These scientists live like astronauts without leaving Earth

This article was originally published on Undark. Read the original article.

In January 2023, Tara Sweeney’s plane landed on Thwaites Glacier, a 74,000-square-mile mass of frozen water in West Antarctica. She arrived with an international research team to study the glacier’s geology and ice fabric, and how its ice melt might contribute to sea level rise. But while near Earth’s southernmost point, Sweeney kept thinking about the moon.

“It felt every bit of what I think it will feel like being a space explorer,” says Sweeney, a former Air Force officer who’s now working on a doctorate in lunar geology at the University of Texas at El Paso. “You have all of these resources, and you get to be the one to go out and do the exploring and do the science. And that was really spectacular.”

That similarity is why space scientists study the physiology and psychology of people living in Antarctic and other remote outposts: For around 25 years, people have played out what existence might be like on, or en route to, another world. Polar explorers are, in a way, analogous to astronauts who land on alien planets. And while Sweeney wasn’t technically on an “analog astronaut” mission—her primary objective being the geological exploration of Earth—her days played out much the same as a space explorer’s might.

For 16 days, Sweeney and her colleagues lived in tents on the ice, spending half their time trapped inside as storms blew snow against their tents. When the weather permitted, Sweeney snowmobiled to and from seismometer sites, once getting caught in a whiteout that, she says, felt like zooming inside a ping-pong ball.

On the glacier, Sweeney was always cold, sometimes bored, often frustrated. But she was also alive, elated. And she felt a form of focus that eluded her on her home continent. “I had three objectives: to be a good crewmate, to do good science, and to stay alive,” she says. “That’s all I had to do.”

None of that was easy, of course. But it may have been easier than landing back on the earth of El Paso. “My mission ended, and it’s over,” she says. “And how do I process through all these things that I’m feeling?”

Then, in May, she attended the 2023 Analog Astronaut Conference, a gathering of people who simulate long-term space travel from the relative safety and comfort of Earth. Sweeney had learned about the event when she visited an analog facility in the country of Jordan. There, she’d met one of the conference’s founders, Jas Purewal, who invited her to the gathering.

The meeting was held, appropriately, at Biosphere 2, a glass-paneled, self-contained habitat in the Arizona desert that resembles a 1980s sci-fi vision of a space settlement—one of the first facilities built, in part, to understand whether humans could create a habitable environment on a hostile planet.

wide view of the Biosphere 2 facilities
The 40-acre Biosphere 2 campus in Oracle, Arizona, was one of the first facilities built for analog astronaut missions.
UNIVERSITY OF ARIZONA

A speaker at the conference had spent eight months locked inside a simulated space habitat in Moscow, Russia, and she talked about how the post-mission period had been hard for her. The psychological toll of reintegration became a chattering theme throughout the whole meeting. Sweeney, it turned out, wasn’t alone.

Across the world, around 20 analog space facilities host people who volunteer to be study subjects, isolating themselves for weeks or months in polar stations, desert outposts, or even sealed habitats inside NASA centers. These places are intended to mimic how people might fare on Mars or the moon, or on long-term orbital stations. Such research, scientists say, can help test out medical and software tools, enhance indoor agriculture, and address the difficulties analog astronauts face, including, like Sweeney’s, those that come when their “missions” are over.

Lately, a community of researchers has started to make the field more formalized: laying out standards so that results are comparable; gathering research papers into a single database so investigators can build on previous work; and bringing scientists, participants, and facility directors together to share results and insights.

With that cohesion, a formerly quiet area of research is enhancing its reputation and looking to gain more credibility with space agencies. “I think the analogs are underestimated,” says Jenni Hesterman, a retired Air Force officer who is helping spearhead this formalization. “A lot of people think it’s just space camp.”


Analog astronaut facilities emerged as a way to test-drive space missions without the price tag of actually going to space. Scientists, for example, want to make sure tools work properly, and so analog astronauts will test out equipment ranging from spacesuits to extreme-environment medical equipment.

Researchers are also interested in how astronauts fare in isolation, and so they will sometimes track characteristics like microbiome changes, stress levels, and immune responses by taking samples of spit, skin, blood, urine, and fecal matter. Analog missions “can give us insights about how a person would react or what kind of team—what kind of mix of people—can react to some challenges,” says Francesco Pagnini, a psychology professor at the Catholic University of Sacred Heart in Italy, who has researched human behavior and performance in collaboration with the European and Italian space agencies.

Some facilities are run by space agencies, like NASA’s Human Exploration Research Analog, or HERA, which is located inside NASA’s Johnson Space Center in Houston. The center also houses a 3D-printed habitat called Crew Health and Performance Exploration Analog, or CHAPEA, where crews will simulate a year-long mission to Mars. The structure looks like what would happen if an artificial intelligence created a cosmic living space using IKEA as its source material.

“My mission ended, and it’s over,” Sweeney says. “And how do I process through all these things that I’m feeling?”

Most analog spots, though, are run by private organizations and take research proposals from space agencies, university researchers, and sometimes laypeople with projects that the facilities select through an application process.

Such work has been going on for decades: NASA’s first official analog mission took place in 1997, in Death Valley, when four people spent a week pretending to be Martian geologists. In 2000, the nonprofit Mars Society, a space-exploration advocacy and research organization, built the Flashline Mars Arctic Research Station in Nunavut, Canada, and soon after constructed the Mars Desert Research Station in Utah. (Both facilities have been used by NASA researchers, too.) But the practice was in place long before those projects, even if the terminology and permanent facilities were not: in the Apollo era, astronauts used to try out their rovers and space walks, along with scientific techniques, in Arizona and Hawaii.

Every day on “Mars,” Purewal and Hesterman’s team completed a set of missions, including simulated spacewalks.

Many facilities, according to Ronita Cromwell, formerly the lead scientist of NASA’s Flight Analogs Project, are located in two types of places: extreme environments or controlled ones. The former include Antarctic or Arctic research stations, which tend to be used to study topics like sleep patterns and team dynamics. The latter—sealed, simulated habitats—are primarily useful for human behavior research, like learning how cognitive ability changes over the course of a mission, or testing out equipment, like software that helps astronauts make decisions without communicating to mission control. That independence becomes necessary as crews travel farther from Earth, because the communication delays increase with distance.

During her work on NASA’s mission simulations, Cromwell saw their value. “What excited me is that we were able to create sort of spaceflight situations on the ground, to study spaceflight changes in the human body,” Cromwell says, “whether they be, you know, psychological, cognitive changes, or physiological changes.”

Psychiatry researchers from the University of Pennsylvania, for instance, recently found that members of a crew at HERA performed better on cognition tasks—like clicking on squares that randomly appear on a screen and memorizing three-dimensional objects—as their mission went on. Another recent HERA study, led by scientists at Northwestern and DePaul, found that over time, teams got better at executing physical tasks together, but worsened when they tried to work together creatively and intellectually on tasks like brainstorming as many uses as possible for a given object. Those brain and behavioral changes could teach scientists about tight teams deployed in other remote, tedious, stressful situations. “I think space psychology can also speak a lot about everyday life,” says Pagnini.

On the physical side, an international team that included a NASA scientist recently used the Mars Desert Research Station to test whether analog astronauts could be quickly taught how to fix broken bones using a device that could work on Mars—or an earthly site far from medical facilities. Investigations into self-contained, sustainable living reveal how low-resource existence could work on Earth, too. For example, another crew, led by Griffith University medical researchers, performed an experiment extracting water from minerals in case of emergency.

A view through the airlock, which connects the CHAPEA habitat to the sandbox area, where crew members will conduct simulated spacewalks.
NASA’s simulated Mars habitat includes a 1,200-square-foot sandbox with red sand to simulate the Martian landscape. The area will be used to conduct simulated spacewalks or “Marswalks” during the analog missions.

While scientific research that actually takes place in space usually gets the spotlight, the ground-testing of all systems, including human ones, is necessary, if not always glamorous or publicly lauded. “I felt like I was in charge of a deep, dark secret,” says Cromwell, jokingly, of her work on the NASA analog program.

In fact, even people who work in adjacent fields sometimes haven’t heard of the field. Purewal, an astrophysicist, only learned about analog space research in 2020. With covid-19 restrictions in place, though, most facilities had halted new missions. “If I can’t go to an analog, maybe I can bring the analog to me,” Purewal thought.

Amid the drapey willow branches and manicured hedges of her parents’ backyard in Warwick, England, she constructed a geodesic dome out of broomstick handles and tent-like materials. Purewal sequestered inside for a week, leaving only to use the bathroom—and then only while wearing a simulated spacesuit. She communicated with those outside her dome on a synthesized 20-minute delay and ate freeze-dried foods, which she came to hate, and insect protein from mealworms and locusts, which she came to like more than she anticipated.

