An illustration of the moon with text overlaid that reads

Credit: Gary Neill

A bigger, bolder moon shot

NASA's Artemis missions will return humans to Earth's satellite for the first time in 50 years. Why go back? A new era of deep space exploration beckons.

Andrew Driesman remembers July 20, 1969, like yesterday. Six years old, he watched the grainy images on his family's black-and-white TV as Neil Armstrong and Buzz Aldrin took the first human steps on the moon. The shadow-strewn celestial body looked so foreign and alien, Driesman says, and the astronauts' strange, bouncelike movements in low gravity played on an endless loop in his mind.

Now, more than five decades later, Driesman is gearing up for another moon landing, only this time he's not a passive bystander sitting cross-legged on the carpet. He's the mission area executive for Civil Space Flight at the Johns Hopkins University Applied Physics Laboratory, working at the forefront of the space sector to push forward NASA's ambitious moon return through its Artemis program.

For some, NASA's moon return can feel inconsequential, given that we touched down on our celestial neighbor during Apollo 11 and five other Apollo missions spanning 1969 to 1972. But Artemis differs significantly from the Cold War space race between the United States and the Soviet Union.

"With Apollo, we were there to beat the Russians, and once we beat the Russians, the program lost its steam," Driesman says. "This time around, the mission isn't a one-and-done race to a finish line. It's our step off the planet, a long-term bet on building a sustainable presence beyond Earth."

Artemis involves a bold undertaking: build a lunar science and industrial basecamp on the far side of the moon and later use the basecamp as a launchpad for exploring Mars—and establishing human colonies beyond Earth in our solar system. The plan sounds far-fetched, as though torn from the pages of an H.G. Wells novel. But it's fast becoming a reality. In 2022, NASA launched its first Artemis mission, an uncrewed test flight around the moon and back. The space agency plans to send four more Artemis missions, at least, over roughly a decade. Each mission will grow in complexity, evolving from uncrewed and crewed test flights to extended stays by astronauts on the moon, where they'll work with rovers, robots, and Earth-based scientists to configure the basecamp and investigate the glowing celestial body.

"This time around, the mission isn't a one-and-done race to a finish line. It's our step off the planet, a long-term bet on building a sustainable presence beyond Earth."
Andrew Driesman
Mission area executive, Johns Hopkins Applied Physics Laboratory

Named after Apollo's twin sister, Artemis, in ancient Greek mythology, the mission series honors the legendary goddess reputed for her prowess as a huntress who uses moonlight to guide her ventures in the wilderness. The program is aptly named, considering it will make Christina Koch, a former electrical engineer at APL, the first woman to reach Earth's satellite. Reid Wiseman, Engr '06 (MS), will serve as commander of the daring voyage designed to usher in a new era of moon missions, setting in motion NASA's plans to build a lunar basecamp and eventually make it to Mars.

But pulling off Artemis won't happen easily. "Every part of every Artemis mission involves major feats of science and engineering," Driesman says. A systems engineer by training, Driesman managed the development of the Parker Solar Probe mission that launched in 2018, with plans to fly through the sun's corona. Unlike Icarus of Greek legend, the spacecraft made it out with all parts intact, having flown closer to the sun than any other human-made object—and it is still flying today.

In his current role, Driesman oversees the development and operations of not only the Parker Solar Probe but also other space missions at APL, from the Lunar Vertex rover heading to the moon this spring to the rotorcraft Dragonfly destined to land on and investigate Saturn's largest moon, Titan. Likewise, his colleagues are involved in Artemis-related projects at APL, home to one of the largest groups of lunar scientists in the world, with many playing leading roles in NASA's audacious moon return.

"I'm at an age where there's no way I'll go to space, but it's incredible to live through and be part of these experiences," Driesman says. "Whereas Apollo created the first golden space age, we're now in the second golden space age, driven by NASA and [an abundance of] commercial investments" that have created a fervent, competitive environment.

