It was not immediately clear why. A NASA spokesperson in Washington, DC, offered no comment on the updated guidance. Two sources indicated that it was plausible that private astronaut Jared Isaacman, whom President Trump has nominated to lead the space agency, asked for the cuts to be put on hold.
Although this could not be confirmed, it seems reasonable that Isaacman would want to retain some control over where cuts at the agency are made. Firing all probationary employees—which is the most expedient way to reduce the size of government—is a blunt instrument. It whacks new hires that the agency may have recruited for key positions, as well as high performers who earned promotions.
The reprieve in these terminations does not necessarily signal that NASA will escape significant budget or employment cuts in the coming months.
The administration could still seek to terminate probationary employees. In addition, Ars reported earlier that directors at the agency’s field centers have been told to prepare options for a “significant” reduction in force in the coming months. The scope of these cuts has not been defined, and it’s likely they would need to be negotiated with Congress.
Spread across NASA’s headquarters and 10 field centers, which dot the United States from sea to sea, the space agency has had a workforce of nearly 18,000 civil servants.
However, by the end of today, that number will have shrunk by about 10 percent since the beginning of the second Trump administration four weeks ago. And the world’s preeminent space agency may still face significant additional cuts.
According to sources, about 750 employees at NASA accepted the “fork in the road” offer to take deferred resignation from the space agency later this year. This sounds like a lot of people, but generally about 1,000 people leave the agency every year, so effectively, many of these people might just be getting paid to leave jobs they were already planning to exit from.
The culling of “probationary” employees will be more impactful. As it has done at other federal agencies, the Trump administration is generally firing federal employees who are in the “probationary” period of their employment, which includes new hires within the last one or two years or long-time employees who have moved into or been promoted into a new position. About 1,000 or slightly more employees at NASA were impacted by these cuts.
Adding up the deferred resignations and probationary cuts, the Trump White House has now trimmed about 10 percent of the agency’s workforce.
However, the cuts may not stop there. Two sources told Ars that directors at the agency’s field centers have been told to prepare options for a “significant” reduction in force in the coming months. The scope of these cuts has not been defined, and it’s possible they may not even happen, given that the White House must negotiate budgets for NASA and other agencies with the US Congress. But this directive for further reductions in force casts more uncertainty on an already demoralized workforce and signals that the Trump administration would like to make further cuts.
“When I see a picture like this, it is impossible not to feel energized about the future,” he wrote. “I think it is so important for people to understand the profound implications of sending humans to another planet.”
Among these, Isaacman cited the benefits of advancing state-of-the-art technologies including propulsion, habitability, power generation, in-situ resource utilization, and manufacturing.
“We will create systems, countermeasures, and pharmaceuticals to sustain human life in extreme conditions, addressing challenges like radiation and microgravity over extended durations,” he said. “These advancements will form the foundation for lower-cost, more frequent crewed and robotic missions across the solar system, creating a flywheel effect to accelerate world-changing discoveries.”
Additionally, Isaacman said taking the first steps toward humanity living beyond Earth was critical to the long-term survival of the species, and that such an achievement would inspire a new generation of scientific and technological leaders.
“Achieving such an outrageous endeavor—like landing American astronauts on another planet—will inspire generations of dreamers to build upon these accomplishments, set even bolder goals, and drive humankind’s greatest adventure forward,” he wrote.
Upon being asked about his thoughts about sending humans to Mars during the launch window in late 2028 or early 2029, Isaacman said he remains on the outside of NASA’s planning process for now. But he did say the United States should start to put serious effort toward sending humans to Mars.
“We should invest a reasonable amount of resources coupled with extreme work intensity and then make them a reality,” he wrote. “Even getting 90% there in the near term would set humankind on an incredible trajectory for the long term.”
The primary contractor for the Space Launch System rocket, Boeing, is preparing for the possibility that NASA cancels the long-running program.
On Friday, with less than an hour’s notice, David Dutcher, Boeing’s vice president and program manager for the SLS rocket, scheduled an all-hands meeting for the approximately 800 employees working on the program. The apparently scripted meeting lasted just six minutes, and Dutcher didn’t take questions.
During his remarks, Dutcher said Boeing’s contracts for the rocket could end in March and that the company was preparing for layoffs in case the contracts with the space agency were not renewed. “Cold and scripted” is how one person described Dutcher’s demeanor.
Giving a 60-day notice
The aerospace company, which is the primary contractor for the rocket’s large core stage, issued the notifications as part of the Worker Adjustment and Retraining Notification (or WARN) Act, which requires US employers with 100 or more full-time employees to provide a 60-day notice in advance of mass layoffs or plant closings.
“To align with revisions to the Artemis program and cost expectations, today we informed our Space Launch Systems team of the potential for approximately 400 fewer positions by April 2025,” a Boeing spokesperson told Ars. “This will require 60-day notices of involuntary layoff be issued to impacted employees in coming weeks, in accordance with the Worker Adjustment and Retraining Notification Act. We are working with our customer and seeking opportunities to redeploy employees across our company to minimize job losses and retain our talented teammates.”
The timing of Friday’s hastily called meeting aligns with the anticipated release of President Trump’s budget proposal for fiscal year 2026. This may not be an entire plan but rather a “skinny” budget that lays out a wish list of spending requests for Congress and some basic economic projections. Congress does not have to act on Trump’s budget priorities.
More data will likely reduce the chance of an impact to zero. If not, we have options.
Discovery images of asteroid 2024 YR4. Credit: ATLAS
Something in the sky captured the attention of astronomers in the final days of 2024. A telescope in Chile scanning the night sky detected a faint point of light, and it didn’t correspond to any of the thousands of known stars, comets, and asteroids in astronomers’ all-sky catalog.