While Purewal admits her personal analog was “low-fidelity,” it offered a test drive for more rigorous research. By 2021, Purewal had, with SpaceX civilian astronaut Sian Proctor, cofounded the Analog Astronaut Conference that Sweeney attended, along with an associated online community of more than 1,000 people. She also participated in an analog mission in someone else’s backyard—one surrounded by Utah State Trust Lands—in November 2022. Their endeavor was sponsored by the Mars Society and involved research on mental health, geologic research tools, and sustainable food supplies, all of which would be necessary if they were going to Mars.


But they weren’t headed to Mars; they were headed to Utah. About five minutes from the small town of Hanksville—home to “Hollow Mountain,” a gas station convenience store dug out of a rock formation—sits the turnoff to the Mars Desert Research Station. Operated by the Mars Society, the facility is 3.4 miles down a dirt track called N Cow Dung Road. The landscape looks otherworldly: mushroom-shaped rock formations; sandy, granular ground; and eroded hills of red rock.

A view into two living quarters with beds
The 1,700-square-foot CHAPEA habitat contains individual living quarters for four volunteer crew members.
BILL STAFFORD/NASA

The station sits in a flat spot surrounded by those hills, with a cylindrical living space two stories tall but just 26 feet in diameter. The habitat links out via above-ground “tunnels” to a greenhouse and a geodesic dome that resembles Purewal’s initial backyard creation, and houses a control center and lab.

In November 2022, Purewal brought a team there for two weeks, with Hesterman as commander. In the habitat, an astrobiology student tried to grow edible mushrooms in the crew’s food waste. Another team member wanted to see if they could make yogurt from powdered milk and bacteria. Purewal, meanwhile, was experimenting with an AI companion robot called PARO. Shaped like a baby harp seal, PARO is typically used to relieve stress in medical situations. The crew members interacted with PARO and wore bio-monitoring straps that measured things like heart rate as they did so.

After their mission ended, they spoke with others, and heard about issues such as expired fire extinguishers, or the lack of safety training for participants who would be using specialized technologies and life support systems. They consulted Emily Apollonio, a former aircraft accident investigator. In 2022, she traveled to Hawaii to live at HI-SEAS, a 1,200-square-foot analog station located 8,200 feet above sea level on the Mauna Loa volcano. Apollonio thought HI-SEAS had avoidable problems. For one, the bathroom had only a composting toilet, which the mission crew weren’t allowed to pee in, and a urinal, which the women had to use too.

With a draft version released this June, they hope to improve conditions for participants—ensuring, for instance, that facilities adhere to building codes and provide adequate medical support. They also want to encourage analog participants to follow research best practices to ensure rigorous outputs. The standards suggest, for instance, that each mission have its research plan pre-validated by the principal investigator and habitat director, a timeline for research completion, and an Institutional Review Board approval in place for human experiments. While projects with federal or institutional grant funding go through these steps anyway, the formality isn’t uniform across the board.

The 2011 version of the deep space habitat at the Desert Research and Technology Studies (Desert RATS) analog field test. This configuration includes the Habitat Demonstration Unit with the student-built X-Hab loft on top, a hygiene compartment on one side, and an airlock on the other.
NASA

While some analogs already have rigorous protocols in place to protect participants, the safety issues and inclusivity gaps she heard about from colleagues helped inspire Apollonio to start a training and consulting company called Interstellar Performance Labs to help prepare would-be analog astronauts before their missions. She also started to work with Purewal, Hesterman, and others on a document called “International Guidelines and Standards for Space Analogs.”

The standards also detail the creation of a research database, putting all the write-ups (peer-reviewed and otherwise) of analog projects in one place. That way, people aren’t duplicating efforts—as the mushroom grower, it turns out, was—unless they mean to test the replicability of results. They can also better link their studies to space agencies’ established needs to be more directly helpful and relevant to the real world.

“I didn’t know where to look, I didn’t know where to go,” Apollonio says. “I couldn’t hear my thoughts.”

As part of this centralization effort, Purewal, Apollonio, Hesterman, and colleagues are also putting together what they call the World’s Biggest Analog: a simultaneous, month-long mission involving at least 10 isolated bases across the world, which together will simulate a large, cooperative future presence in space.

So far, though, attempts to give the community cohesion and coherency have yet to fully address the aspect of analog life that gives many participants trouble: the end of their mission. “Being in an analog mission was less difficult than coming out an analog mission,” says Apollonio, of her own experience.

Shortly after emerging from HI-SEAS, she walked around the streets of Waikiki with her husband. The lights, the noise—everything was too much. “I didn’t know where to look, I didn’t know where to go,” she says. “I couldn’t hear my thoughts.” After they chose a restaurant for dinner, and the server handed her a menu, she froze. “I have to choose my own food,” she realized. It was overwhelming, and that feeling didn’t abate.

Meanwhile, few other people understood the experience, says Hesterman. “You come home and you’re all excited, like, you want to tell everybody about it,” she continues. “You tell everybody about it once, and then they’re just done. On back to paying the bills and cutting the grass and stuff. You still want to talk about it.”

Purewal missed the team and the sense of shared purpose, and started to seek it outside the simulation. “I need to find this same feeling in my day-to-day life,” she says. “We all kind of need our crew.”


Research on the post-mission experience is scant, says Pagnini. In March 2023, he coauthored a review paper, commissioned by the European Space Agency, which aimed to lay out the state of research on human behavior and performance in space, including gaps in the science. Studying how astronauts react and cope “post-mission,” his research found, has been particularly neglected. The same is true of returning from analog space.

Pagnini says the research isn’t just relevant to analog or actual astronauts. Life in space has similarities to life on Earth—including in its difficulties. Italy’s heavily restrictive and prolonged covid-19 lockdown, for instance, resembled going away on a mission. “When we got out of the lockdown phase, getting in touch with other people was kind of strange,” he says. Much of living a regular life on Earth was strange.

Analog astronauts stand with their hand together
An analog crew returns after their 45-day simulated mission at NASA’s Human Exploration Research Analog, or HERA.
NASA

The strangeness also characterizes other experiences, like military deployments and the subsequent return to domestic life. “The expectation is kind of that families will live happily ever after” once they’re reunited, says Leanne Knobloch, a professor of communication at the University of Illinois, who performed a large reintegration study on military couples. “So that’s why reintegration has sometimes been overlooked, but more and more researchers are starting to recognize that it is a challenging period, and it’s not the storybook ending that people make it out to be.”

Analog missions give crew members a chance to practice skills like opening a rover.
THE MARS SOCIETY

Knobloch’s work includes suggestions for easing the transition, such as preparing people for the issues they’re likely to experience. “If you’re ready and expect that you might experience some of these problems, it won’t be so stressful,” she says. “Because you’ll recognize that they’re normal.”

Apollonio’s Interstellar Performance Labs, for one, is already planning to include education on “aftercare,” educating people about what she calls the “deorbiting effect” of returning to regular life.


When the day finally came for Sweeney to depart Thwaites Glacier, the aircraft seemed to materialize right out of the sky, as though the remote outpost had transformed into a busy airport. As she was leaving, she looked down at the camp where half her team remained. “You could just see how small our little footprint was,” she says. A speck in the middle of endless white space.

Since she landed in North America, Sweeney has savored time with her family. But the adjustment hasn’t been easy. “Each day that ticks by of being back, I started feeling pulled in different directions,” she says. With numerous projects ongoing—mentoring, speaking, doing her doctoral research—she felt her sense of self splintering. In Antarctica, she had been a smooth, singular whole.

But at the Analog Astronaut Conference in May, hearing about others’ similar readjustment difficulties, Sweeney felt some sense of normalcy. Having a community of support could help with post-mission struggles. Further research—aided by the new database and standardization measures—could help uncover best coping strategies, along with the keys to successful crew dynamics, stress creators and mitigators, and tools and designs that make the practicalities of a mission easier. Maybe someone will look at the database, see this scientific gap, and try to fill it.

Such research might resonate with Sweeney and others having trouble readjusting to their daily lives. “We have to get back to work, we have to go see our families, we want to pick up the projects we were doing before,” she says. “But also, we need to make space for the magnitude of the experience that we just had. And to be able to decompress from that.”

Future space food could be made from astronaut breath

The future of space food could be as simple—and weird—as a protein shake made with astronaut breath or a burger made from fungus.

For decades, astronauts have relied mostly on pre-packaged food, or the occasional grown lettuce, during their forays off our planet. With missions beyond Earth orbit in sight, a NASA-led competition is hoping to change all that and usher in a new era of sustainable space food.

