we had only seen it as a blurry smudge. It has also taught us much about the solar system’s outer reaches and the small, frozen worlds that float there. “It’s really been an Alice in Wonderland kind of story,” says Alan Stern, the principal investigator of the mission. “It’s been dreamlike and we’ve discovered wonderful things.”

However, the dream isn’t over yet because New Horizons may be poised for a surprise final act. In early 2024, one of its detectors recorded an unexpected uptick in the amount of dust it was encountering. Since that material could have been created in collisions between rock fragments, astronomers now wonder if there are many objects beyond the rubble-strewn Kuiper belt often considered the edge of the solar system. If so, our system’s boundaries will need to be redrawn and our models of how it formed thrown into doubt.

Stern and his colleagues are obviously keen to take advantage of their probe’s unique position to learn more about this unexplored wilderness while they still can. “It’s an…

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June 19, 2024
NASA’s Quest to Touch the Sun

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The original version of this story appeared in Quanta Magazine.

Our sun is the best-observed star in the entire universe.

We see its light every day. For centuries, scientists have tracked the dark spots dappling its radiant face, while in recent decades, telescopes in space and on Earth have scrutinized sunbeams in wavelengths spanning the electromagnetic spectrum. Experiments have also sniffed the sun’s atmosphere, captured puffs of the solar wind, collected solar neutrinos and high-energy particles, and mapped our star’s magnetic field—or tried to, since we have yet to really observe the polar regions that are key to learning about the sun’s inner magnetic structure.

For all that scrutiny, however, one crucial question remained embarrassingly unsolved. At its surface, the sun is a toasty 6,000 degrees Celsius. But the outer layers of its atmosphere, called the corona, can be a blistering—and perplexing—1 million degrees hotter.

You can see that searing sheath of gas during a total solar eclipse, as happened on April 8 above a swath of North America. If you were in the path of totality, you could see the corona as a glowing halo around the moon-shadowed sun.

This year, that halo looked different than the one that appeared during the last North American eclipse, in 2017. Not only is the sun more active now, but you were looking at a structure that we—the scientists who study our home star—have finally come to understand. Observing the sun from afar wasn’t good enough for us to grasp what heats the corona. To solve this and other mysteries, we needed a sun-grazing space probe.

That spacecraft—NASA’s Parker Solar Probe—launched in 2018. As it loops around the sun, dipping in and out of the solar corona, it has collected data that shows us how small-scale magnetic activity within the solar atmosphere makes the solar corona almost inconceivably hot.

From Surface to Sheath

To begin to understand that roasting corona, we need to consider magnetic fields.

The sun’s magnetic engine, called the solar dynamo, lies about 200,000 kilometers beneath the sun’s surface. As it churns, that engine drives solar activity, which waxes and wanes over periods of roughly 11 years. When the sun is more active, solar flares, sunspots, and outbursts increase in intensity and frequency (as is happening now, near solar maximum).

At the sun’s surface, magnetic fields accumulate at the boundaries of churning convective cells, known as supergranules, which look like bubbles in a pan of boiling oil on the stove. The constantly boiling solar surface concentrates and strengthens those magnetic fields at the cells’ edges. Those amplified fields then launch transient jets and nanoflares as they interact with solar plasma.

Courtesy of NSO/NSF/AURA/Quanta Magazine

CAPTION: These churning convective cells on the sun’s surface, each approximately the size of the state of Texas, are closely connected to the magnetic activity that heats the sun’s corona.
CREDIT: NSO/NSF/AURA

Magnetic fields can also erupt through the sun’s surface and produce larger-scale phenomena. In regions where the field is strong, you see dark sunspots and giant magnetic loops. In most places, especially in the lower solar corona and near sunspots, these magnetic arcs are “closed,” with both ends attached to the sun. These closed loops come in various sizes—from minuscule ones to the dramatic, blazing arcs seen during eclipses.

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May 12, 2024
How to Watch the Boeing Starliner Launch

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It’s been a rough few years for Boeing, but now the company is about to fly closer to the sun than ever before. After nearly a decade of development and delays, the first crewed launch of the Boeing Starliner spacecraft is happening today. Here’s how to watch it live.

The launch is a jointly planned event between Boeing and NASA, and is scheduled for Monday, May 6, at 10:34 pm EDT, 7:34 PDT. You can watch the livestream of the launch a few different ways. It will stream on NASA’s official website and YouTube channel, as well as on NASA+, the agency’s subscription service. If you’re on mobile, the stream is also available on the NASA app. You can also watch it right here.

The livestream starts about four hours before the planned launch time, at 6:30 pm Eastern, 3:30 Pacific.

The launch of the Starliner is a long time coming. With this highly anticipated liftoff, Boeing will officially be the second company (after SpaceX) to partner with NASA to carry humans into space. The Starliner will be crewed by NASA astronauts Suni Williams and Butch Wilmore, who will head to the International Space Station. The plan is for the astronauts to remain there for a week or so, then return to planet Earth, reentering the atmosphere aboard the same craft and then landing under parachutes.