The detection on December 27 came from one of a network of telescopes managed by the Asteroid Terrestrial-impact Last Alert System (ATLAS), a NASA-funded project to provide warning of asteroids on a collision course with Earth.
Within a few days, scientists gathered enough information on the asteroid—officially designated 2024 YR4—to determine that its orbit will bring it quite close to Earth in 2028, and then again in 2032. Astronomers ruled out any chance of an impact with Earth in 2028, but there’s a small chance the asteroid might hit our planet on December 22, 2032.
How small? The probability has fluctuated in recent days, but as of Thursday, NASA’s Center for Near Earth Object Studies estimated a 1.9 percent chance of an impact with Earth in 2032. The European Space Agency (ESA) put the probability at 1.8 percent. So as of now, NASA believes there’s a 1-in-53 chance of 2024 YR4 striking Earth. That’s about twice as likely as the lifetime risk of dying in a motor vehicle crash, according to the National Safety Council.
These numbers are slightly higher than the probabilities published last month, when ESA estimated a 1.2 percent chance of an impact. In a matter of weeks or months, the number will likely drop to zero.
No surprise here, according to ESA.
“It is important to remember that an asteroid’s impact probability often rises at first before quickly dropping to zero after additional observations,” ESA said in a press release. The agency released a short explainer video, embedded below, showing how an asteroid’s cone of uncertainty shrinks as scientists get a better idea of its trajectory.
Refining the risk
Scientists estimate that 2024 YR4 is between 130 to 300 feet (40 and 90 meters) wide, large enough to cause localized devastation near the impact site. The asteroid responsible for the Tunguska event of 1908, which leveled some 500 square miles (1,287 square kilometers) of forest in remote Siberia, was probably about the same size. The meteor that broke apart in the sky over Chelyabinsk, Russia, in 2013 was about 20 meters wide.
Astronomers use the Torino scale for measuring the risk of potential asteroid impacts. Asteroid 2024 YR4 is now rated at Level 3 on this scale, meaning it merits close attention from astronomers, the public, and government officials. This is the second time an asteroid has reached this level since the scale’s adoption in 1999. The other case happened in 2004, when asteroid Apophis briefly reached a Level 4 rating until further observations of the asteroid eliminated any chance of an impact with the Earth in 2029.
In the unlikely event that it impacts the Earth, an asteroid the size of 2024 YR4 could cause blast damage as far as 30 miles (50 kilometers) from the location of the impact or airburst if the object breaks apart in the atmosphere, according to the International Asteroid Warning Network (IAWN), established in the aftermath of the Chelyabinsk event.
The asteroid warning network is affiliated with the United Nations. Officials activate the IAWN when an asteroid bigger than 10 meters has a greater than 1 percent chance of striking Earth within the next 20 years. The risk of 2024 YR4 meets this threshold.
The red points on this image show the possible locations of asteroid 2024 YR4 on December 22, 2032, as projected by a Monte Carlo simulation. As this image shows, most of the simulations project the asteroid missing the Earth. Credit: ESA/Planetary Defense Office
Determining the asteroid’s exact size will be difficult. Scientists would need deep space radar observations, thermal infrared observations, or imagery from a spacecraft that could closely approach the asteroid, according to the IAWN. The asteroid won’t come close enough to Earth for deep space radar observations until shortly before its closest approach in 2032.
Astronomers need numerous observations to precisely plot an asteroid’s motion through the Solar System. Over time, these observations will reduce uncertainty and narrow the corridor the asteroid will follow as it comes near Earth.
Scientists already know a little about asteroid 2024 YR4’s orbit, which follows an elliptical path around the Sun. The orbit brings the asteroid inside of Earth’s orbit at its closest point to the Sun and then into the outer part of the asteroid belt when it is farthest from the Sun.
But there’s a complication in astronomers’ attempts to nail down the asteroid’s path. The object is currently moving away from Earth in almost a straight line. This makes it difficult to accurately determine its orbit by studying how its trajectory curves over time, according to ESA.
It also means observers will need to use larger telescopes to see the asteroid before it becomes too distant to see it from Earth in April. By the end of this year’s observing window, the asteroid warning network says the impact probability could increase to a couple tens of percent, or it could more likely drop back below the notification threshold (1 percent impact probability).
“It is possible that asteroid 2024 YR4 will fade from view before we are able to entirely rule out any chance of impact in 2032,” ESA said. “In this case, the asteroid will likely remain on ESA’s risk list until it becomes observable again in 2028.”
Planetary defenders
This means that public officials might need to start planning what to do later this year.
For the first time, an international board called the Space Mission Planning Advisory Group met this week to discuss what we can do to respond to the risk of an asteroid impact. This group, known as SMPAG, coordinates planning among representatives from the world’s space agencies, including NASA, ESA, China, and Russia.
The group decided on Monday to give astronomers a few more months to refine their estimates of the asteroid’s orbit before taking action. They will meet again in late April or early May or earlier if the impact risk increases significantly. If there’s still a greater than 1 percent probability of 2024 YR4 hitting the Earth, the group will issue a recommendation for further action to the United Nations Office for Outer Space Affairs.
So what are the options? If the data in a few months still shows that the asteroid poses a hazard to Earth, it will be time for the world’s space agencies to consider a deflection mission. NASA demonstrated its ability to alter the orbit of an asteroid in 2022 with a first-of-its-kind experiment in space. The mission, called DART, put a small spacecraft on a collision course with an asteroid two to four times larger than 2024 YR4.