“Currently the pre-packaged food that we use on the International Space Station has a shelf life of a year and a half,” says Ralph Fritsche, senior project manager for space crop production at NASA’s Kennedy Space Center in Florida. “We don’t have a food system at this point in time that can really handle a mission to Mars,” he says. Longer-duration missions to the moon would present a similar problem. 

And while it may be some time before humans ever reach Mars, the moon is very much on the agenda. Next year, NASA plans to send four astronauts flying around the moon as part of its Artemis program, in the first crewed moon mission since Apollo 17 in 1972. The goal is to get humans back on the surface later this decade, at first for days at a time but eventually for weeks, months, or even longer.

To solve the problem of feeding astronauts on long-duration missions, NASA started the Deep Space Food Challenge in January 2021, asking companies to propose novel ways to develop sustainable foods for future missions. About 200 companies entered—a field that was whittled down to 11 teams in January 2023 as part of phase 2, with eight US teams each given $20,000 in funding and three additional international teams also recognized. On May 19, NASA is set to announce the teams that will progress into the final phase of the contest, with a handful of winners to be announced in April 2024 following more detailed tests of their proposals.

“Phase 2 was kind of a kitchen-level demonstration,” says Angela Herblet at NASA’s Marshall Space Flight Center in Alabama, the project manager for the challenge. “Phase 3 is going to challenge the teams to scale their technologies.”

Entrants had to show systems that could operate for three years and feed a crew of four on a prospective space mission. The proposals did not need to supply a crew’s entire diet, but they did need to create a variety of nutritious foods for the astronauts. Earlier this year, judges then visited each company to “see the food and really analyze it,” says Herblet.

One company took a particularly unusual approach to the task. Air Company, based in New York and one of the eight US-based finalists, designed a system that could use the carbon dioxide expelled by astronauts in space to produce alcohol, which could then be used to grow edible food. The company already develops alcohols from CO2 for plane fuel and perfume.

“It’s making food out of air,” says Stafford Sheehan, cofounder and chief technology officer of Air Company. “It sounds like magic, but when you see it actually operating, it’s much more simple. We’re taking CO2, combining it with water and electricity, and making proteins.”

The founders of Air Company, Dr Stafford Sheehan and Gregory Constantine.
Air Company, founded by Stafford Sheehan and Gregory Constantine, is exploring transforming carbon dioxide into fuel for yeast.
AIR COMPANY

The process produces alcohol that can then be fed to yeast, producing “something that’s edible,” says Sheehan. For the competition they created essentially a protein shake, described as being similar to one made from seitan, a vegan meat substitute. “It actually tastes pretty good,” says Sheehan. For astronauts in space, the system would ferment continuously to supply food. “Whenever you feel like you want a space protein shake, you make one from this yeast that’s growing,” says Sheehan.

Interstellar Lab in Florida, another of the US-based phase 2 finalists, had a different approach. Its system, called NUCLEUS, is a modular set of small toaster-size capsules. Each is self-contained, with its own humidity, temperature, and watering system. That would allow different vegetables—or even insects such as black soldier flies, often cited as a promising protein source—to be cultivated so that astronauts can easily grow their own food in space.

“We’re bringing a little bit of the Earth ecosystem into space,” says Barbara Belvisi, the company’s founder and CEO. “You can grow mushrooms, insects, and microgreens at the same time.”

a worker opens one Nucleus unit in a stack from a stack of nine.
looking out from within the interior of a Nucleus unit where a worker is tending to a plant.

Interstellar Lab’s stackable NUCLEUS capsules are designed to be tended by astronauts and monitored by software.

the interior of the BioPod where rows of green edible plants are lit by artificial grow lamps
Interstellar Lab’s BioPod is designed to require no outside water source.
INTERSTELLAR LAB

Astronauts would need to spend three to four hours per week seeding, pruning, and cultivating the crops, but for the most part it would be AI-controlled. “NASA didn’t want to get rid of full human intervention,” says Belvisi. “It was still needed to give some occupation to the astronauts.” The company has also designed larger inflatable self-contained environments, called BioPods, that it hopes could one day be used on the moon or Mars.

One of the three international finalists is Mycorena, based in Sweden. Its system, AFCiS, produces a type of protein called mycoprotein from the fermentation of fungus to replace animal- or plant-based sources. “It has a very high protein content, up to 60%,” says Kristina Karlsson, the company’s head of research and development. It is also rich in fiber, vitamins, and nutrients, while low in fats and sugars.

two scientists making mycoprotein
a pile of promyc protein

Mycorena’s AFCiS system (left) produces a nutrient-rich mycoprotein that could also be formed into 3D printed shapes.

By itself, the mycoprotein doesn’t taste of much, Karlsson says: “It’s very neutral, like umami or yeasty bread.” But further processing, including combining it with flavorings or spices, could yield a wide range of foods, such as burgers or nuggets. A module attached to the system 3D-prints the fungus into the desired food style. “You can pick from a screen and eat a chicken filet,” says Karlsson.

While the winning ideas from the Deep Space Food Challenge won’t immediately be incorporated into future planned landings on the moon’s surface, they will show what might be possible on future missions. “You’ve got to start years in advance to make sure you have the capability in place when you need it,” says Fritsche. Those capabilities look promising—just don’t forget that side of soldier flies with your 3D-printed space fungus.

Amazon is about to go head to head with SpaceX in a battle for satellite internet dominance 

Elon Musk and Jeff Bezos are about to lock horns once again. Last month, the US Federal Communications Commission approved the final aspects of Project Kuiper, Amazon’s effort to deliver high-speed internet access from space. In May, the company will launch test versions of the Kuiper communications satellites in an attempt to take on SpaceX’s own venture, Starlink, and tap into a market of perhaps hundreds of millions of prospective internet users.

Other companies are hoping to do the same, and a few are already doing so, but Starlink and Amazon are the major players. “It is really a head-to-head rivalry,” says Tim Farrar, a satellite expert from the firm TMF Associates in the US. 

The rocket that will launch Amazon’s first two Kuiper satellites—the United Launch Alliance’s new Vulcan Centaur rocket—has been assembled at Cape Canaveral in Florida. Its inaugural launch is set to fly two prototype Kuiper satellites, called KuiperSat-1 and KuiperSat-2, as early as May 4. Ultimately, Amazon plans to launch a total of 3,236 full Kuiper satellites by 2029. The first of that fleet could launch in early 2024.

“They have ambitions to be disruptive across the technology sector,” says Farrar. “It’s hardly surprising that they’ve jumped in here.”

In the past few years, companies have been trying to expand access to the internet via satellite, both as commercial ventures and to supply internet to those in remote locations without otherwise easy access. Starlink, the mega-constellation of more than 3,500 satellites built by Musk’s SpaceX, is the biggest of these ventures. 

Amazon announced Project Kuiper in 2019, the same year Starlink began launching, leading Musk to tweet that Bezos, then the company’s CEO, was a “copycat.” Others are in development too, such as the UK-based OneWeb, which currently has more than 500 satellites. But Farrar says the key competition is between SpaceX and Amazon.

To take on SpaceX, last year Amazon revealed it had essentially bought all the spare rocket launch capacity in the world (although with little effect on its rival, because SpaceX launches satellites on its own rockets). Thanks to Amazon’s multibillion-dollar deals with United Launch Alliance, Bezos’s Blue Origin in the US, and Arianespace in Europe, Project Kuiper satellites are expected to fly on 92 different launches over the next five years.

The rapid launch cadence is important. Under its license with the FCC, Amazon has until July 2026 to launch half its constellation. “We are on track to meet that deadline,” an Amazon spokesperson said. Last month, the FCC gave Amazon the full green light to begin launching its satellites after the company finalized details of its plan to address concerns about its potential to increase space junk.

But there is a catch: none of the rockets Amazon has bought a ride on has yet made it to space (in fact, one launch vehicle Amazon had initially planned to use exploded in January). “Those rockets are largely behind schedule,” says Farrar.

The satellites are meant to orbit at an altitude of about 600 kilometers and cover latitudes from Canada to Argentina, reaching “95% of the world’s population,” the Amazon spokesperson said. “Our constellation will serve individual households, as well as businesses, schools, hospitals, government agencies, and other organizations operating in locations without reliable broadband.” 

Amazon has applied to the FCC to increase its constellation to 7,774 satellites, which would allow it to cover regions further north and south, including Alaska, as Starlink does.

