[Space] Space Launch System, SLS - Page 11

On Halloween, NASA posted a document that provides some perspective on the agency's long-term plans for the Space Launch System rocket. This is the agency's titanic booster that has been under development since 2010, has an annual budget of more than $2 billion, and will not fly before at least 2021. The new document, known as a Justification for Other Than Full and Open Competition, explains why NASA rejected a lower-cost version of an upper stage for its rocket.

Early on, the space agency opted to build the large SLS rocket in phases. The initial version, Block 1, would have a placeholder upper stage. As a result, this initial variant of the rocket would be somewhat limited in its capabilities and only marginally more powerful than private rockets—most notably SpaceX's Falcon Heavy and Blue Origin's New Glenn boosters—developed without the deep pockets of US taxpayers.

The much more capable Block 1b of the SLS rocket will stand apart from these private rockets. With its more powerful second stage, known as the Exploration Upper Stage, it will more than double the lift capacity of these private rockets. Additionally, it will have the capability to launch both large amounts of cargo and the crewed Orion spacecraft at the same time.

At the outset of the program, NASA chose Boeing to build both the core stage of the SLS rocket, as well as the Exploration Upper Stage. In recent years, Congress has appropriated hundreds of millions of dollars for the agency and Boeing to design this new upper stage to fit on top of the SLS rocket. The agency has yet to move into development of the upper stage, however.

There are several reasons for this. NASA wants Boeing to finish the SLS rocket's core stage first, as it is already four years late. Moreover, because of Boeing's performance on the core stage and projected costs of the Exploration Upper Stage, the agency was curious if there were other aerospace companies interested in building a powerful upper stage for the SLS rocket.

Two years ago this frustration, in part, led NASA to issue a request for industry to provide a "low-cost replacement" for the RL-10 rocket engine that powered the Exploration Upper Stage, as well as perhaps an entirely new stage itself. An agency spokesperson said at the time the request sought to "open up the field of possible responses" and reduce costs of the SLS rocket's proposed upper stage.

Since that time, the issue of the Exploration Upper Stage has largely simmered behind the scenes. The new document released on Halloween, however, provides some clarity for what happened. And instead of opening upper stage bidding into a formal bidding process, NASA decided to stick with Boeing's version of the Exploration Upper Stage. Because this was a non-competitive process, NASA had to justify it with the new document.

After the Senate Appropriations Committee released its fiscal year 2020 budget bill in September, the White House Office of Management and Budget responded with a letter to share some "additional views" on the process. This letter (see a copy), dated October 23 and signed by acting director of the White House budget office Russell Vought, provides some insight into NASA's large Space Launch System rocket.

Congress has mandated that NASA use the more costly SLS booster to launch the ambitious Europa Clipper mission to Jupiter in the early 2020s, while the White House prefers the agency to fly on a much-less-expensive commercial rocket. In a section discussing the Clipper mission, Vought's letter includes a cost estimate to build and fly a single SLS rocket in a given year—more than $2 billion—which NASA has not previously specified.

"The Europa mission could be launched by a commercial rocket," Vought wrote to the chairman of the Senate Appropriations Committee, Alabama Republican Richard Shelby. "At an estimated cost of over $2 billion per launch for the SLS once development is complete, the use of a commercial launch vehicle would provide over $1.5 billion in cost savings. The Administration urges the Congress to provide NASA the flexibility called for by the NASA Inspector General."

Independent estimates have pegged the SLS cost this high, but NASA has never admitted it. A $2 billion cost to launch one SLS rocket a year raises significant questions about the sustainability of such an exploration program—the government killed the similarly sized Saturn V rocket in the early 1970s because of similarly unsustainable costs.

The letter also references a report published by NASA's Inspector General Paul Martin last May, which recommended that NASA scientists and engineers, rather than Congress, choose the best rocket for their science mission to Jupiter's Moon Europa. This report, however, placed a much lower cost estimate on the SLS rocket. It stated that, "NASA officials estimate the third SLS Block 1 launch vehicle’s marginal cost will be at least $876 million."

This discrepancy can likely be explained by the difference between marginal costs and marginal plus fixed costs. Martin's estimate is for "marginal" cost alone, meaning how much it would cost NASA to build an additional rocket in a given year. This likely does not apply to the Europa Clipper mission, however, as NASA would like to launch the Clipper spacecraft in 2023 or 2024, a time when the SLS rocket's core stage contractor, Boeing, will probably not be capable of building more than one booster a year.