The kinetic energy from the spacecraft’s death dive into the asteroid was enough to slightly nudge the object off its natural orbit around a nearby larger asteroid. This proved that an asteroid deflection mission could work if scientists have enough time to design and build it, an undertaking that took about five years for DART.
Italy’s LICIACube spacecraft snapped this image of asteroids Didymos (lower left) and Dimorphos (upper right) a few minutes after the impact of DART on September 26, 2022. Credit: ASI/NASA
A deflection mission is most effective well ahead of an asteroid’s potential encounter with the Earth, so it’s important not to wait until the last minute.
Fans of Hollywood movies know there’s a nuclear option for dealing with an asteroid coming toward us. The drawback of using a nuclear warhead is that it could shatter one large asteroid into many smaller objects, although recent research suggests a more distant nuclear explosion could produce enough X-ray radiation to push an asteroid off a collision course.
Waiting for additional observations in 2028 would leave little time to develop a deflection mission. Therefore, in the unlikely event that the risk of an impact rises over the next few months, it will be time for officials to start seriously considering the possibility of an intervention.
Even without a deflection, there’s plenty of time for government officials to do something here on Earth. It should be possible for authorities to evacuate any populations that might be affected by the asteroid.
The asteroid could devastate an area the size of a large city, but any impact is most likely to happen in a remote region or in the ocean. The risk corridor for 2024 YR4 extends from the eastern Pacific Ocean to northern South America, the Atlantic Ocean, Africa, the Arabian Sea, and South Asia.
There’s an old joke that dinosaurs went extinct because they didn’t have a space program. Whatever happens in 2032, we’re not at risk of extinction. However, occasions like this are exactly why most Americans think we should have a space program. A 2019 poll showed that 68 percent of Americans considered it very or extremely important for the space program to monitor asteroids, comets, or other objects from space that could strike the planet.
In contrast, about a quarter of those polled placed such importance on returning astronauts to the Moon or sending people to Mars. The cost of monitoring and deflecting asteroids is modest compared to the expensive undertakings of human missions to the Moon and Mars.
From taxpayers’ point of view, it seems this part of NASA offers the greatest bang for their buck.
Stephen Clark is a space reporter at Ars Technica, covering private space companies and the world’s space agencies. Stephen writes about the nexus of technology, science, policy, and business on and off the planet.
The US space agency said Wednesday it will host a live Twitch stream from the International Space Station on February 12.
NASA, which has 1.3 million followers on the live-streaming video service, has previously broadcast events on its Twitch channel. However, this will be the first time the agency has created an event specifically for Twitch.
During the live event, beginning at 11: 45 am ET (16: 45 UTC), viewers will hear from NASA astronaut Don Pettit, who is currently on board the space station, as well as Matt Dominick, who recently returned to Earth after the agency’s Crew-8 mission. Viewers will have the opportunity to ask questions about living in space.
Twitch is owned by Amazon, and it has become especially popular in the online gaming community for the ability to stream video games and chat with viewers.
Meeting people where they are
“We spoke with digital creators at TwitchCon about their desire for streams designed with their communities in mind, and we listened,” said Brittany Brown, director of the Office of Communications Digital and Technology Division. “In addition to our spacewalks, launches, and landings, we’ll host more Twitch-exclusive streams like this one. Twitch is one of the many digital platforms we use to reach new audiences and get them excited about all things space.”
Like a lot of the rest of the federal government right now, NASA is reeling during the first turbulent days of the Trump administration.
The last two weeks have brought a change in leadership in the form of interim administrator Janet Petro, whose ascension was a surprise. Her first act was to tell agency employees to remove diversity, equity, inclusion, and accessibility contracts and to “report” on anyone who did not carry out this order. Soon, civil servants began receiving emails from the US Office of Personnel Management that some perceived as an effort to push them to resign.
Then there are the actions of SpaceX founder Elon Musk. Last week he sowed doubt by claiming NASA had “stranded” astronauts on the space station. (The astronauts are perfectly safe and have a ride home.) Perhaps more importantly, he owns the space agency’s most important contractor and, in recent weeks, has become deeply enmeshed in operating the US government through his Department of Government Efficiency. For some NASA employees, whether or not it is true, there is now an uncomfortable sense that they are working for Musk and to dole out contracts to SpaceX.
This concern was heightened late Friday when Petro announced that a longtime SpaceX employee named Michael Altenhofen had joined the agency “as a senior advisor to the NASA Administrator.” Altenhofen is an accomplished engineer who interned at NASA in 2005 but has spent the last 15 years at SpaceX, most recently as a leader of human spaceflight programs. He certainly brings expertise, but his hiring also raises concerns about SpaceX’s influence over NASA operations. Petro did not respond to a request for comment on Monday about potential conflicts of interest and the scope of Altenhofen’s involvement.
I spent this weekend talking and texting with NASA sources at various centers around the country, and the overriding message is that morale at the agency is “absurdly low.” Meetings between civil servants and their leadership, such as an all-hands gathering at NASA’s Langley Research Center in Virginia recently, have been fraught with tension. No one knows what will happen next.
Racing has always been used to improve the breed, but now mostly with software.
Credit: Aurich Lawson | Getty Images | NASA
Credit: Aurich Lawson | Getty Images | NASA
DAYTONA BEACH—Last week, ahead of the annual Rolex 24 at Daytona and the start of the North American road racing season, IMSA (the sport’s organizers) held a tech symposium across the road from the vast speedway at Embry-Riddle University. Last year, panelists, including Crowdstrike’s CSO, explained the draw of racing to their employers; this time, organizations represented included NASA, Michelin, AMD, and Microsoft. And while they were all there to talk about racing, it seems everyone was also there to talk about simulation and AI.