There are riches to be had: SpaceX currently charges $110 a month to access Starlink, with an up-front cost of $599 for an antenna to connect to the satellites. According to a letter to shareholders last year, Amazon is spending “over $10 billion” to develop Kuiper, with more than 1,000 employees working on the project. Andy Jassy, Amazon’s current CEO, has said that Kuiper has a chance of becoming a “fourth pillar” for the company, alongside its retail marketplace, Amazon Prime, and its widely used cloud computing service, Amazon Web Services

“Amazon’s business model relies on people having internet connectivity,” says Shagun Sachdeva, an industry expert at the space investment firm Kosmic Apple in France. “It makes a lot of sense for them to have this constellation to provide connectivity.”

Amazon is not yet disclosing the pricing of its service but has previously said a goal is to “bridge the digital divide” by bringing fast and affordable broadband to “underserved communities,” an ambition Starlink has also professed. But whether costs will ever get low enough for that to be achievable remains to be seen. “Costs will come down, but to what extent is really the question,”  says Sachdeva. On March 14, the company revealed it was producing its own antennas at a cost of $400 for a standard antenna, although a retail cost has not yet been revealed.

Amazon has said it can offer speeds of up to one gigabit per second, and bandwidth of one terabit per second. Those are similar to Starlink’s numbers, and the two services seem fairly similar overall. The key difference is that Starlink is operational, and has been for years, whereas Amazon does not plan to start offering Kuiper as a service until the latter half of 2024, giving SpaceX a considerable head start to attract users and secure contracts.

The astronomy problem

There remain concerns, too, about space junk and the impact on ground-based astronomy. Before 2019 there were only about 3,000 active satellites in space. SpaceX and Amazon by themselves could increase that number to 20,000 by the end of this decade. Tracking large numbers of moving objects in orbit—and making sure they don’t collide with one another—is a headache.

“I’m not satisfied that we can safely sustain [even] one of these systems in orbit,” says Hugh Lewis, a space debris expert at the University of Southampton in the UK, who has tracked thousands of close calls between Starlink, OneWeb, and other satellites. “They’re continually rolling the dice. At some point, in spite of all their best efforts, I think there will be a collision.”

Amazon’s spokesperson said the company had “designed our system and operational parameters with space safety in mind.” When satellites finish their mission, the spokesperson added, they will be removed from orbit within one year using onboard thrusters, and in the case of satellite failure, atmospheric drag will “help ensure any remaining satellites will deorbit naturally.”

Amazon has not revealed the size of its satellites, but—like Starlink’s—they might reflect enough sunlight to pose a problem to astronomers and even change the appearance of the night sky. Attempts to lessen the impact satellites have on astronomy have been moderately successful at best, with the satellites appearing particularly bright at twilight. Telescope observations of the universe are already affected by bright satellite streaks, and the problem is likely to worsen in the future.  

Amazon has said it is working with astronomers on the issue. “Reflectivity is a key consideration in our design and development process,” the company spokesperson said. “We’ve already made a number of design and operational decisions that will help reduce our impact on astronomical observations.”

If the problem cannot fully be solved, however, some aspects of astronomy will become much more difficult or even impossible. “Starlink has not managed to make their satellites nearly as faint as they promised,” says Samantha Lawler, an astronomer at the University of Regina in Canada. “I’m quite worried what the sky will look like with yet another company launching thousands of potentially bright satellites.”

With plans to build up to four satellites per day, Amazon plans to progress rapidly. After its first two test satellites have launched, the rest could come thick and fast. Can the company take on Musk? “That’s the big question,” says Farrar. “They have to move quickly.”

This story was updated on 23 March to clarify the figure of $400 is the cost to build a standard Kuiper antenna and to correct a typo regarding Project Kuiper’s bandwidth.

How the James Webb Space Telescope broke the universe

The James Webb Space Telescope is one of MIT Technology Review’s 10 Breakthrough Technologies of 2023. Explore the rest of the list here.

Natalie Batalha was itching for data from the James Webb Space Telescope. It was a few months after the telescope had reached its final orbit, and her group at the University of California, Santa Cruz, had been granted time to observe a handful of exoplanets—planets that orbit around stars other than our sun.

Among the targets was WASP-39b, a scorching world that orbits a star some 700 light-years from Earth. The planet was discovered years ago. But in mid-July, when Batalha and her team got their hands on the first JWST observations of the distant world, they saw a clear signature of a gas that is common on Earth but had never been spotted before in the atmosphere of an exoplanet: carbon dioxide. On Earth, carbon dioxide is a key indicator of plant and animal life. WASP-39b, which takes just four Earth days to orbit its star, is too hot to be considered habitable. But the discovery could well herald more exciting detections—from more temperate worlds—in the future. And it came just a few days into the lifetime of JWST. “That was a very exciting moment,” says Batalha, whose group had gathered to glimpse the data for the first time. “The minute we looked, the carbon dioxide feature was just beautifully drawn out.”

This was no accident. JWST, a NASA-led collaboration between the US, Canada, and Europe, is the most powerful space telescope in history and can view objects 100 times fainter than what the Hubble Space Telescope can see. Almost immediately after it started full operations in July of 2022, incredible vistas from across the universe poured down, from images of remote galaxies at the dawn of time to amazing landscapes of nebulae, the dust-filled birthplaces of stars. “It’s just as powerful as we had hoped, if not more so,” says Gabriel Brammer, an astronomer at the University of Copenhagen in Denmark.

But the speed at which JWST has made discoveries is due to more than its intrinsic capabilities. Astronomers prepared for years for the observations it would make, developing algorithms that can rapidly turn its data into usable information. Much of the data is open access, allowing the astronomical community to comb through it almost as fast as it comes in. Its operators have also built on lessons learned from the telescope’s predecessor, Hubble, packing its observational schedule as much as possible.

For some, the sheer volume of extraordinary data has been a surprise. “It was more than we expected,” says Heidi Hammel, a NASA interdisciplinary scientist for JWST and vice president for science at the Association of Universities for Research in Astronomy in Washington, DC. “Once we went into operational mode, it was just nonstop. Every hour we were looking at a galaxy or an exoplanet or star formation. It was like a firehose.”

Now, months later, JWST continues to send down reams of data to astonished astronomers on Earth, and it is expected to transform our understanding of the distant universe, exoplanets, planet formation, galactic structure, and much more. Not all have enjoyed the flurry of activity, which at times has reflected an emphasis on speed over the scientific process, but there’s no doubt that JWST is enchanting audiences across the globe at a tremendous pace. The floodgates have opened—and they’re not shutting anytime soon.

Opening the pipe

JWST orbits the sun around a stable point 1.5 million kilometers from Earth. Its giant gold-coated primary mirror, which is as tall as a giraffe, is protected from the sun’s glare by a tennis-court-size sunshield, allowing unprecedented views of the universe in infrared light.

The telescope was a long time coming. First conceived in the 1980s, it was once planned for launch around 2007 at a cost of $1 billion. But its complexity caused extensive delays, devouring money until at one point it was dubbed “the telescope that ate astronomy.” When JWST finally launched, in December 2021, its estimated cost had ballooned to nearly $10 billion

Even post-launch, there have been anxious moments. The telescope’s journey to its target location beyond the moon’s orbit took a month, and hundreds of moving parts were required to deploy its various components, including its enormous sunshield, which is needed to keep the infrared-­sensitive instruments cool.

The aim is to keep the telescope as busy as possible: “The worst thing we could do is have an idle telescope.”

But by now, the delays, the budget overruns, and most of the tensions have been overcome. JWST is hard at work, its activities carefully choreographed by the Space Telescope Science Institute (STScI) in Baltimore. Every week, a team plans out the telescope’s upcoming observations, pulling from a long-term schedule of hundreds of approved programs to be run in its first year of science, from July 2022 to June 2023.

The aim is to keep the telescope as busy as possible. “The worst thing we could do is have an idle telescope,” says Dave Adler at STScI, the head of long-range planning for JWST. “It’s not a cheap thing.” In the 1990s, Hubble would occasionally find itself twiddling its thumbs in space if programs were altered or canceled; JWST’s schedule is deliberately oversubscribed to prevent such issues. Onboard thrusters and reaction wheels, which spin to change the orientation, move the telescope with precision between various targets across the sky. “The goal is always to minimize the amount of time we’re not doing science,” says Adler.

The result of this packed schedule is that every day, JWST can collect more than 50 gigabytes of data, compared with just one or two gigabytes for Hubble. The data, which contains images and spectroscopic signatures (essentially light broken apart into its elements), is fed through an algorithm run by STScI. Known as a “pipeline,” it turns the telescope’s raw images and numbers into useful information. Some of this is released immediately on public servers, where it is picked up by eager scientists or even by Twitter bots such as the JWST Photo Bot. Other data is handed to scientists on programs that have proprietary windows, enabling them to take time analyzing their own data before it is released to the masses.