The real cost for an SLS rocket should therefore include fixed costs—such factory space at NASA's Michoud Assembly in Louisiana, the workforce, and all of the other costs beyond a rocket's metal and other physical components. In other words, if you are only capable of building and flying one rocket a year, the total price must include fixed and marginal costs, which brings the SLS cost to "over $2 billion."

At an estimated cost of over $2 billion per launch for the SLS once development is complete, the use of a commercial launch vehicle would provide over $1.5 billion in cost savings.

NASA is close to finalizing a plan to land humans on the Moon in 2024 and is expected to publicly discuss it next month. While the space agency has not released its revised strategy publicly, a recently updated "mission manifest" for the Space Launch System rocket may provide some clues about the new Artemis Program.

According to a planning document circulated at NASA's Marshall Space Flight Center this week, titled "Moon 2024 Mission Manifest," the space agency has set target launch dates for its first 10 Artemis Moon missions. In doing so, the agency has shaken up the order of launches and emphasized the use of NASA's Space Launch System in the lunar return.

The document confirms an earlier report that the first Artemis mission to test SLS rocket will take place no earlier than April 2021. It also adds an additional Artemis mission in the run-up to the first human landing at the South Pole in late 2024:

• April 2021: Artemis I, Uncrewed test flight of Orion on Block 1 of SLS
  
• January 2023: Artemis II, Crewed flight of Orion around Moon on Block 1 of SLS
  
• August 2024: Artemis III, Integrated lunar lander launched to Moon on Block 1B of SLS
  
• October 2024: Artemis IV, Crewed flight of Orion for human Moon landing on Block 1 of SLS
  
• September 2025: Science mission, Launch of Europa Clipper on Block 1 of SLS
  
• June 2026: Artemis V, Crewed flight of Orion to Moon on Block 1B of SLS
  
• June 2027: Science mission, Launch of Europa Lander on Block 1B of SLS
  
• August 2028: Artemis VI, Crewed flight of Orion to Moon on Block 1B of SLS
  
• February 2029: Artemis VII, Cargo mission to Moon on Block 2 of SLS
  
• August 2029: Artemis VIII, Crewed mission of Orion on Block 2 of SLS
  
• February 2030: Artemis IX, Cargo mission on Block 2 of SLS
  
• August 2030: Artemis X, Crew mission on Block 2 of SLS
  

NASA said Thursday evening this mission manifest does not accurately reflect its Artemis plans.

"The proposed timeline in this article has many inaccuracies," said Matthew Rydin, press secretary for NASA. "We are currently in a blackout period because multiple companies have proposed human lunar lander solutions. These selections will be made in the coming weeks. However, the plan represented in this article is not the NASA plan."

But based upon the document obtained by Ars and recent internal briefings by NASA Associate Administrator Doug Loverro, it does seem increasingly clear that NASA is moving away from its original Artemis plan, which involved the use of multiple rockets and assembly of a Human Landing System in orbit around the Moon.

Loverro shakes things up

After arriving at NASA in late 2019 as the agency's new chief of human spaceflight, Loverro kicked off an assessment of the Artemis Program. As constituted at the time, NASA's plan called for using a mix of commercial rockets to pre-position components of a human lander near the Moon at the "Lunar Gateway." Four astronauts would then launch on the SLS rocket to rendezvous at the Gateway; two would descend to the surface of the Moon in the lander, and two would remain in orbit.

For this assessment, about 60 people at the agency and from industry sought to determine the status of the program as it was currently structured. After the analysis, Loverro told staffers at NASA he had "concerns" about whether the existing plan would work. In particular, during internal briefings, Loverro expressed doubts about the remote assembly of elements of the lunar lander at the Gateway. He also wanted NASA engineers to make sure the Orion spacecraft, with crew on board, could dock to the lander without the Gateway.

The potential revision of this plan, which may entail the launch of an entire lunar lander on an upgraded version of the SLS rocket, is notable for several reasons. Perhaps most significantly, it would place primary responsibility for NASA's Moon program on the shoulders of Boeing. That company is building the core stage of the SLS rocket, as well as an upgraded upper stage—the Exploration Upper Stage—that would now be required for use by August 2024 on the Block 1B version of the SLS. In fact, it would be required to accelerate development of the beefier SLS rocket.