I’ve long maintained that endurance racing, where grids of prototypes and road car-based racers compete over long durations—24 hours, for example—is the most relevant form of motorsport, the one that makes road cars better. Formula 1 has budgets and an audience to dwarf all others, and there’s no doubt about the level of talent and commitment required to triumph in that arena. The Indy 500 might have more history. And rallying looks like the hardest challenge for both humans and machines.
But your car owes its disc brakes to endurance racing, plus its dual-clutch transmission, if it’s one of the increasing number of cars fitted with such. But let’s not overblow it. Over the years, budgets have had to be reined in for the health of the sport. That—plus a desire for parity among the teams so that no one clever idea runs away with the series—means there are plenty of spec or controlled components on a current endurance racer. Direct technology transfer, then, happens less and less often—at least in terms of new mechanical bits or bobs you might find inside your next car.
Software has become a new competitive advantage for the teams that race hybrid sports prototypes from Acura, BMW, Cadillac, Porsche, and Lamborghini, just as it is between teams in Formula E.
But this year’s symposium shone a light on a different area of tech transfer, where Microsoft or NASA can use the vast streams of data that pour out of a 60-car, 24-hour race to build more accurate simulations and AI tools—maybe even ones that will babysit a crewed mission to Mars.
Sorry, did you say Mars?
“Critically, it takes light 20 minutes to make that trip, which has some really unfortunate operational impacts,” said Ian Maddox of NASA’s Marshall Space Flight Center’s Habitation office. A 40-minute delay between asking a question and getting an answer wouldn’t work for a team trying to win the Rolex 24, and “it certainly isn’t going to work for us,” he said.
“And so we’re placed in—I’ll be frank—the really uncomfortable position of having to figure out how to build AI tools to help the crew on board a Mars ship diagnose and respond to their own problems. So to be their own crew, to be their own engineering teams, at least for the subset of problems that can get really bad in the course of 45 minutes to an hour,” Maddox said.
Building those kinds of tools will require a “giant bucket of really good data,” Maddox said, “and that’s why we’ve come to IMSA.”
Individually, the hybrid prototypes and GT cars in an IMSA race are obviously far less complicated than a Mars-bound spacecraft. But when you get that data from all the cars in the race together, the size starts to become comparable.
“And fundamentally, you guys have things that roll and we have things that rotate, and you have things that get hot and cold, and so do we,” Maddox said. “When you get down to the actual measurement level, there are a lot of similarities between the stuff that you guys use to understand vehicle performance and the stuff we use to understand vehicle performance.”
Not just Mars
Other speakers pointed to areas of technology development—like tire development—that you may have read about recently here on Ars Technica. “[A tire is] a composite material made with more than 200 components with very non-linear behavior. It’s pressure-sensitive, it’s temperature-sensitive. It changes with wear… and actually, the ground interaction is also one of the worst mechanisms to try to anticipate and to understand,” said Phillippe Tramond, head of research of motorsport at Michelin.
For the past four years, Michelin has been crunching data gathered from cars racing on its rubber (and the other 199 components). “And eventually, we are able to build and develop a thermomechanical tire model able to mimic and simulate tire behavior, tire performance, whatever the specification is,” Tramond said.
That tool has been quite valuable to the teams racing in the GTP class of hybrid prototypes, as it means that their driver-in-the-loop simulators are now even more faithful to real life. But Michelin has also started using the tire model when developing road tires for specific cars with individual OEMs.
For Sid Siddhartha, a principal researcher at Microsoft Research, the data is again the draw. Siddhartha has been using AI to study human behavior, including in the game Rocket League. “We were able to actually show that we can really understand and home in on individual human behavior in a very granular way, to the point where if I just observe you for two or three seconds, or if I look at some of your games, I can tell you who played it,” Siddhartha said.
That led to a new approach by the Alpine F1 team, which wanted to use Siddhartha’s AI to improve its simulation tools. F1 teams will run entirely virtual simulations on upgraded cars long before they fire those changes up in the big simulator and let their human drivers have a go (as described above). In Alpine’s case, they wanted something more realistic than a lap time simulator that just assumed perfect behavior.
The dreaded BoP
“Eventually, we are connected to IMSA, and IMSA is interested in a whole host of questions that are very interesting to us at Microsoft Research,” Siddhartha said. “They’re interested in what are the limits of driver and car? How do you balance that performance across different classes? How do you anticipate what might happen when people make different strategic decisions during the race? And how do you communicate all of this to a fan base, which has really blown me away, as John was saying, who are interested in following the sport and understanding what’s going on.”
“Sports car racing is inherently complex,” said Matt Kurdock, IMSA’s managing director of engineering. “We’ve got four different classes. We have, in each car, four different drivers. And IMSA’s challenge is to extract from this race data that’s being collected and figure out how to get an appropriate balance so that manufacturers stay engaged in the sport,” Kurdock said.
IMSA has the cars put through wind tunnels and runs CFD simulations on them as well. “We then plug all this information into one of Michelin’s tools, which is their canopy vehicle dynamic simulation, which runs in the cloud, and from this, we start generating a picture of where we believe the optimized performance of each platform is,” Kurdock said.
Jonathan is the Automotive Editor at Ars Technica. He has a BSc and PhD in Pharmacology. In 2014 he decided to indulge his lifelong passion for the car by leaving the National Human Genome Research Institute and launching Ars Technica’s automotive coverage. He lives in Washington, DC.
NASA’s acting administrator is moving swiftly to remove diversity, equity, inclusion, and accessibility—or DEIA—programs from the space agency.