If this mission succeeds without a hitch, it will also likely be a welcome hit of good news for the troubled aviation company. Boeing has drawn a lot of presumably unwanted attention in recent months, as an array of technical malfunctions on its commercial airline flights have terrified travelers and made headlines. These events come soon after two of Boeing’s 737 Max planes crashed in 2018 and 2019. Clearly, Boeing is eager to claw back some public goodwill, and write a whole new chapter centered around a future of bringing more people into space.

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May 6, 2024
Boeing’s Starliner Is Finally Ready to Launch a NASA Crew Into Space

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“It fits in with the general narrative of Boeing having lost its way,” says McDowell.

Starliner, like Crew Dragon, is a capsule-shaped spacecraft like the Apollo missions of old. Capable of carrying up to seven astronauts, the spacecraft is largely autonomous, requiring major input only in the event of an emergency. During the test mission beginning tonight, Wilmore and Williams will test out this eventuality, purposefully pointing the spacecraft off course to ensure they can manually get it back on track, as well as assessing the spacecraft’s general life support and navigation systems. While docked to the space station the vehicle will be put through further tests, including practising using it as a lifeboat in case astronauts needed to evacuate the ISS.

Starliner is reusable, with Boeing saying it can be flown on up to 10 missions. The spacecraft sports no toilet—unlike Crew Dragon—and has about the same liveable volume as an SUV, making for a relatively cozy rise to and from orbit. It has physical hand controls and switches for the astronauts to control the spacecraft, unlike the touch screens used inside Crew Dragon. On its return home, a heat shield keeps the occupants safe from temperatures of some 3,000 degrees Fahrenheit, before the vehicle descends under parachute and finally touches down, with the help of air bags to cushion the fall, in one of several desert landing sites in the US.

Boeing is contracted with NASA to launch Starliner six times to the ISS after this test mission, each time carrying four or five astronauts along with cargo for six-month stays aboard the station. The spacecraft will alternate its missions with Crew Dragon, one launching around February and one around August each year. Having that redundancy is hugely beneficial, says NASA’s Steven Siceloff, public affairs specialist at NASA’s Kennedy Space Center. “This way, if a technical issue does come up with one vehicle, it does not mean that the space station is on its own for a while,” he says. “It means that there’s alternatives.”

Laura Forczyk, founder of the space consulting firm Astralytical, notes that redundancy is “especially important now because of the unreliability of Russia.” NASA and the Russian space agency, Roscosmos, continue to cooperate on the ISS program for now, including sharing seats between Russia’s Soyuz vehicle, Crew Dragon, and now Starliner, despite the embittered political situation between the two nations.

But beyond these six missions Boeing currently has no publicized flights planned for Starliner. “If this was SpaceX, you’d already have Musk talking about three or four contracts that he had in line with famous people,” says McDowell. With the ISS also set to be deorbited in 2030, this could mean Starliner—despite a decade of development and billions of dollars spent—faces the prospect of flying only a handful of times. “We don’t know whether Boeing has the capacity to do additional commercial missions at this time,” says Forczyk.

NASA has been trying to spur the development of new commercial space stations, in the same manner as this commercial crew program, in the hopes they can fill the orbital research void left when the ISS ends. These commercial stations could be destinations for Starliner and Crew Dragon, if they come to fruition, but the exact appetite for this endeavor remains uncertain for now. “Is there enough of a market to sustain two entities doing this?” says McDowell. “I remain skeptical of commercial space stations. But if they do succeed, you’re going to want multiple options to get up and down.”

Before it grapples with that future, Boeing will simply be hoping for a smooth and successful first crewed flight of Starliner. Once it’s finally in the skies with humans on board, the spacecraft can start to play the role it has long been touted for.

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May 6, 2024
Boeing’s Starliner spacecraft is about to make its first crewed flight

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Boeing’s Starliner spacecraft approaching the International Space Station

NASA

Boeing’s Starliner capsule is finally making its first crewed flight. On 6 May, it will launch atop an Atlas V rocket from Cape Canaveral in Florida. If the launch goes to plan, Starliner and its two passengers will arrive at the International Space Station (ISS) on 8 May.

Starliner has been in the works for more than a decade, but its first test flight didn’t take place until 2019. That flight reached orbit, but software issues prevented it from meeting up with the ISS. A second uncrewed test flight in 2022 was successful, setting the stage for the first crewed test.

The two test astronauts aboard Starliner are Butch Wilmore and Sunita Williams, each of whom has already been to the ISS twice before. The plan is for them to stay aboard the ISS for a week before returning to Earth.

The goal of this mission is to prove that Starliner is a safe option for transporting crew to and from the ISS, so most of its objectives involve testing out the spacecraft and its software. This is also the first time the Atlas V rocket has been used for a crewed mission. If all goes well, Starliner will be authorised for operation and begin making annual crewed flights.