"Due to the increases in number of flights and configurations, and the need for (Block 1B) one year earlier, much of the analysis work must be performed in parallel, rather than phased in series," the Marshall Space Flight Center document notes. Marshall, located in northern Alabama, oversees development of the SLS rocket.

Boeing on the critical path

In addition to this, such a plan would necessitate building an extra SLS core stage before fall 2024–four instead of three. This appears to be a change of heart by NASA administrator Jim Bridenstine, who until now has said Boeing will have its hands full completing three core stages by that time.

A reliance on Boeing would come as the contractor is already struggling with both the SLS rocket and its Starliner spacecraft for NASA. Largely due to issues with the core stage, the SLS rocket will be delayed at least four years beyond its original launch date of December 2016, with billions of dollars in overruns. NASA's inspector general has characterized Boeing's execution on the SLS program as "poor." Moreover, Boeing's Starliner crew spacecraft had several significant software issues during its first flight in December 2019 and was unable to fly up to the International Space Station.

The new plan, if implemented, would substantially cut commercially developed rockets—such as SpaceX's Falcon Heavy and Blue Origin's New Glenn—back from the Artemis program. Previously, NASA had said it would launch elements of its Human Landing System on commercial rockets, because such vehicles cost much less than the estimated $2 billion rate per launch of the SLS vehicle. Now, perhaps, private rockets may be called upon to launch smaller pieces such as a lunar rover to the Moon's surface.

Lunar lander

The Marshall document does not specify the components of the Human Landing System that will be launched on the SLS rocket. NASA is still in a blackout period as it seeks to award preliminary contracts for the ascent, descent, and transfer modules of its Human Landing System. Those awards are likely to come some time in mid-March.

There are four known bidders for lander development contracts: teams led by Boeing, Blue Origin, and Dynetics, as well as a plan from SpaceX. Of those, only Boeing has proposed building a fully integrated lander that would be launched on the Block 1B version of its SLS rocket. However, other bidders would presumably be allowed to propose integrated landers to be launched on the SLS booster.

The SLS launch manifest only tells part of the story of the Artemis Program. It does not specify the role a Lunar Gateway would play, although at the very least it does appear that the Gateway is pushed off into the future after a Moon landing. In that sense, this plan appears to be similar to that proposed by the US House of Representatives in its H.R. 5666 NASA authorization legislation.

Charlie Bolden, a four-time astronaut, served as NASA administrator from mid-2009 through early 2017. During that time, he oversaw the creation and initial development of the agency's large Space Launch System rocket.

Although some NASA officials such as then-Deputy Director Lori Garver were wary of the rocket's costs—about $20 billion has now been poured into development of a launch vehicle based on existing technology—Bolden remained a defender of the large rocket, calling it a lynchpin of the agency's plans to send humans beyond low-Earth orbit, perhaps to the Moon or Mars. He also dismissed the efforts of commercial space companies like SpaceX to build comparable technology.

When I sat down with Bolden for an interview in 2014 at Johnson Space Center, I asked why NASA was investing so much in the SLS rocket when SpaceX was using its own funds to develop the lower-cost Falcon Heavy rocket. His response at the time: “Let’s be very honest. We don’t have a commercially available heavy-lift vehicle. The Falcon 9 Heavy may some day come about. It’s on the drawing board right now. SLS is real.”

Two years later, in 2016, Bolden said he still did not believe commercial companies were up to the task. "If you talk about launch vehicles, we believe our responsibility to the nation is to take care of things that normal people cannot do, or don’t want to do, like large launch vehicles," Bolden said. "I’m not a big fan of commercial investment in large launch vehicles just yet."

Since that time, a lot has changed. In February 2018, SpaceX launched the Falcon Heavy rocket for the first time. It has since flown successfully two more times, and it will play a role in NASA's future exploration plans. Meanwhile, the SLS rocket, originally due to launch in 2017, is now delayed until at least the end of 2021.

As a result of this, Bolden appears to have changed his mind. In an interview with Politico published Friday morning in the publication's Space newsletter, Bolden was asked what might happen during the next four years.

“SLS will go away," he said. "It could go away during a Biden administration or a next Trump administration… because at some point commercial entities are going to catch up. They are really going to build a heavy lift launch vehicle sort of like SLS that they will be able to fly for a much cheaper price than NASA can do SLS. That’s just the way it works.”