Image of a rocket with the moon in the background

Image credit: Photograph NASA Kennedy Space Center/NASA/Ben Smegelsky

Although APL once partnered primarily with NASA and other government agencies and universities, "we now also partner with industry," he explains. "It's completely changed everything."

Another factor fueling the acceleration of space exploration is the lower price-point of a launch. "Twenty years ago, it cost between $10,000 and $20,000 per pound [to pay for the fuel and equipment] to get something into space," Driesman says. "It's a tenth of that now thanks to prefabricated parts and reusable rockets. This is why we're seeing entrepreneurs investing."

But a basecamp and extended human presence on the moon present hefty challenges. There, lunar dust can cut like glass through lung tissue, and the lack of a protective atmosphere or magnetic shield makes sickness or death from high radiation levels, or annihilation from a meteorite or sun flare, plausible scenarios. "To put it in perspective, the International Space Station, where astronauts spend months at a time, resides in low-Earth orbit roughly 250 miles away," Driesman explains. "The moon, however, is 250,000 miles away, outside of the Earth's magnetic field that protects us. If a particle comes streaming out of the sun, it will not get deflected, and any human staying for longer than a short visit is susceptible to [its ill effects]." Another threat exists with meteorites, small space rocks that bombard the moon every day at a speed of between 45,000 and 160,000 miles per hour, with no atmosphere to slow or stop them.

Keeping humans safe from life-threatening hazards isn't the only challenge involved in the U.S. moon return. Now ubiquitous technological infrastructure like GPS navigation and 5G connectivity must be put in place. Driesman says that materials scientists, chemists, physicists—every engineering discipline you can imagine—are involved in trying to understand and build the lunar infrastructure that would survive the high-radiation environment.

With such laborious tasks and potential deathtraps, why even attempt to build an outpost on the moon? What can it offer life as we know it on Earth?

As a child, planetary geologist Rachel Klima used to imagine the moon winking at her on family road trips. Now, when she looks up at the moon, she scrutinizes its signature swirling dark patterns visible with the naked eye from Earth. "The dark patterns are massive lava plains (also known as maria) made of the charcoal-colored volcanic rock basalt," Klima says. "When I look at lava plains in the infrared, one shows a whole circus of color, indicative of different mineralogy, so I think about all the cool rock types up there when I stare at the moon from my backyard."

At APL, Klima is the director emeritus and now serves as the lunar technology and science adviser of a major NASA program, the Lunar Surface Innovation Consortium (LSIC). An international collaboration run out of APL's main campus in Laurel, Maryland, LSIC brings together the brainpower of 300-plus universities, government agencies, private companies, and nonprofit organizations, working to create the technologies and systems needed for Artemis and a basecamp on the moon's far side. Part of that initiative involves learning how the universe and individual planets formed. The moon is the most suitable place to do that, according to NASA.

"The moon can help us answer fundamental questions about how rocky planets evolved in the solar system, including Earth," Klima says. "It's basically our Rosetta Stone because of its constant bombardment by [space] debris over billions of years, and we can use samples brought back [from Artemis and other missions] to date things that happened on other planets and in the universe."

"The moon can help us answer fundamental questions about how rocky planets evolved in the solar system, including Earth. It's basically our Rosetta Stone because of its constant bombardment by [space] debris over billions of years."
Rachel Klima
Planetary geologist, Johns Hopkins Applied Physics Laboratory