In an email sent to agency employees on Wednesday afternoon, acting administrator Janet Petro wrote, “We are taking steps to close all agency DEIA offices and end all DEIA-related contracts in accordance with President Trump’s executive orders titled Ending Radical and Wasteful Government DEI Programs and Preferencing and Initial Rescissions of Harmful Executive Orders and Actions.”
During his run for a second term as president, Trump campaigned on ending programs in the federal government that promote diversity, equity, and inclusion. He signed executive orders to that effect shortly after his inauguration on Monday.
Programs seen as divisive
These programs had their roots in affirmative action but exploded in popularity half a decade ago amid Trump’s first presidency and the #MeToo and Black Lives Matter movements. DEI programs and officers became commonplace in academia and major US corporations. However, even before the election of Trump, the DEI movement appeared to have crested. For example, last year the Massachusetts Institute of Technology ended the use of diversity statements for faculty hiring.
In explaining NASA’s position, Petro said of the agency’s existing DEIA activities, “These programs divided Americans by race, wasted taxpayer dollars, and resulted in shameful discrimination.”
Petro’s email is notable for its suggestion that some civil servants at NASA may have sought to shroud DEIA programs from the Trump administration since the presidential election in early November.
“We are aware of efforts by some in government to disguise these programs by using coded or imprecise language,” she wrote. “If you are aware of a change in any contract description or personnel position description since November 5, 2024 to obscure the connection between the contract and DEIA or similar ideologies, please report all facts and circumstances.”
This launch debuted a more advanced, slightly taller version of Starship, known as Version 2 or Block 2, with larger propellant tanks, a new avionics system, and redesigned feed lines flowing methane and liquid oxygen propellants to the ship’s six Raptor engines. SpaceX officials did not say whether any of these changes might have caused the problem on Thursday’s launch.
SpaceX officials have repeatedly and carefully set expectations for each Starship test flight. They routinely refer to the rocket as experimental, and the primary focus of the rocket’s early demo missions is to gather data on the performance of the vehicle. What works, and what doesn’t work?
Still, the outcome of Thursday’s test flight is a clear disappointment for SpaceX. This was the seventh test flight of SpaceX’s enormous rocket and the first time Starship failed to complete its launch sequence since the second flight in November 2023. Until now, SpaceX has made steady progress, and each Starship flight has achieved more milestones than the one before.
On the first flight in April 2023, the rocket lost control a little more than two minutes after liftoff, and the ground-shaking power of the booster’s 33 engines shattered the concrete foundation beneath the launch pad. Seven months later, on Flight 2, the rocket made it eight minutes before failing. On that mission, Starship failed at roughly the same point of its ascent, just before the cutoff of the vehicle’s six methane-fueled Raptor engines.
Back then, a handful of photos and images from the Florida Keys and Puerto Rico showed debris in the sky after Starship activated its self-destruct mechanism due to an onboard fire caused by a dump of liquid oxygen propellant. But that flight occurred in the morning, with bright sunlight along the ship’s flight path.
This time, the ship disintegrated and reentered the atmosphere at dusk, with impeccable lighting conditions accentuating the debris cloud’s appearance. These twilight conditions likely contributed to the plethora of videos posted to social media on Thursday.
Starship and Super Heavy head downrange from SpaceX’s launch site near Brownsville, Texas. Credit: SpaceX
The third Starship test flight last March saw the spacecraft reach its planned trajectory and fly halfway around the world before succumbing to the scorching heat of atmospheric reentry. In June, the fourth test flight ended with controlled splashdowns of the rocket’s Super Heavy booster in the Gulf of Mexico and of Starship in the Indian Ocean.
In October, SpaceX caught the Super Heavy booster with mechanical arms at the launch pad for the first time, proving out the company’s audacious approach to recovering and reusing the rocket. On this fifth test flight, SpaceX modified the ship’s heat shield to better handle the hot temperatures of reentry, and the vehicle again made it to an on-target splashdown in the Indian Ocean.
Most recently, Flight 6 on November 19 demonstrated the ship’s ability to reignite its Raptor engines in space for the first time and again concluded with a bullseye splashdown. But SpaceX aborted an attempt to again catch the booster back at Starbase due to a problem with sensors on the launch pad’s tower.
With Flight 7, SpaceX hoped to test more changes to the heat shield protecting Starship from reentry temperatures up to 2,600° Fahrenheit (1,430° Celsius). Musk has identified the heat shield as one of the most difficult challenges still facing the program. In order for SpaceX to reach its ambition for the ship to become rapidly reusable, with minimal or no refurbishment between flights, the heat shield must be resilient and durable.
The seventh test flight of Starship is scheduled for launch Thursday afternoon.
SpaceX’s upgraded Starship rocket stands on its launch pad at Starbase, Texas. Credit: SpaceX
SpaceX plans to launch the seventh full-scale test flight of its massive Super Heavy booster and Starship rocket Thursday afternoon. It’s the first of what might be a dozen or more demonstration flights this year as SpaceX tries new things with the most powerful rocket ever built.
There are many things on SpaceX’s Starship to-do list in 2025. They include debuting an upgraded, larger Starship, known as Version 2 or Block 2, on the test flight preparing to launch Thursday. The one-hour launch window opens at 5 pm EST (4 pm CST; 22: 00 UTC) at SpaceX’s launch base in South Texas. You can watch SpaceX’s live webcast of the flight here.
SpaceX will again attempt to catch the rocket’s Super Heavy booster—more than 20 stories tall and wider than a jumbo jet—back at the launch pad using mechanical arms, or “chopsticks,” mounted to the launch tower. Read more about the Starship Block 2 upgrades in our story from last week.