The galaxies of Stephan’s Quintet, in an image created with data from two of JWST’s infrared instruments. The leftmost galaxy appears to be part of the group but sits much closer to Earth.
NASA, ESA, CSA, STSCI

Pipelines are essentially pieces of code, made with programming languages like Python. They have long been used in astronomy but advanced considerably in 2004  after astronomers used Hubble to spend 1 million seconds observing an empty patch of sky. The goal was to look for remote galaxies in the distant universe, but 800 exposures would be taken, so Hubble’s planners knew it would be too daunting a task to do by hand.

Instead, they developed a pipeline to turn the exposures into a usable image, a taxing technical challenge given that each image required its own calibration and alignment. “There was no way you could expect the community at that time to combine 800 exposures on their own,” says Anton Koekemoer, a research astronomer at STScI. “The goal was to enable science to be done much more quickly.” The incredible image resulting from those efforts revealed 10,000 galaxies stretching across the universe, in what came to be known as the Hubble Ultra Deep Field. 

With JWST, a single master pipeline developed by STScI takes images and data from all its instruments and makes them science-ready. Many astronomers, both amateur and professional, then use their own pipelines developed in the months and years before launch to further investigate the data. That’s why when JWST’s data began streaming down to Earth, astronomers were able to almost immediately understand what they were seeing, turning what would normally be months of analysis time into just hours of processing time.

“We were sitting there ready,” says Brammer. “All of a sudden, the pipe was open. We were ready to go.”

Galaxies everywhere 

Orbiting just a few hundred miles above Earth’s surface, the Hubble Space Telescope is close enough for astronauts to visit. And over the years, they did, undertaking a series of missions to repair and upgrade the telescope, starting with a trip to fix its infamously misshapen mirror—a problem discovered shortly after launch in 1990. JWST, which sits farther away than the moon, is on its own.   

Lee Feinberg, JWST’s optical telescope element manager at NASA’s Goddard Space Flight Center, was among those waiting to see whether the telescope would actually deliver. “We spent 20 years simulating the alignment of the telescope,” he says—that is, making sure that it could accurately point at targets across the sky. 

By March, the wait was over. JWST had reached its target location beyond the moon, and Feinberg and his colleagues were finally ready to start taking test images. As he walked into STScI one morning, one of those images, a test image of a star, was put up on screen. It contained an amazing surprise. “There were literally hundreds of galaxies,” says Feinberg. “We were just blown away.” So detailed was the image that it revealed galaxies stretching away into the distant universe, even though it hadn’t been taken for such a purpose. “Everybody was in disbelief how well it was working,” he says.

Following a further process of testing and calibrating instruments to get the telescope up and running, one of JWST’s earliest tasks was to look at WASP-39b with its cryogenically cooled Mid-Infrared Instrument (MIRI). This tool is the one aboard the telescope that observes most deeply in the infrared part of the spectrum, where many of the signatures of planetary atmospheres can be readily detected. MIRI’s spectrograph allowed scientists to pick apart the light from WASP-39b’s atmosphere. Rather than analyzing the observations manually, however, the team used a pipeline called Eureka!, developed by Taylor Bell, an astronomer at the Bay Area Environmental Research Institute at NASA’s Ames Research Center in California. “The objective was to go from the raw data that comes down to information about the atmospheric spectrum,” says Bell. Analyzing information from an exoplanet like this would usually require months of work. But within hours of the observations, the signature of carbon dioxide leaped out. A host of other details have since been released about the planet, including a detailed analysis of its composition and the presence of patchy clouds.

Others have used pipelines for much more distant targets. In July, studying early images from JWST, a team led by Rohan Naidu at MIT discovered GLASS-z13, a remote galaxy whose light could date from just 300 million years after the Big Bang—earlier than any galaxy known before. The discovery caused a global furor because it suggested that galaxies may have formed earlier than previously expected, perhaps by a few hundred million years—meaning our universe took shape faster than previously believed. 

Naidu’s discovery was made possible by EAZY, a pipeline Brammer developed to somewhat crudely analyze the light of galaxies in JWST images. “It estimates the distance of the objects using these imaging observations,” says Brammer, who posted the tool on the software website GitHub for anybody to use. 

Rush hour

Traditionally in science, researchers will submit a scientific paper to a journal, where it is then reviewed by peers in the field and finally approved for publication or rejected. This process can take months, even years, sometimes delaying publication—but always with accuracy and scientific rigor in mind.

There are ways to bypass this process, however. A popular method is to post early versions of scientific papers on the website arXiv prior to peer review. This means that research can be read or publicized before it is published in a journal. In some cases, the research is never submitted to a journal, instead remaining solely on arXiv and discussed openly by scientists on Twitter and other forums.

Posting on arXiv is popular when there is a new discovery that scientists are keen to publish quickly, sometimes before competing papers come out. In the case of JWST, about a fifth of its first-year programs are open access, meaning the data is immediately released publicly when it is transferred down to Earth. That puts the research team that proposed the program in immediate competition with others watching the data stream in. When the telescope’s firehose of data was switched on in July, many researchers turned to arXiv to publish early results—for better or worse.

“When you’re dealing with something this new and this unknown, things should be checked 10 or 100 times. That’s not how things went.”

Emiliano Merlin

“There was a rush to publish anything as soon as possible,” says Emiliano Merlin, an astronomer at the Astronomical Observatory of Rome who was involved in early JWST analysis efforts such as the race to find galaxies in the distant universe after the Big Bang. The discovery of GLASS-z13 and a dozen or so other intriguing candidates was published before follow-up observations could confirm the age of their light. “It was not something I personally really liked,” says Merlin. “When you’re dealing with something this new and this unknown, things should be checked 10 or 100 times. That’s not how things went.”

One concern was that early calibration issues with the telescope could have resulted in errors. But so far many of the early results have stood up to scrutiny. Follow-up observations have confirmed GLASS-z13 to be a record-breaking early galaxy, although its age has been slightly reduced, leading to a renaming of the galaxy to GLASS-z12. The possible discovery of other galaxies that formed even earlier than GLASS-z12 suggests that our understanding of how structure emerged in the universe may very likely need to be rethought, perhaps even hinting at more radical models for the early universe.  

The Near-Infrared Camera aboard JWST captured this snapshot of Neptune in July. Researchers said it was the clearest view of the giant planet’s rings since the Voyager 2 flyby in 1989.
This image of a star was taken during testing of JWST’s optical alignment. But it incidentally showcased the sensitivity of the telescope, with a number of galaxies appearing in the background.

Ernie Wright stands near the JWST mirrors
Segments of JWST’s primary mirror are prepped for cryogenic testing in 2011. The full mirror, made of gold-coated beryllium, consists of 18 segments and spans 6.5 meters. It was designed to be folded up for launch.
NASA/MSFC/DAVID HIGGINBOTHAM

While many of JWST’s programs publicly release data immediately, sometimes resulting in a frantic rush to post results early, about 80% of them have a proprietary period, allowing the researchers running them exclusive access to their data for 12 months. This enables scientists, especially smaller groups that lack the resources of large institutions, to more carefully scrutinize their own data before releasing it to the public.

“Proprietary time evens out the lumps and bumps in resources,” says Mark McCaughrean, senior advisor for science and exploration at the European Space Agency and a JWST scientist. “If you take away proprietary periods, you stack it back in the direction of the big teams.”

Many scientists do not use their full 12-month allocation, however, which means they will only add to the constant stream of discoveries from JWST. Alongside the open-access observations being taken, there will be more and more proprietary results released to the public. “Now that the firehose is open, we will be seeing papers continuously for the next 10 years and beyond,” says Hammel. Perhaps well past that—Feinberg says the telescope may have more than 20 years of fuel, allowing operations to continue far into the 2040s.

“We’re cracking open an entirely new window on the universe,” says Hammel. “That’s just a really exciting moment to be a part of, for us as a species.” 

A version of this story appeared in the January/February 2023 issue of the magazine.

NASA’s return to the moon is off to a rocky start

It was December 14, 1972, the final day on the moon for the last Apollo mission. The Challenger lander was dusted in a fine coating of gray lunar dirt, called regolith, both inside and out. Geologist Jack Schmitt was packing the sample containers, securing 243 pounds of rocks to bring home. After passing Schmitt the last science instruments, commander Eugene Cernan took a final look at the landscape before climbing into the spacecraft behind him. 

“As we leave the moon,” Cernan radioed to Houston, “we leave as we came, and God willing as we return, with peace and hope for all mankind.” He ascended the ladder, leaving the last set of bootprints on the moon, on a valley between a range of low mountains and soft sculptured hills.