Lunar samples from Apollo have provided clues to the formation of celestial bodies, including the discovery that both the moon and Earth formed from hot (molten) origins, not cold origins, as previously thought. But there's much more to learn "and dozens of questions for every partial answer," Klima says. One of those questions: Does life exist elsewhere? For astronomers, the far side of the moon is the place to search for evidence, offering prime spots for telescopes to capture pristine views of deep space, unimpeded by atmospheric effects like wind, clouds, and rain. Here, "[we could] avoid radio interference from maritime radars, cellphones, and other activities, as well as—and even more distracting—the effects of the terrestrial ionosphere, through which the signals [create problems]," says cosmologist Joseph Silk, author of Back to the Moon: The Next Giant Leap for Humankind (2022) and a physics and astronomy professor in the Johns Hopkins Krieger School of Arts and Sciences. Earth's ionosphere, the charged particles and blurring effects of the atmosphere, pose difficulties for the next generation of telescopes. But those problems don't exist on the lunar far side. "There, we could tune in at very low radio frequency levels to peer back into the dark ages, long before stars formed, to see the elusive clouds of gas that were the building blocks of galaxies," Silk says.

The area's natural resources also make it ideal for a basecamp, though scientists need to determine what exactly they can access there, and where. One of the most vital resources is water frozen deep within craters on the moon's polar regions, which could be mined to generate drinking water. Likewise, by mixing water with regolith (the lunar dust and surface material made of fragmented debris), construction materials or even rocket fuel could be created. "Hydrogen and oxygen could be liquified to produce rocket fuel, which you could use to travel around the moon and eventually throughout the solar system, without the exorbitant cost of launching spacecraft from Earth," Silk explains.

But water isn't the only resource making the ice-filled craters a suitable location. Many of the craters are encircled by high rims. The sun never sets on some of the rims, so they're permanently illuminated—and perfect for creating "an inexhaustible supply of nearby solar power," Silk says. This, combined with water access, may make it possible for crews to develop the basecamp largely in situa focus area of LSIC, whose teams are devising ways to excavate and build with what's on hand. "Instead of sending supplies from Earth, we're figuring out how to utilize and recycle everything the moon offers, in ways that work in a place where temperatures can swing from, say, 220 degrees Fahrenheit during the day to minus 250 or more at night," Klima says. Lunar dust is another hurdle. "It's sharp, angular, sticky, and toxic," Klima explains. "It clings to everything and can gum up mechanical systems, while wreaking havoc on human health, so we have to figure out how to deal with it."

For NASA, the lunar landscape is key to reaching its more daunting destination: Mars. High radiation levels, extreme temperature fluctuations, and a thin atmosphere make survival on Mars much like that on the moon. As such, NASA and its partners plan to use the moon as a proving ground, applying lessons learned there to its long-term goal to send humans to the Red Planet—a goal slated for the 2030s but deemed impossible now due to a lack of technology. The trip alone, estimated to take at least seven months, would subject astronauts to "vital organ deterioration, bone marrow damage, stem cell destruction, and tissue necrosis," Silk says. "Assisted only by current technology, astronauts would arrive there saddled with muscular atrophy and riddled with cancers."

Much needs to happen before a Mars mission becomes conceivable, Silk indicates. Yet with Mars on the horizon—and a long-term objective of NASA's Artemis program—the moon presents a better launchpad to the Red Planet than does Earth, mostly owing to gravity. "From an orbit perspective, once you're outside of Earth's gravity well and set up, for instance, on the far side of the moon, it takes less fuel and energy to get to Mars," Driesman explains.

But the moon beckons for other reasons, too, including its potential for commercial ventures like space tourism and mining. "The amount of elements to mine there is enormous, including rare elements that we'll eventually run out of on Earth and that produce incredible toxicity when we mine them here," Silk says. "On the moon, these elements didn't burn up in an atmosphere and are strewn across the lunar surface, having been deposited there for billions of years by asteroids and meteorites." One example is the rare metal europium used in computer chips, flash drives, smartphones, and other pieces of our technological infrastructure. "If we want to keep evolving our technology, including technologies to fight Earth's climate change like wind turbines and electric vehicles, then we're going to need these elements," Silk says.

Yet for any of this to happen, humans must first return to the moon after a hiatus of more than a half-century.