You might think of next week’s Starship test flight as an apéritif before the entrées to come. Ars recently spoke with Lisa Watson-Morgan, the NASA engineer overseeing the agency’s contract with SpaceX to develop a modified version of Starship to land astronauts on the Moon. NASA has contracts with SpaceX worth more than $4 billion to develop and fly two Starship human landing missions under the umbrella of the agency’s Artemis program to return humans to the Moon.
We are publishing the entire interview with Watson-Morgan below, but first, let’s assess what SpaceX might accomplish with Starship this year.
There are many things to watch for on this test flight, including the deployment of 10 satellite simulators to test the ship’s payload accommodations and the performance of a beefed-up heat shield as the vehicle blazes through the atmosphere for reentry and splashdown in the Indian Ocean.
If this all works, SpaceX may try to launch a ship into low-Earth orbit on the eighth flight, expected to launch in the next couple of months. All of the Starship test flights to date have intentionally flown on suborbital trajectories, bringing the ship back toward reentry over the sea northwest of Australia after traveling halfway around the world.
Then, there’s an even bigger version of Starship called Block 3 that could begin flying before the end of the year. This version of the ship is the one that SpaceX will use to start experimenting with in-orbit refueling, according to Watson-Morgan.
In order to test refueling, two Starships will dock together in orbit, allowing one vehicle to transfer super-cold methane and liquid oxygen into the other. Nothing like this on this scale has ever been attempted before. Future Starship missions to the Moon and Mars may require 10 or more tanker missions to gas up in low-Earth orbit. All of these missions will use different versions of the same basic Starship design: a human-rated lunar lander, a propellant depot, and a refueling tanker.
Artist’s illustration of Starship on the surface of the Moon. Credit: SpaceX
Questions for 2025
Catching Starship back at its launch tower and demonstrating orbital propellant transfer are the two most significant milestones on SpaceX’s roadmap for 2025.
SpaceX officials have said they aim to fly as many as 25 Starship missions this year, allowing engineers to more rapidly iterate on the vehicle’s design. SpaceX is constructing a second launch pad at its Starbase facility near Brownsville, Texas, to help speed up the launch cadence.
Can SpaceX achieve this flight rate in 2025? Will faster Starship manufacturing and reusability help the company fly more often? Will SpaceX fly its first ship-to-ship propellant transfer demonstration this year? When will Starship begin launching large batches of new-generation Starlink Internet satellites?
Licensing delays at the Federal Aviation Administration have been a thorn in SpaceX’s side for the last couple of years. Will those go away under the incoming administration of President-elect Donald Trump, who counts SpaceX founder Elon Musk as a key adviser?
And will SpaceX gain a larger role in NASA’s Artemis lunar program? The Artemis program’s architecture is sure to be reviewed by the Trump administration and the nominee for the agency’s next administrator, billionaire businessman and astronaut Jared Isaacman.
The very expensive Space Launch System rocket, developed by NASA with Boeing and other traditional aerospace contractors, might be canceled. NASA currently envisions the SLS rocket and Orion spacecraft as the transportation system to ferry astronauts between Earth and the vicinity of the Moon, where crews would meet up with a landing vehicle provided by commercial partners SpaceX and Blue Origin.
Watson-Morgan didn’t have answers to all of these questions. Many of them are well outside of her purview as Human Landing System program manager, so Ars didn’t ask. Instead, Ars discussed technical and schedule concerns with her during the half-hour interview. Here is one part of the discussion, lightly edited for clarity.
Ars: What do you hope to see from Flight 7 of Starship?
Lisa Watson-Morgan: One of the exciting parts of working with SpaceX are these test flights. They have a really fast turnaround, where they put in different lessons learned. I think you saw many of the flight objectives that they discussed from Flight 6, which was a great success. I think they mentioned different thermal testing experiments that they put on the ship in order to understand the different heating, the different loads on certain areas of the system. All that was really good with each one of those, in addition to how they configure the tiles. Then, from that, there’ll be additional tests that they will put on Flight 7, so you kind of get this iterative improvement and learning that we’ll get to see in Flight 7. So Flight 7 is the first Version 2 of their ship set. When I say that, I mean the ship, the booster, all the systems associated with it. So, from that, it’s really more just understanding how the system, how the flaps, how all of that interacts and works as they’re coming back in. Hopefully we’ll get to see some catches, that’s always exciting.
Ars: How did the in-space Raptor engine relight go on Flight 6 (on November 19)?
Lisa Watson-Morgan: Beautifully. And that’s something that’s really important to us because when we’re sitting on the Moon… well, actually, the whole path to the Moon as we are getting ready to land on the Moon, we’ll perform a series of maneuvers, and the Raptors will have an environment that is very, very cold. To that, it’s going to be important that they’re able to relight for landing purposes. So that was a great first step towards that. In addition, after we land, clearly the Raptors will be off, and it will get very cold, and they will have to relight in a cold environment (to get off the Moon). So that’s why that step was critical for the Human Landing System and NASA’s return to the Moon.
A recent artist’s illustration of two Starships docked together in low-Earth orbit. Credit: SpaceX
Ars: Which version of the ship is required for the propellant transfer demonstration, and what new features are on that version to enable this test?
Lisa Watson-Morgan: We’re looking forward to the Version 3, which is what’s coming up later on, sometime in ’25, in the near term, because that’s what we need for propellant transfer and the cryo fluid work that is also important to us… There are different systems in the V3 set that will help us with cryo fluid management. Obviously, with those, we have to have the couplers and the quick-disconnects in order for the two systems to have the right guidance, navigation, trajectory, all the control systems needed to hold their station-keeping in order to dock with each other, and then perform the fluid transfer. So all the fluid lines and all that’s associated with that, those systems, which we have seen in tests and held pieces of when we’ve been working with them at their site, we’ll get to see those actually in action on orbit.