Five decades later, NASA has a plan to send astronauts back to the lunar surface. Called Artemis, after the sister of Apollo in Greek mythology, the project aims to visit a new area of the moon and retrieve new samples, this time with new faces behind the sun visors—including the first woman and first person of color. 

Whether this plan will succeed—and whether a fresh moon landing will inspire a new “Artemis generation” in space exploration, as NASA leadership hopes—is a matter of debate. The differences between Artemis and the Apollo program, which itself fizzled out sooner than many had hoped, are certainly stark. Artemis is built on a less exact, less nimble, and much less well-heeled vision of space exploration than the one that launched Cernan and his predecessors. Where Apollo was conceived and executed as a high-priced monument to American ingenuity and the power of capitalism, its sister program is more a reflection of American politics and the power of inertia.   

Though the program is officially only three years old, elements of Artemis have been in the works for many years, even decades. Its ancillary projects, spread throughout NASA and at university partners across the US, in many cases existed long before the Trump administration gave the program a name. Its origins were rocky even before fueling problems and two hurricanes delayed its first launch in November. 

Artemis has many disparate purposes, serving very different groups. For some space enthusiasts, it’s simply a way back to the moon, a destination that will always loom largest in our collective consciousness. For others, it represents a path to Mars. Some see Artemis as a way to reclaim American superiority in space, something that was most visibly lost when the space shuttle retired in 2011. Still others see it as a means to unlock a new era of scientific discovery and invention, first undertaken during Apollo but arguably begun the first time humans looked at the moon and wondered what it was. 

The project’s first mission, an uncrewed test flight called Artemis 1, thundered to space in the middle of the night on November 16. It was carried into space by the most powerful rocket ever launched, the Space Launch System (SLS). Towering 15 feet taller than the Statue of Liberty, the SLS consists of an orange main tank flanked by white boosters that make it resemble the space shuttle, its progenitor in both propulsion and programmatic style. After multiple missed deadlines and criticism from Congress, multiple White House occupants, and NASA’s own auditors, space exploration fans and scientists  were amped to go back to the moon. 

But overshadowing Artemis is the uncomfortable fact that the rocket, not the moon missions it will carry, has long been the primary goal of NASA’s human spaceflight program. Where exactly that rocket is going has always been secondary—and the destination has changed multiple times. If something goes wrong, or if SLS is deemed too expensive or unsustainable, there’s a chance the entire moon program will fail or at least be similarly judged. This is a wobbly, uncertain start to an effort to return humans to the lunar surface for the first time in a half-century—and could make that return, if it does happen, a very brief one. 


On February 1, 2003, the skies over Texas flashed with what appeared to be a daytime meteor shower. The bright objects were pieces of the space shuttle Columbia, which had broken apart during its 28th reentry through Earth’s atmosphere. As the nation mourned the shuttle’s seven crew members, President George W. Bush began work on a new way forward for NASA. 

Artemis has its roots in that effort. In January 2004, less than a year after the Columbia disaster, Bush announced a Vision for Space Exploration—a reimagining of the space program that called for retiring the shuttle by 2011, scuttling the International Space Station by 2016, and replacing them with a new program called Constellation. Constellation would consist of a new, configurable rocket capable of launching to the moon or even to Mars, named Ares; a new crew vehicle for low Earth orbit, called Orion; and a new lunar lander, named Altair.

But Constellation never coalesced into anything more than a collection of ideas. By the time Barack Obama became president in 2009, the program was already years behind schedule. Obama convened another commission, led by former Lockheed Martin CEO Norman Augustine, to study Constellation. The Augustine Committee judged the project too expensive and underfunded to ever succeed—a fatal combination that watchdogs said would jeopardize other NASA missions. The Obama administration zeroed out the funding for the project, effectively thwarting the nation’s moonward trajectory once again. 

“Everybody who was willing to talk to you about it acknowledged there wasn’t any money planned to go into the big rocket or the lunar lander until after the space station was retired,” recalls Lori Garver, who was deputy administrator at NASA when Constellation fell on the chopping block. “It was just a shell.” 

Shortly after the program got the ax, however, members of Congress insisted on funding the rocket anyway, eager to keep the jobs attached to the effort after the shuttle era ended. Though it was not part of the White House’s budget request, Congress holds the nation’s purse strings and had the power to hand out lucrative contracts to legacy companies like Lockheed and Boeing. 

Obama administration officials scrambled to find a place to send the rocket they were given. They decided on an asteroid. The rocket would be used to retrieve one with a robotic spacecraft, which would tug it closer to Earth for a human landing. “It got funded as a rocket to nowhere, and we at NASA had to figure out something to do with it,” Garver says. The rocket (which was rebranded as the Space Launch System) and the Asteroid Redirect Mission both chugged along separately for the next few years, though many scientists and engineers criticized the asteroid program. The rocket’s first uncrewed launch was initially scheduled for 2016. Launch dates continually slipped in the following six years. 

In the meantime, thanks in part to another program supported by President Obama, the space industry was blossoming. Elon Musk’s SpaceX developed its reusable Falcon 9 rocket (and later its own large rocket, the Falcon Heavy), launching military and civilian satellites for the government. In 2020, the company began carrying up astronauts, restarting the ability to send humans into space from US soil. Other private companies, including Jeff Bezos’s Blue Origin, started launching civilians, mainly celebrities and tourists, into space. Meanwhile, NASA engineers continued toiling with space shuttle technology. Legacy contractors like Boeing continued to receive large bonus payments for working on the SLS, despite delays and mushrooming costs—drawing criticism from congressional watchdog groups and NASA auditors. 

Shortly after Donald Trump took office in 2017, the much-maligned asteroid program was canceled. Trump’s team tried to cancel the rocket too, but the effort was blocked by powerful senators, especially Richard Shelby of Alabama, who chaired the Senate Appropriations Committee and was SLS’s chief champion (prompting some to call it the “Senate Launch System”). So the rocket remained—with no destination until 2019, when Trump’s NASA administrator, James Bridenstine, announced Artemis, a series of missions to orbit the moon, land on its surface, and begin building a permanent settlement. The first crewed mission is scheduled to loop around the moon in 2024, and the first Artemis landing is currently scheduled for 2025.


The scientific and cultural payoff for a lunar return could be huge. Scientists have many lingering questions about the moon’s formation, and Earth’s early history, that may be answerable with fresh samples from the lunar far side. Researchers are already preparing a flotilla of instruments and robotic experiments to fly on Artemis-adjacent private landers, funded through the Commercial Lunar Payload Services program, which may pave the way for a return to the moon that distributes risk and reward between NASA and private industry. 

NASA’s public-facing descriptions of Artemis talk about “going forward” to the moon, not going back. Much of the rhetoric around the moon return includes an eventual trip to Mars as well. Agency officials often say that going back to the moon will teach us how to live and work on another world, paving a path for eventual human exploration of the Red Planet. 

Among those preparing for the lunar return is Chris Dreyer, a mechanical engineering professor at the Colorado School of Mines. Dreyer is leading a NASA-funded project studying lunar construction. His team is designing an autonomous moon bulldozer, which would scoop and flatten regolith to prepare a construction site for a landing pad. Artemis landers, which will be built by SpaceX, will be heavier and taller than the spindly Apollo lunar modules, which is why they will need a landing pad; otherwise, the strength of their own exhaust would reshape the ground beneath them, blowing regolith about like the powdered sugar on a doughnut. A landing pad will ensure that landers won’t tip over as they set down. 

NASA’s Space Launch System (SLS) rocket, with the Orion spacecraft aboard, is seen at sunrise atop the mobile launcher.
NASA/JOEL KOWSKY

“If you look through all of Apollo, you realize every landing was a bit of an adventure in avoiding boulder fields. Everything was just at the limit of what was possible,” Dreyer says. “We could go back and do that again, but it wouldn’t advance anything. Part of Artemis is about advancing living and working in space, and I see this construction as part of that.”

Artemis will make those advances slowly. The rocket is scheduled to launch once every year and a half; critics argue that momentum and public support could wane with such long waits between launches. Previous exploration programs have faced dwindling interest over time.Apollo’s fast and furious pace ensured that the first landing happened within just eight years, but by the sixth Apollo landing, Americans had begun arguing for spending on domestic programs instead. By the 25th shuttle mission, NASA tried to inject new excitement by putting a teacher on board. Christa McAuliffe was killed along with six other crew members when the space shuttle Challenger was destroyed just over a minute after it launched in January 1986. 