With plans for repeat trips to the moon and beyond, carrying humans and heavy technological and scientific equipment, the Artemis missions hinge on the success of NASA's new spacecraft, Orion. NASA says the spacecraft made it to the moon and back without docking for refueling and reached a reentry speed of roughly 25,000 mph—32 times the speed of sound. But the heavy spacecraft couldn't lift off from Earth without NASA's new Space Launch System rocket, designed to generate an unprecedented 8.8 million pounds of thrust to propel Orion through the pull of gravity.

The first mission, Artemis I, took place in November 2022 without astronauts on board—a 25-day test run to make sure everything functioned properly. Launching from Cape Canaveral, Florida, Orion traveled 268,563 miles, reaching a destination of roughly 40,000 miles beyond the moon before returning to Earth, where it splashed down near Baja California, in the Pacific Ocean.

Artemis II, now planned for September 2025 (after a full-year delay owing to technology difficulties), will send four astronauts into high Earth orbit, without touching down on the moon but traveling 4,600 miles beyond its far side. The mission will take approximately 10 days and involve more testing of Orion's capabilities and operating systems, particularly those designed to keep humans safe amid dangerous conditions.

"I can't wait to fly Orion," says Wiseman, appointed as the Artemis II crew commander. "It's like no other flying machine." Wiseman grew up in Baltimore County, graduating from Dulaney High School before setting off for college at Rensselaer Polytechnic Institute and becoming an aviator in the U.S. Navy. There, he learned the ins and outs of fighter jets like the Super Hornet and Lightning II, deploying twice for operations in and around Iraq and earning entry to the prestigious U.S. Naval Test Pilot School. In 2009, after finishing his graduate degree at Johns Hopkins, Wiseman became one of only nine people to join NASA's 20th astronaut class.

Wiseman took his first trip to space in 2014 as a flight engineer aboard the International Space Station, spending 165 days working with crewmates on scientific experiments related to human physiology, medicine, physical science, and astrophysics. His team set a milestone for completing 82 hours of station science in a single week, with Wiseman spending 13 hours on spacewalks repairing and installing equipment. "The whole experience blew me away," he says. "Aside from just being out there and taking in my surroundings, I formed incredible bonds with crewmates from Russia and Germany and worked with super smart scientists leading research efforts back on Earth."

Now, as he prepares for Artemis II, he says he could write a book on what excites him about the mission and his role as the first astronaut to fly Orion through space. "Orion's propulsion system is pretty far-reaching, and I can't deny the thrill of that, but really I can't wait to fly it to honor the countless people from across the country and world who put their blood, sweat, and tears into building it," Wiseman says. "Orion looks like an Apollo spacecraft on the outside, but inside, the amount of automation and [backup systems] makes it very neat for a space geek and test pilot like me to learn about and fly."

"I can't wait to fly [Orion] to honor the countless people from across the country and world who put their blood, sweat, and tears into building it."
Reid Wiseman
Astronaut, NASA

Wiseman looks forward to sharing the experience with U.S. crewmates Koch and Victor Glover (who will be the first Black astronaut to travel around the moon), as well as Canadian astronaut Jeremy Hansen. He's especially in awe of their ability to complement each other's strengths and weaknesses, having learned, for instance, that he's less adept than others at handling some of the physical discomforts of space exploration.

"The military taught me to be in extremely uncomfortable environments and survive, but adjusting to [disorientation caused by] the lack of gravity on the ISS taught me that some people are incredibly good at physical discomfort," Wiseman says. "I love being at sea, and I love hiking and looking over vistas," he explains, "but most of my exploration involves a team and is part of my profession." Wiseman says he admires many of his colleagues' inner drive for adventure, including his crewmate Koch. "Even in her spare time, she's pushing boundaries," he says. "One minute, she's going to Cabo to surf, and the next she's rock-climbing on the side of a mountain in Washington state."