Bolden remains a popular and influential voice in the space community, but he no longer has a direct say in US space policy. Perhaps because he no longer has to answer to Congress for NASA budgets, he is also free to speak his mind. In any case, his comments reflect the general sentiment in the space community—at least outside of the traditional contractors like Boeing and Northrop Grumman who directly benefit from SLS development—that the SLS rocket will eventually go away.

View of SLS outside the bubble

The Falcon Heavy is not as capable as the SLS rocket, but its success has clearly demonstrated that private companies can build large, powerful rockets. Moreover, it's not just SpaceX, but also Blue Origin with its New Glenn booster, that seeks to build heavy lift rockets with private money. And although they are rivals, SpaceX's Elon Musk and Blue Origin's Jeff Bezos both agree that rockets need to be capable of reuse to be viable. The SLS will cost about $2 billion to launch and then fall into the ocean.

If you're wondering what commercial space proponents really think about the SLS rocket due to its cost and expendability, it's this, which comes from a senior official at a new space company:

"If Santa Claus arrived, and said, 'I have good news. It now works and you can launch tomorrow. Everything's done. You're going to have a launch tomorrow.' ... It still isn't getting us to the Moon. Even if they achieve everything they aim for, it still does not get people to the Moon. It certainly does not get a base on the Moon and absolutely doesn't get humans to Mars."

When Congress conceived of the Space Launch System rocket in 2010 and directed NASA to build it, they were making two bets. First, they bet the new space companies such as SpaceX would fail. This was a reasonable bet back then, as SpaceX had lost most of the rockets it had tried to launch into space. Second, they bet that traditional companies like Boeing would be better at building big rockets.

The congressional lawmakers who created SLS—it began with Florida Senator Bill Nelson and Texas Senator Kay Bailey Hutchison, and they were soon joined by Alabama Senator Richard Shelby—lost both of those bets. So now, NASA is building a large, expendable rocket that has cost taxpayers tens of billions of dollars. Congress remains as committed as ever, both in budgets and public statements of support. However, the more that new rockets fly, the more difficult this support will be to maintain.

Ironically, NASA and the SLS prime contractor Boeing are no longer competing with the Falcon Heavy. SpaceX beat them two and a half years ago. Rather, NASA is competing with SpaceX's next rocket, the Super Heavy booster that will loft Starship into orbit. SpaceX has not even built a single segment of its Super Heavy rocket—which is larger than SLS, more powerful, vastly cheaper, and reusable—but it's possible that the vehicle makes an orbital launch before the decade-old SLS in 2021.

NASA’s newest moon rocket is powered not only by four RS-25 engines that, combined, unleash 2 million pounds of thrust, but by two solid fuel side boosters that burn six tons of propellant a second at such enormous temperatures that during a recent test fire in the Utah desert, the flames turned sand to glass.

When it launches, NASA’s Space Launch System rocket, a towering 322-foot behemoth — taller than the Statue of Liberty — would be the most powerful rocket ever flown, eclipsing both the Saturn V that flew astronauts to the moon and SpaceX’s Falcon Heavy, which has launched commercial and national security satellites as well as founder Elon Musk’s Tesla Roadster on a trip to Mars.

But as NASA moves toward the SLS’s first flight, putting the Orion spacecraft in orbit around the moon, it’s not the rocket’s engines that concern officials but the software that will control everything the rocket does, from setting its trajectory to opening individual valves to open and close.

Computing power has become as critical to rockets as the brute force that lifts them out of Earth’s atmosphere, especially rockets like the SLS, which is really an amalgamation of parts built by a variety of manufacturers: Boeing builds the rocket’s “core stage,” the main part of the vehicle. Lockheed Martin builds the Orion spacecraft. Aerojet Rocketdyne and Northrop Grumman are responsible for the RS-25 engines and the side boosters, respectively. And the United Launch Alliance handles the upper stage.

All of those components need to work together for a mission to be successful. But NASA’s Aerospace Safety Advisory Panel (ASAP) recently said it was concerned about the disjointed way the complicated system was being developed and tested.

At an ASAP meeting last month, Paul Hill, a member of the panel and a former flight and mission operations director at the agency, said the “panel has great concern about the end-to-end integrated test capability and plans, especially for flight software.”