NASA awarded Boeing the contract to use Starliner as a shuttle to the ISS in 2014, at the same time as a similar contract was awarded to SpaceX for its Dragon capsule. Boeing has lagged behind Dragon, which made its first crewed flight in 2020 and is now on its eighth operational mission.

When both are operational, it will give NASA a choice between rides to the ISS, which has not been the case since the retirement of the Space Shuttle in 2011. “This will give us that additional capability, because we always look for a backup,” NASA administrator Bill Nelson said in a 3 May press briefing. SpaceX has dominated crewed space flight in the US for years, so this may be the beginning of a broader playing field.

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May 6, 2024
Boeing’s Starliner spacecraft launch delayed due to rocket fault

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Boeing’s Starliner spacecraft approaching the International Space Station in 2022

NASA

Boeing’s Starliner capsule will have to wait for its first crewed flight, as a 6 May launch from Cape Canaveral in Florida was called off due to an issue with the Atlas V rocket. NASA has not yet announced a new date for the launch, but when it does go ahead Starliner and its two passengers will head for the International Space Station (ISS).

Starliner has been in the works for more than a decade, but its first test flight didn’t take place until 2019. That flight reached orbit, but software issues prevented it from meeting up with the ISS. A second uncrewed test flight in 2022 was successful, setting the stage for the first crewed test.

The two test astronauts aboard Starliner are Butch Wilmore and Sunita Williams, each of whom has already been to the ISS twice before. The plan is for them to stay aboard the ISS for a week before returning to Earth.

The goal of this mission is to prove that Starliner is a safe option for transporting crew to and from the ISS, so most of its objectives involve testing out the spacecraft and its software. This is also the first time the Atlas V rocket has been used for a crewed mission. If all goes well, Starliner will be authorised for operation and begin making annual crewed flights.

NASA awarded Boeing the contract to use Starliner as a shuttle to the ISS in 2014, at the same time as a similar contract was awarded to SpaceX for its Dragon capsule. Boeing has lagged behind Dragon, which made its first crewed flight in 2020 and is now on its eighth operational mission.

When both are operational, it will give NASA a choice between rides to the ISS, which has not been the case since the retirement of the space shuttle in 2011. “This will give us that additional capability, because we always look for a backup,” NASA administrator Bill Nelson said in a 3 May press briefing. SpaceX has dominated crewed space flight in the US for years, so this may be the beginning of a broader playing field.

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May 6, 2024
How NASA Repaired Voyager 1 From 15 Billion Miles Away

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Throughout the five months of troubleshooting, Voyager’s ground team continued to receive signals indicating the spacecraft was still alive. But until Saturday, they lacked insight into specific details about the status of Voyager 1.

“It’s pretty much just the way we left it,” Spilker said. “We’re still in the initial phases of analyzing all of the channels and looking at their trends. Some of the temperatures went down a little bit with this period of time that’s gone on, but we’re pretty much seeing everything we had hoped for. And that’s always good news.”

Relocating Code

Through their investigation, Voyager’s ground team discovered that a single chip responsible for storing a portion of the FDS memory had stopped working, probably due to either a cosmic ray hit or a failure of aging hardware. This affected some of the computer’s software code.

“That took out a section of memory,” Spilker said. “What they have to do is relocate that code into a different portion of the memory, and then make sure that anything that uses those codes, those subroutines, know to go to the new location of memory, for access and to run it.”

Only about 3 percent of the FDS memory was corrupted by the bad chip, so engineers needed to transplant that code into another part of the memory bank. But no single location is large enough to hold the section of code in its entirety, NASA said.

So the Voyager team divided the code into sections for storage in different places in the FDS. This wasn’t just a copy-and-paste job. Engineers needed to modify some of the code to make sure it will all work together. “Any references to the location of that code in other parts of the FDS memory needed to be updated as well,” NASA said in a statement.

Newer NASA missions have hardware and software simulators on the ground, where engineers can test new procedures to make sure they do no harm when they uplink commands to the real spacecraft. Due to its age, Voyager doesn’t have any ground simulators, and much of the mission’s original design documentation remains in paper form and hasn’t been digitized.

“It was really eyes-only to look at the code,” Spilker said. “So we had to triple check. Everybody was looking through and making sure we had all of the links coming together.”

This was just the first step in restoring Voyager 1 to full functionality. “We were pretty sure it would work, but until it actually happened, we didn’t know 100 percent for sure,” Spilker said.

“The reason we didn’t do everything in one step is that there was a very limited amount of memory we could find quickly, so we prioritized one data mode (the engineering data mode), and relocated only the code to restore that mode,” said Jeff Mellstrom, a JPL engineer who leads the Voyager 1 “tiger team” tasked with overcoming this problem.

“The next step, to relocate the remaining three actively used science data modes, is essentially the same,” Mellstrom said in a written response to Ars. “The main difference is the available memory constraint is now even tighter. We have ideas where we could relocate the code, but we haven’t yet fully assessed the options or made a decision. These are the first steps we will start this week.”

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April 24, 2024