Critics of the Space Launch System argue that the rocket is unsustainable by design, relying on an old and potentially quite expensive way to get to space. Much of SLS is a holdover from the space shuttle. NASA had 16 leftover shuttle main engines, 14-foot-long cones that were clustered in trefoil arrays on the bottom end of the shuttle orbiters. Those will be repurposed to power SLS. But while the shuttle orbiter, engines, and external tanks were designed to be reusable, SLS and its engines were not. The first Artemis flight used old shuttle engines; the next planned launches will use others. But after that, new engines will be needed. Aerojet Rocketdyne has a $1.79 billion contract to begin building more, starting with the as-yet-unplanned Artemis 5 mission.

“They’ve designed a rocket that is basically unsustainable, because it’s completely throwaway. The only bit that comes back is Orion,” says Clive Neal, a lunar geologist at Notre Dame and an outspoken critic of NASA’s moon plans. “I get incredibly frustrated.”

NASA argues that it is using the most-tested rocket engines in history, and that recycling them for the moon saves money. But not that much money, it turns out. In early 2022, NASA’s inspector general told Congress that the first three flights of the SLS would cost $4.1 billion apiece, a level he called “unsustainable.” NASA and Boeing later said the price tag would be lower, and outside analysts have said each launch would cost between $876 million and $2 billion, depending on how you break down overhead costs. 

“Depending on how you look at it, the SLS is either a product of a broken system that curries favor to wealthy industries or an example of representative democracy working as it should,” wrote Casey Dreier, chief advocate and senior space policy advisor at the Planetary Society, in a recent essay. 


There may be alternative ways to return humans to the moon. Several heavy-launch commercial rockets are in development. SpaceX is building a reusable vehicle called Starship, which includes a configuration that is aimed at taking astronauts all the way to the moon; Blue Origin has a reusable rocket called New Glenn; and even legacy rocket builders United Launch Alliance have a huge rocket called the Vulcan Centaur, which is slated to begin launching science instruments and privately funded landers to the moon early this year. Garver says she was surprised that NASA under President Joe Biden chose a version of Starship to take Artemis astronauts to the lunar surface: “It’s an acknowledgment that Starship is going to work. And if Starship is going to work, then you don’t need SLS and Orion.” 

Artemis has created jobs in every state and poured research money into dozens of universities. There’s a chance the program may survive in pieces even if the rocket doesn’t. Previous human space exploration programs were consolidated under one umbrella within NASA, but for Artemis, agency management under Trump instead established a more distributed method for funding different projects. While NASA’s inspector general criticized this approach, some observers believe it may make Artemis more sustainable in the long term, and better able to withstand shifting political winds. 

There is something indefinable and awe-inspiring about sending humans to another world. In some sense we share their experience; they are avatars for us all. 

As of now, the rocket is not Artemis’s only hurdle in a path toward long-term human habitation on the moon. Space travel is still difficult, even when you do it all the time. And going back to the moon is proving to be hard for NASA. Some observers believe a human landing in 2025 is wildly ambitious. 


If Artemis were solely about science, NASA would send robots, as it has done with missions to the sun and out to Mars, Jupiter, Saturn, and beyond the edge of the solar system. But the moon still beckons, and the call is for human visitors like Cernan, not just landers and rovers. China and the European Space Agency have set their sights on this achievement too. Robots just aren’t enough. “It is fundamentally changing what it means to be human, on some level,” says Teasel Muir-Harmony, the Apollo curator at the Smithsonian Air and Space Museum in Washington.

There is something indefinable and awe-inspiring about sending humans to another world. In some sense we share their experience; they are avatars for us all. That may be why, despite criticism of the rocket, it’s difficult to find anyone who will say something negative about Artemis. Returning to the moon is a human imperative for some people. “It is a desire written in the human heart,” as Bush said, memorializing the Columbia crew. The experience will never cease to be amazing, and for space exploration advocates, it will never cease to be a worthy goal. 

Artemis, like America itself, is an experiment begun years ago with good intentions. It was flawed from the outset, in part because of those good intentions and in part for more cynical reasons. It was bequeathed to hardworking people who genuinely want something good to come of it but are hamstrung by problems that predate them and may be too fundamental to ever fully fix, at least in the project’s current form. Yet it is all we have, for now. The rocket remains funded. The missions are scheduled. NASA says, “We are going.” And the moon will be waiting, indifferent to which vehicle we use to get there.

Rebecca Boyle is a science journalist based in Colorado Springs. Her first book, Walking With the Moon, is forthcoming from Random House in 2024.

What’s next in space in 2023

We’re going back to the moon—again—in 2023. Multiple uncrewed landings are planned for the next 12 months, spurred on by a renewed effort in the US to return humans to the lunar surface later this decade. Both private space companies and national agencies are set to make the 240,000-mile trek to our celestial neighbor, where they will test landing capabilities, look for usable water ice, and more.

Previous years were “all about Mars,” says Jill Stuart, a space policy expert from the London School of Economics in the UK. “Now we’ve shifted back to the moon.”

That is not all 2023 has in store. We’re also likely to see significant strides made in private human spaceflight, including the first-ever commercial spacewalk, compelling missions heading out into—or back from—other solar system destinations, and new rockets set to take flight.

Here’s what the next year has lined up for space.

Moon landings

A lunar lander will already be on its way when 2023 begins. Launched in December on a SpaceX Falcon 9 rocket, the private spacecraft Hakuto-R, developed by Japanese firm ispace, is on a four-month journey to reach the moon, where it will deploy rovers built by the space agencies of Japan and the United Arab Emirates, among other goals. If successful, Hakuto-R could become the first private mission to land on the moon in March.

We say “could” because two private landers from the US—one from the firm Astrobotic and the other from Intuitive Machines, called Peregrine and Nova-C, respectively—are also set to reach the moon around the same time. Both are NASA-backed missions with various instruments on board to study the lunar environment, part of the agency’s Commercial Lunar Payloads Services program, which aims to spur commercial interest in the moon ahead of human missions planned for later this decade under its Artemis program.

The first part of that program, Artemis I, saw an uncrewed Orion spacecraft launch to the moon on NASA’s giant new Space Launch System rocket in November 2022. While the next Artemis mission, a crewed flight around the moon, is not planned until 2024, these next 12 months will lay important groundwork for Artemis by studying the moon’s surface and even looking for water ice that could be a potential target for future human missions, among other goals. “The moon is getting a lot more attention than it has done for many years,” says Jon Cowart, a former NASA human spaceflight manager now at the Aerospace Corporation in the US.

Intuitive Machines has a second lunar landing planned in 2023. Also on the books are landings from the space agencies of India and Japan, with Chandrayaan-3 and SLIM (Smart Lander for Investigating Moon), respectively. India hopes to launch in August 2023. It will be the country’s second attempt—the first crash-landed on the moon in 2019. A date for SLIM, which will test precision landing on the moon, has not yet been set. Russia reportedly has plans for the moon in 2023 too with its Luna-25 lander, but the status of the mission is unclear.

Private space travel

Since May 2020, SpaceX has been using its Crew Dragon spacecraft to ferry astronauts to space, some to the International Space Station (ISS) under contract with NASA and others on private missions. But SpaceX’s Polaris Dawn mission, currently slated for March 2023, will be a big new step.

Four commercial astronauts, including billionaire Jared Isaacman, who is paying for the flight and also funded SpaceX’s first all-private human spaceflight in 2021, will target a maximum orbit of 1,200 kilometers, higher than any human spacecraft since the Apollo missions. And in a first for commercial human spaceflight, the crew will don spacesuits and venture outside the spacecraft.

“Polaris Dawn is really exciting,” says Laura Forczyk from the space consulting firm Astralytical. “My understanding is that the entire vehicle will be evacuated. Everybody is going to at least stick their heads out.”

The mission may help NASA decide whether a future Crew Dragon mission could be used to service the Hubble Space Telescope, a capability that the agency has been investigating with SpaceX. “We’ll have some idea whether it’s feasible,” says Forczyk.

Two more private missions using Crew Dragon—Axiom-2 and Axiom-3—are planned to head for the ISS in 2023, as well as two NASA flights using Crew Dragon. A competing vehicle from the US firm Boeing is also set to launch with crew for the first time in April 2023, following multiple delays.

Meanwhile, we wait to see if Jeff Bezos’s company Blue Origin will be allowed to launch with humans again. The company has been grounded following an uncrewed launch failure in September 2022. Another private spaceflight pioneer, Virgin Galactic, has been relatively quiet since it launched its founder Sir Richard Branson into space in July 2021. 

All these developments in commercial human spaceflight may be overshadowed by the first orbital flight attempt of SpaceX’s massive and reusable Starship rocket, which was undergoing launchpad tests earlier this month and should launch in 2023, if not by the end of 2022.