Ars: Have there been any ground tests of these systems, whether it’s fluid couplers or docking systems? Can you talk about some of the ground tests that have gone into this development?
Lisa Watson-Morgan: Oh, absolutely. We’ve been working with them on ground tests for this past year. We’ve seen the ground testing and reviewed the data. Our team works with them on what we deem necessary for the various milestones. While the milestone contains proprietary (information), we work closely with them to ensure that it’s going to meet the intent, safety-wise as well as technically, of what we’re going to need to see. So they’ve done that.
Even more exciting, they have recently shipped some of their docking systems to the Johnson Space Center for testing with the Orion Lockheed Martin docking system, and that’s for Artemis III. Clearly, that’s how we’re going to receive the crew. So those are some exciting tests that we’ve been doing this past year as well that’s not just focused on, say, the booster and the ship. There are a lot of crew systems that are being developed now. We’re in work with them on how we’re going to effectuate the crew manual control requirements that we have, so it’s been a great balance to see what the crew needs, given the size of the ship. That’s been a great set of work. We have crew office hours where the crew travels to Hawthorne [SpaceX headquarters in California] and works one-on-one with the different responsible engineers in the different technical disciplines to make sure that they understand not just little words on the paper from a requirement, but actually what this means, and then how systems can be operated.
Ars: For the docking system, Orion uses the NASA Docking System, and SpaceX brings its own design to bear on Starship?
Lisa Watson-Morgan: This is something that I think the Human Landing System has done exceptionally well. When we wrote our high-level set of requirements, we also wrote it with a bigger picture in mind—looked into the overall standards of how things are typically done, and we just said it has to be compliant with it. So it’s a docking standard compliance, and SpaceX clearly meets that. They certainly do have the Dragon heritage, of course, with the International Space Station. So, because of that, we have high confidence that they’re all going to work very well. Still, it’s important to go ahead and perform the ground testing and get as much of that out of the way as we can.
Lisa Watson-Morgan, NASA’s HLS program manager, is based at Marshall Space Flight Center in Huntsville, Alabama. Credit: ASA/Aubrey Gemignani
Ars: How far along is the development and design of the layout of the crew compartment at the top of Starship? Is it far along, or is it still in the conceptual phase? What can you say about that?
Lisa Watson-Morgan: It’s much further along there. We’ve had our environmental control and life support systems, whether it’s carbon dioxide monitoring fans to make sure the air is circulating properly. We’ve been in a lot of work with SpaceX on the temperature. It’s… a large area (for the crew). The seats, making sure that the crew seats and the loads on that are appropriate. For all of that work, as the analysis work has been performed, the NASA team is reviewing it. They had a mock-up, actually, of some of their life support systems even as far back as eight-plus months ago. So there’s been a lot of progress on that.
Ars: Is SpaceX planning to use a touchscreen design for crew displays and controls, like they do with the Dragon spacecraft?
Lisa Watson-Morgan: We’re in talks about that, about what would be the best approach for the crew for the dynamic environment of landing.
Ars: I can imagine it is a pretty dynamic environment with those Raptor engines firing. It’s almost like a launch in reverse.
Lisa Watson-Morgan: Right. Those are some of the topics that get discussed in the crew office hours. That’s why it’s good to have the crew interacting directly, in addition to the different discipline leads, whether it’s structural, mechanical, propulsion, to have all those folks talking guidance and having control to say, “OK, well, when the system does this, here’s the mode we expect to see. Here’s the impact on the crew. And is this condition, or is the option space that we have on the table, appropriate for the next step, with respect to the displays.”
Ars: One of the big things SpaceX needs to prove out before going to the Moon with Starship is in-orbit propellant transfer. When do you see the ship-to-ship demonstration occurring?
Lisa Watson-Morgan: I see it occurring in ’25.
Ars: Anything more specific about the schedule for that?
Lisa Watson-Morgan: That’d be a question for SpaceX because they do have a number of flights that they’re performing commercially, for their maturity. We get the benefit of that. It’s actually a great partnership. I’ll tell you, it’s really good working with them on this, but they’d have to answer that question. I do foresee it happening in ’25.
Ars: What things do you need to see SpaceX accomplish before they’re ready for the refueling demo? I’m thinking of things like the second launch tower, potentially. Do they need to demonstrate a ship catch or anything like that before going for orbital refueling?
Lisa Watson-Morgan: I would say none of that’s required. You just kind of get down to, what are the basics? What are the basics that you need? So you need to be able to launch rapidly off the same pad, even. They’ve shown they can launch and catch within a matter of minutes. So that is good confidence there. The catching is part of their reuse strategy, which is more of their commercial approach, and not a NASA requirement. NASA reaps the benefit of it by good pricing as a result of their commercial model, but it is not a requirement that we have. So they could theoretically use the same pad to perform the propellant transfer and the long-duration flight, because all it requires is two launches, really, within a specified time period to where the two systems can meet in a planned trajectory or orbit to do the propellant transfer. So they could launch the first one, and then within a week or two or three, depending on what the concept of operations was that we thought we could achieve at that time, and then have the propellant transfer demo occur that way. So you don’t necessarily need two pads, but you do need more thermal characterization of the ship. I would say that is one of the areas (we need to see data on), and that is one of the reasons, I think, why they’re working so diligently on that.
Ars: You mentioned the long-duration flight demonstration. What does that entail?