Instead of one comprehensive avionics and software test to mimic flight, he said, there is “instead multiple and separate labs; emulators and simulations are being used to test subsets of the software.”

“As much as possible, flight systems should be developed for success, with the goal to test like you fly. In the same way that NASA’s operations teams train the way you fly and fly the way you train,” Hill said.

Also troubling to the safety panel was that NASA and its contractors appeared not to have taken “advantage of the lessons learned” from the botched flight last year of Boeing’s Starliner spacecraft, which suffered a pair of software errors that prevented it from docking with the International Space Station as planned and forced controllers to cut the mission short.

NASA has since said that it did a poor job of overseeing Boeing on the Starliner program, and has since vowed to have more rigorous reviews of its work, especially its software testing.

The SLS software concerns are the latest red flags for a program that has struggled to overcome a series of cost overruns and setbacks. A slew of government watchdog reports over the years have painted a troubling picture of mismanagement.

Three years ago, the NASA Inspector General reported in an audit that NASA had spent more than $15 billion on SLS, the Orion spacecraft and their associated ground systems between 2012 and 2016. It estimated the total would reach $23 billion.

The report chided Boeing, the main contractor, which it said “consistently underestimated the scope of the work to be performed and thus the size and skills of the workforce required.”

Another report, by the Government Accountability Office last year, found that despite Boeing’s poor performance, NASA continued to pay it tens of millions of dollars in “award fees” for scoring high on evaluations.

NASA says now that the program is finally on track, with the vehicle undergoing a series of rigorous tests known as the “Green Run” at the Stennis Space Center in Mississippi that will culminate with a “hot fire” — the ignition and eight-minute burn of its engines scheduled for later this year.

Then it would be moved to the Kennedy Space Center in Florida, ahead of its first launch, currently scheduled for late 2021. NASA administrator Jim Bridenstine said “all of the elements that we need for a successful 2024 moon landing are underway as part of the agency’s Artemis program. And we’re moving rapidly to achieve that goal” — a dramatic White House-ordered acceleration of the original timetable that foresaw a moon landing in 2028.

For that deadline to be achieved, however, the flight software has to work perfectly. The first test is expected to come late next year, when the SLS would fly for the first time in the Artemis I mission, putting the Orion spacecraft without any crews on board in orbit around the moon.

“When it all comes down to it, flight software is the functional integration piece of the rocket,” Dan Mitchell, NASA’s senior technical leader for SLS avionics and software engineering, said in an interview. “The rocket doesn’t fly without flight software. The software commands all the valves and the engines. It takes reasons of all the parameters inside the vehicle, the navigation and position information and uses all that information to control the fight.”

There was perhaps no better illustration of the significant role software plays in space flight, and how flaws in the coding can have severe consequences, than Starliner’s test flight.

Shortly after it reached orbit, the spacecraft, which had no astronauts on board, ran into trouble because the spacecraft’s flight computers were 11 hours off. With the spacecraft thinking it was at an entirely different point in the mission, it attempted to correct its course, burning precious fuel and forcing controllers to end the mission early without completing the main goal: docking with the International Space Station. Controllers later found another software problem that could have caused the service module to collide with the crew capsule after separation, potentially endangering astronauts, if any had been on board.

Boeing was able to diagnose the problem, send up a software fix and ultimately bring the spacecraft down safely. Later, Boeing said its testing of the software was deeply flawed, allowing the two problems to go undetected in the spacecraft’s one million lines of code. It was an admission reminiscent of the software problems that plagued its 737 Max airplane, which suffered two crashes that killed 346 people combined and remains grounded worldwide.

Boeing officials have said that during the test flight, the Starliner was pulling its time from the rocket. During testing, officials were mainly focused on making sure the two vehicles were communicating correctly, but cut short the test so that it never uncovered that the spacecraft was reading the wrong time.

If the test had continued, “we would have caught it,” John Mulholland said earlier this year, when he was the Starliner program manager for Boeing. He’s since transferred to Boeing’s space station program.

During the software test for the service module separation, Boeing didn’t use the actual hardware but rather an “emulator,” a computer system designed to mimic the service module. The problem was the emulator had the wrong thruster configuration programmed in at the time of the test, Mulholland said.

NASA officials in charge of the SLS program said they are confident the testing protocols for the SLS rocket and Orion spacecraft are far more robust. For starters, the program is set up differently. Boeing owns and operates the Starliner spacecraft and uses it to perform a service for NASA — namely flying its astronauts to the space station.