If successful, the rocket, which would surpass NASA’s Space Launch System as the largest rocket to make it to orbit, could transform our exploration of space. “The ability to take more mass up opens up new opportunities,” says Uma Bruegman, an expert in space strategies at the Aerospace Corporation. That could include, one day, human missions to Mars—or beyond. But there’s a long way to go yet. “It’s definitely an important year [for Starship],” says Cowart. “They’ve got a lot to do.” One of its nearer-term goals will be preparing for the moon—NASA chose Starship’s upper stage as the initial lunar lander for the Artemis program.

Into the solar system

Moons of the solar system’s biggest planet are also on the agenda next year. April 2023 will see a gripping new mission launch from the European Space Agency (ESA) called JUICE, for “Jupiter Icy Moons Explorer.” Scheduled to arrive in orbit at Jupiter in 2031, the spacecraft will perform detailed studies of the Jovian moons Ganymede, Callisto, and Europa, all of which are thought to harbor oceans that could contain life beneath their icy surfaces.

“It’s the first mission that’s fundamentally focused on the icy moons,” says Mark McCaughrean, senior advisor for science and exploration at ESA. “We now know these icy moons have very deep water oceans, and they could have the conditions for life to have developed.”

JUICE will map these oceans with radar instruments, but McCaughrean says it will also be able to look for possible biosignatures on the surface of Europa’s ice, which could rain down from plumes ejected into space from its subsurface ocean.

Later in 2023, ESA is scheduled to see another major mission launch: its Euclid telescope, which was switched from a Russian rocket to a SpaceX Falcon 9 rocket following Russia’s invasion of Ukraine. The telescope will probe the “dark universe,” observing billions of galaxies over a third of the sky to better understand dark matter and dark energy in the cosmos.

In October, NASA should launch a significant science mission of its own when Psyche takes flight following a delay from 2022. The spacecraft will head to 16 Psyche, an unusual metal-rich asteroid that has never been seen up close.

A number of other intriguing developments are expected in 2023. NASA’s OSIRIS-REx mission is scheduled to return to Earth in September with pieces of an asteroid called Bennu, which could offer new insight into the structure and formation of the solar system. Amazon aims to send up the first satellites for Project Kuiper in early 2023, the start of a 3,000-satellite orbiting communications network it hopes will rival SpaceX’s Starlink constellation. And several new rockets are set to launch, including the United Launch Alliance’s Vulcan Centaur rocket (it will carry Astrobotic’s moon lander and some of Amazon’s satellites) and possibly Blue Origin’s large New Glenn rocket. Both are heavy-lift rockets that could take many satellites into space.

“There’s a huge swathe of activity,” says Cowart. “I’m very excited about this year.”

This story is a part of MIT Technology Review’s What’s Next series, where we look across industries, trends, and technologies to let you know what to expect in the coming year.

Starlink signals can be reverse-engineered to work like GPS—whether SpaceX likes it or not

Todd Humphreys’s offer to SpaceX was simple. With a few software tweaks, its rapidly growing Starlink constellation could also offer ultra-precise position, navigation, and timing. The US Army, which funds Humphreys’s work at the University of Texas at Austin, wanted a backup to its venerable, and vulnerable, GPS system. Could Starlink fill that role?

When the idea was first proposed in 2020, executives at SpaceX were open to the idea, says Humphreys. Then word came from on high. “Elon told the leaders we spoke to: every other LEO [low Earth orbit] communications network has gone into bankruptcy,” Humphreys told MIT Technology Review. “And so we [SpaceX] have to focus completely on staying out of bankruptcy. We cannot afford any distractions.”

But Humphreys wouldn’t take no for an answer. For the past two years, his team at UT Austin’s Radionavigation Lab has been reverse-engineering signals sent from thousands of Starlink internet satellites in low Earth orbit to ground-based receivers. Now Humphreys says his team has cracked the problem, and he believes that regular beacon signals from the constellation, designed to help receivers connect with the satellites, could form the basis of a useful navigation system. Crucially, this could be done without any help from SpaceX at all. 

In a non peer-reviewed paper that he has posted on his lab’s website, Humphreys claims to have provided the most complete characterization of Starlink’s signals to date. This information, he says, is the first step toward developing a new global navigation technology that would operate independently of GPS or its European, Russian, and Chinese equivalents. 

“The Starlink system signal is a closely guarded secret,” says Humphreys. “Even in our early discussions, when SpaceX was being more cooperative, they didn’t reveal any of the signal structure to us. We had to start from scratch, building basically a little radio telescope to eavesdrop on their signals.”

To get the project started, UT Austin acquired a Starlink terminal and used it to stream high-definition tennis videos of Rafael Nadal from YouTube. This provided a constant source of Starlink signals that a separate nearby antenna could listen in on.

Humphreys quickly realized that Starlink relies on a technology called orthogonal frequency-division multiplexing (OFDM). OFDM is an efficient method of encoding digital transmissions, originally developed at Bell Labs in the 1960s and now used in Wi-Fi and 5G. “OFDM is all the rage,” says Mark Psiaki, a GPS expert and aerospace professor at Virginia Tech. “It’s a way to pack the most bits per second into a given bandwidth.” 

The UT Austin researchers did not try to break Starlink’s encryption or access any user data coming down from satellites. Instead, they sought out synchronization sequences—predictable, repeating signals beamed down by the satellites in orbit to help receivers coordinate with them. Not only did Humphreys find such sequences, but “we were pleasantly surprised to find that they [had] more synchronization sequences than is strictly required,” he says.

Each sequence also contains clues to the satellite’s distance and velocity. With the Starlink satellites transmitting about four sequences every millisecond “that’s just wonderful for dual use of their system for positioning,” says Humphreys. 

If the terrestrial receiver has a good idea of the satellites’ movements—which SpaceX shares online to reduce the risk of orbital collisions—it can use the sequences’ regularity to work out which satellite they came from, and then calculate the distance to that satellite. By repeating this process for multiple satellites, a receiver can locate itself to within about 30 meters, says Humphreys.

If SpaceX later decided to cooperate by including additional data on each satellite’s exact position in its downlinks, that accuracy could theoretically improve to less than a meter—making it competitive with GPS. SpaceX did not respond to requests for comment.

Other researchers have been treading a similar path. Zak Kassas is a professor in the department of Electrical and Computer Engineering at Ohio State University and the director of a US Department of Transportation center focusing on navigation resiliency. Last year, his team was the first to demonstrate that Starlink signals could be used for positioning, in part using machine learning. 

Kassas’s approach, which he calls cognitive opportunistic navigation, analyzes the period and changing frequencies of signals from a satellite as it travels overhead. The receiver also uses the synchronization sequences, learns the satellite’s orbit, and tracks it. With multiple satellite passes, the receiver ultimately calculates its own location. At a recent conference, Kassas claimed his system had now achieved accuracies of less than 10 meters with Starlink. “It’s a framework that is so general we can apply it to any terrestrial or extraterrestrial signal,” he says. “It will learn on the fly, tell you what is being transmitted, and tell you where you are.”

A fuller understanding of Starlink’s signals has implications beyond navigation. For instance, the Starlink satellites currently don’t seem to be using two of the eight channels that SpaceX is licensed for. Humphreys speculates that this could be because Musk is keen not to interfere with radio telescopes operating at neighboring frequencies. The bright streaks of orbiting Starlink satellites have already been accused of disrupting optical astronomy.

UT Austin’s findings also highlight the possibility of deliberate interference with Starlink itself. Humphreys notes that while the synchronization sequences hold promise for navigation, the fact that they are utterly predictable and are used across the whole constellation is a security vulnerability. “Humphreys has done a big service to the navigation community identifying these sequences,” says Psiaki. “But any navigation system working on open-source sequences could definitely be spoofed, because everyone will know how to spot those signals and create fake ones.”

Starlink reportedly suffered a catastrophic loss of communications in late September in Ukraine, where it is being widely used for voice and electronic communications, to help fly drones, and even to correct artillery fire. Although it is unclear whether the outages were due to jamming by Russian forces, Musk tweeted last week: “Russia is actively trying to kill Starlink. To safeguard, SpaceX has diverted massive resources towards defense.”

Starlink has unquestionably been a lifesaver for Ukraine. However, reports of the outages and continued confusion about who will be paying for Starlink services there raise concerns over its future. 

“As time goes on and their dependence on Starlink deepens, Ukraine and its allies in the West are coming to appreciate that they have little control over Starlink and know little about it,” says Humphreys. “But now many millions have a vested interest in Starlink security, including its resilience to jamming.  Assessing that security starts with a clear understanding of the signal structure.”