Lisa Watson-Morgan: The simple objectives are to launch two different tankers or Starships. The Starship will eventually be a crewed system. Clearly, the ones that we’re talking about for the propellant transfer are not. It’s just to have the booster and Starship system launch, and within a few weeks, have another one launch, and have them rendezvous. They need to be able to find each other with their sensors. They need to be able to come close, very, very close, and they need to be able to dock together, connect, do the quick connect, and make sure they are able, then, to flow propellant and LOX (liquid oxygen) to another system. Then, we need to be able to measure the quantity of how much has gone over. And from that, then they need to safely undock and dispose.
Ars: So the long-duration flight demonstration is just part of what SpaceX needs to do in order to be ready for the propellant transfer demonstration?
Lisa Watson-Morgan: We call it long duration just because it’s not a 45-minute or an hour flight. Long duration, obviously, that’s a relative statement, but it’s a system that can stay up long enough to be able to find another Starship and perform those maneuvers and flow of fuel and LOX.
Ars: How much propellant will you transfer with this demonstration, and do you think you’ll get all the data you need in one demonstration, or will SpaceX need to try this several times?
Lisa Watson-Morgan: That’s something you can ask SpaceX (about how much propellant will be transferred). Clearly, I know, but there’s some sensitivity there. You’ve seen our requirements in our initial solicitation. We have thresholds and goals, meaning we want you to at least do this, but more is better, and that’s typically how we work almost everything. Working with commercial industry in these fixed-price contracts has worked exceptionally well, because when you have providers that are also wanting to explore commercially or trying to make a commercial system, they are interested in pushing more than what we would typically ask for, and so often we get that for an incredibly fair price.
Stephen Clark is a space reporter at Ars Technica, covering private space companies and the world’s space agencies. Stephen writes about the nexus of technology, science, policy, and business on and off the planet.
Julianna Scheiman, director of NASA science missions for SpaceX, said it made sense to pair the Firefly and ispace missions on the same Falcon 9 rocket.
“When we have two missions that can each go to the Moon on the same launch, that is something that we obviously want to take advantage of,” Scheiman said. “So when we found a solution for the Firefly and ispace missions to fly together on the same Falcon 9, it was a no-brainer to put them together.”
SpaceX stacked the two landers, one on top of the other, inside the Falcon 9’s payload fairing. Firefly’s lander, the larger of the two spacecraft, rode on top of the stack and deployed from the rocket first. The Resilience lander from ispace launched in the lower position, cocooned inside a specially designed canister. Once Firefly’s lander separated from the Falcon 9, the rocket jettisoned the canister, performed a brief engine firing to maneuver into a slightly different orbit, then released ispace’s lander.
This dual launch arrangement resulted in a lower launch price for Firefly and ispace, according to Scheiman.
“At SpaceX, we are really interested in and invested in lowering the cost of launch for everybody,” she said. “So that’s something we’re really proud of.”
The Resilience lunar lander is pictured at ispace’s facility in Japan last year. The company’s small Tenacious rover is visible on the upper left part of the spacecraft. credit: ispace Credit: ispace
The Blue Ghost and Resilience landers will take different paths toward the Moon.
Firefly’s Blue Ghost will spend about 25 days in Earth orbit, then four days in transit to the Moon. After Blue Ghost enters lunar orbit, Firefly’s ground team will verify the readiness of the lander’s propulsion and navigation systems and execute several thruster burns to set up for landing.
Blue Ghost’s final descent to the Moon is tentatively scheduled for March 2. The target landing site is in Mare Crisium, an ancient 350-mile-wide (560-kilometer) impact basin in the northeast part of the near side of the Moon.
After touchdown, Blue Ghost will operate for about 14 days (one entire lunar day). The instruments aboard Firefly’s lander include a subsurface drill, an X-ray imager, and an experimental electrodynamic dust shield to test methods of repelling troublesome lunar dust from accumulating on sensitive spacecraft components.
The Resilience lander from ispace will take four to five months to reach the Moon. It carries several intriguing tech demo experiments, including a water electrolyzer provided by a Japanese company named Takasago Thermal Engineering. This demonstration will test equipment that future lunar missions could use to convert the Moon’s water ice resources into electricity and rocket fuel.
The lander will also deploy a “micro-rover” named Tenacious, developed by an ispace subsidiary in Luxembourg. The Tenacious rover will attempt to scoop up lunar soil and capture high-definition imagery of the Moon.
Ron Garan, CEO of ispace’s US-based subsidiary, told Ars that this mission is “pivotal” for the company.
“We were not fully successful on our first mission,” Garan said in an interview. “It was an amazing accomplishment, even though we didn’t have a soft landing… Although the hardware worked flawlessly, exactly as it was supposed to, we did have some lessons learned in the software department. The fixes to prevent what happened on the first mission from happening on the second mission were fairly straightforward, so that boosts our confidence.”
The ispace subsidiary led by Garan, a former NASA astronaut, is based in Colorado. While the Resilience lander launched Wednesday is not part of the CLPS program, the company will build an upgraded lander for a future CLPS mission for NASA, led by Draper Laboratory.
“I think the fact that we have two lunar landers on the same rocket for the first time in history is pretty substantial,” Garan said. I think we all are rooting for each other.”
Investors need to see more successes with commercial lunar landers to fully realize the market’s potential, Garan said.
“That market, right now, is very nascent. It’s very, very immature. And one of the reasons for that is that it’s very difficult for companies that are contemplating making investments on equipment, experiments, etc., to put on the lunar surface and lunar orbit,” Garan said. “It’s very difficult to make those investments, especially if they’re long-term investments, because there really hasn’t been a proof of concept yet.”
“So every time we have a success, that makes it more likely that these companies that will serve as the foundation of a commercial lunar market movement will be able to make those investments,” Garan said. “Conversely, every time we have a failure, the opposite happens.”