On the SLS program, by contrast, NASA owns and will operate the rocket, and is responsible for all the integrated testing.

Mitchell, the NASA senior technical leader, said the SLS team took the Starliner mishap “to heart.” As a result, they spent four days testing the various interfaces between the SLS and Orion, he said. “We methodically walked through requirement by requirement. ... It was a very, very detailed and fruitful interaction that we had across all the interfaces,” he said.

The review turned up one issue with how the rocket’s second stage interpreted data from the first stage, he said, but that “has been determined to be a benign issue” that doesn’t require any modifications at this time.

NASA pushed back on the safety panel’s findings, saying in a statement that “all software, hardware, and combination for every phase of the Artemis I mission is thoroughly tested and evaluated to ensure that it meets NASA’s strict safety requirements and is fully qualified for human spaceflight.”

The agency and its contractors are “conducting integrated end-to-end testing for the software, hardware, avionics and integrated systems needed to fly Artemis missions,” it said.

Once the vehicle is moved to the Kennedy Space Center, testing will continue with a “countdown demonstration and wet dress rehearsal [by fueling the rocket] with the rocket, spacecraft, and ground systems prior to the Artemis I launch.”

Speaking to reporters in October, John Shannon, a Boeing vice president who oversees the SLS program, said the core stage holds “the brains” of the rocket, the avionics, flight computers and “the systems to control the vehicle.”

But he said the company’s portion of software development and testing was limited to what’s called the “stage controller,” or “ground software that commands the vehicle itself.”

Shannon said the systems have been “completed, tested in integration facilities at [NASA’s] Marshall Space Flight Center. We’ve had independent verification and validation on it to show that it works well with the flight software and the stand controller software. And it’s all all ready to go.”

Engineers are racing to fix a failed piece of equipment on NASA’s future deep-space crew capsule Orion ahead of its first flight to space. It may require months of work to replace and fix. Right now, engineers at NASA and Orion’s primary contractor, Lockheed Martin, are trying to figure out the best way to fix the component and how much time the repairs are going to take.

In early November, engineers at Lockheed Martin working on Orion noticed that a power component inside the vehicle had failed, according to an internal email and an internal PowerPoint presentation seen by The Verge. The component is within one of the spacecraft’s eight power and data units, or PDUs. The PDUs are the “main power/data boxes,” for Orion according to the email, responsible for activating key systems that Orion needs during flight.

Orion is a critical part of NASA’s Artemis program, which aims to send the first woman and the next man to the Moon by 2024. The cone-shaped capsule is designed to launch on top of a future rocket called the Space Launch System, or SLS, a vehicle that NASA has been building for the last decade. To test out both of these systems’ capabilities, NASA plans to launch an uncrewed Orion capsule on top of the SLS on the rocket’s first flight in late 2021 — a mission called Artemis I.

While the SLS still has many key tests to undergo before that flight, the Orion capsule slated to fly on that first mission is mostly assembled, waiting in Florida at NASA’s Operation and Checkout Facility at Kennedy Space Center. NASA had planned to transfer the Orion capsule to the Multi-Payload Processing Facility (MPPF) at KSC on December 7th, though that rollout may be postponed due to this issue. When asked for a comment, NASA directed The Verge to a short blog post published today outlining the failure.

“While the PDU is still fully operational without this redundant channel we are swiftly trouble shooting the card while also continuing close-out activities on Orion,” a representative for Lockheed Martin said in a statement to The Verge. “We are fully committed to seeing Orion launch next year on its historic Artemis I mission to the Moon.

Replacing the PDU isn’t easy. The component is difficult to reach: it’s located inside an adapter that connects Orion to its service module — a cylindrical trunk that provides support, propulsion, and power for the capsule during its trip through space. To get to the PDU, Lockheed Martin could remove the Orion crew capsule from its service module, but it’s a lengthy process that could take up to a year. As many as nine months would be needed to take the vehicle apart and put it back together again, in addition to three months for subsequent testing, according to the presentation.

Lockheed has another option, but it’s never been done before and may carry extra risks, Lockheed Martin engineers acknowledge in their presentation. To do it, engineers would have to tunnel through the adapter’s exterior by removing some of the outer panels of the adapter to get to the PDU. The panels weren’t designed to be removed this way, but this scenario may only take up to four months to complete if engineers figure out a way to do it.

A third option is that Lockheed Martin and NASA could fly the Orion capsule as is. The PDU failed in such a way that it lost redundancy within the unit, so it can still function. But at a risk-averse agency like NASA, flying a vehicle without a backup plan is not exactly an attractive option. It’s still not clear what went wrong inside the unit, which was tested before it was installed on the spacecraft, according to a person familiar with the matter.

If engineers choose to remove Orion from its service module, the capsule’s first flight on the SLS may be delayed past its current date of November 2021. But the SLS has experienced its own set of delays: it was supposed to fly for the first time in 2017 but hasn’t done so yet. It’s not clear if the SLS itself will make the November 2021 flight date either; a key test of the rocket coming up at the end of the year has been pushed back, with no new target date set. So it’s possible that Lockheed Martin and NASA can fix Orion before the SLS is ready to fly.

Any further delays to Artemis I add uncertainty to NASA’s lunar landing timeline. NASA is hoping to land astronauts on the Moon by 2024, though many experts are skeptical that such a mission can be pulled off in time. Artemis I is vulnerable to other possible delays, but the component failure adds one more level of uncertainty to when the Orion and SLS combo will get off the ground.

Following a test readiness review on Monday, NASA is now targeting Saturday, Jan. 16, for the final test in the Green Run testing series for the core stage of the Space Launch System (SLS) rocket that will launch the agency’s Artemis I mission. NASA will host a media teleconference at 1 p.m. EST Tuesday, Jan.12, to discuss the test, known as the hot fire, which will take place at NASA’s Stennis Space Center near Bay St. Louis, Mississippi.

During the test, engineers will power up all the core stage systems, load more than 700,000 gallons of cryogenic, or supercold, propellant into the tanks and fire all four engines at the same time.

The Green Run test series is a comprehensive assessment of the rocket’s core stage prior to SLS launching Artemis missions to the Moon. The core stage includes the liquid hydrogen tank and liquid oxygen tank, four RS-25 engines, and the computers, electronics, and avionics that serve as the “brains” of the rocket. NASA has completed seven of the eight core stage Green Run tests, including loading and draining propellant for the first time during the most recent test, the wet dress rehearsal, on Dec. 20. During the upcoming hot fire test, all four engines will fire to simulate the stage’s operation during launch.

The bill would also require NASA to continue development of the "Exploration Upper Stage," which is a new, more powerful second stage for the agency's Space Launch System rocket. Moreover, the bill says this upper stage should be ready for use on the third launch of the rocket.

There's just one problem with this requirement—NASA says it doesn't need the Exploration Upper Stage to complete its early Artemis Moon missions. The first launches will use a commercially available upper stage, which is powerful enough to launch a crew of astronauts aboard the Orion spacecraft to the Moon.

This legislation therefore burdens NASA with the upper stage development—likely to cost about $10 billion and take five years—at a time when the agency is busy enough trying to complete the first Moon missions. And although they will not admit this publicly, some NASA engineers are not even sure they need the upper stage. If SpaceX's Starship vehicle is successful, it would be more powerful, cost less, and fly more frequently than the SLS rocket, even with its advanced upper stage.

It is not too difficult to see the hand of Boeing behind this legislative requirement, as the company has the prime contract to develop the Exploration Upper Stage.

Main propulsion test article

There is one other novel aspect of this legislation that really drives home its parochial bent. The Cantwell-Wicker amendment says NASA should "initiate development of a main propulsion test article for the integrated core stage propulsion elements of the Space Launch System, consistent with cost and schedule constraints, particularly for long-lead propulsion hardware needed for flight."

So what is this? It's basically a test article of the SLS rocket's core stage. Such an element, which NASA has not asked for, would effectively allow NASA and Boeing to perform tests on an SLS prototype at Stennis Space Center in Southern Mississippi in perpetuity.

The backstory to this proposal is that Wicker, the Mississippi senator, is not happy that NASA only planned to perform a series of "Green Run" tests at Stennis on the very first core stage. (NASA completed this core stage test in March and has since shipped the first SLS rocket to Florida). A single test, the agency reasoned, would be enough to validate the technology.

With this legislation, however, NASA could do more tests, keeping Wicker's center fully engaged and local contractors gainfully employed. Whether it would advance NASA's exploration efforts, however, is a far more dubious proposition.