Koch studied engineering and physics in college and graduate school at North Carolina State University, before working in research labs in some of the world's most remote locations. Her first venture, from 2004 to 2007, involved extended stays in the South Pole serving on the U.S. Antarctic Program's firefighting, search, and rescue teams. Then, in 2010, after two years at APL developing science instruments for NASA's Juno mission to Jupiter, she returned to Antarctica for another tour before spending several winters at a research station in Greenland. From there, her expeditions in secluded locales continued, sending her to Alaska's Arctic shores to work for the National Oceanic and Atmospheric Administration and, later, to a small island in the middle of the Pacific Ocean to serve as station chief at the American Samoa Observatory.

Four astronauts stand and wave while wearing orange jumpsuits

Image caption: Artemis II crew members (from left): Canadian astronaut Jeremy Hansen and NASA astronauts Christina Koch, Victor Glover, and Reid Wiseman

Image credit: NASA/Kim Shiflett

"I've always loved the idea of science and exploration on the frontiers," Koch told a crowd of lunar scientists and engineers—many her former colleagues—during a colloquium at APL this past fall. "As a kid, I had posters of Antarctica up in my room and dreamed of living through the long polar night and seeing the beautiful aurora." Her time in Antarctica and other far-off places, she told the crowd, prepared her well for entering NASA's astronaut class in 2013 and then spending more time than any other woman astronaut on Earth's most remote research station, the ISS. During her record 328-day stay there in 2019, she conducted more than 42 hours of spacewalks, including the world's first three walks involving only women.

Koch returned to Earth with her legs and limbs feeling as though weighed down with bowling balls, a common effect of returning to gravity. People were abuzz about her achievements, but she didn't want fanfare. "My buddy Chuck [Schlemm], an engineer I worked with at APL, emailed to congratulate me, and I wrote him back downplaying it all, saying, 'Chuck, I'm not doing any of this for notoriety,'" Koch said. "[Chuck responded,] telling me that milestones help the public understand what we're doing in space and what it means to push boundaries. Ever since that moment, he changed my attitude on that."

With Artemis II, Koch and the other astronauts are gearing up to set another milestone as they hurtle through space to a place no humans have gone, with the critical role of testing Orion's operating systems. Among the crew's long project list is to evaluate the spacecraft's translunar injection burn that will send them soaring around the back side of the moon. In addition, they'll test Orion's communication capabilities in deep space and measure matters of human safety and health, looking specifically at the cabin's ability to remove carbon dioxide and generate breathable air (through oxygen and nitrogen systems), control temperatures, prevent and detect fires, and gauge and protect astronauts from radiation exposure. They'll even monitor everyday matters like food storage and excrement disposal—an unappealing task in the cramped confines of a place where food and body odors linger, with no window to let in fresh air. All the while, they'll wear monitors to track vital signs as they go about their day, sleep, eat, and exercise.

Although Koch and Wiseman look like icons of health and fitness, they both know how hard the gravity-free zone of space is on the body. "I worked out for two hours every day on the ISS but still lost muscle and bone density, at a rate of someone with osteoporosis," Wiseman says. Studies show that extended stays in places with low or no gravity and high radiation levels can cause other medical problems, from cardiovascular damage and cancer to ocular difficulties and cognitive decline. "In microgravity, your heart doesn't work as hard pumping blood," Wiseman explains. "You lose 25% of your blood volume, given that blood is equally distributed throughout the body, without gravity pulling the blood flow downward, as it does on Earth."

The Artemis II crew is thus devoting the pre-launch period not only to mission simulations but also to maintaining optimal fitness. For Wiseman, who lives in Houston and lost his wife, Carroll Taylor, to cancer in 2020, he additionally prioritizes time with his two teenage daughters. "This morning, I watched them drive off in a car together to high school," he says. "I'm an only parent, and my girls are my whole life."

On Orion, Wiseman and Koch will hook their sleeping bags to walls and get the eight hours of rest built into their schedules by NASA. They'll also exercise, utilizing a cable-based device for cardio and strength training. Mostly, though, they'll complete the tasks and tests needed to pave the way for Artemis III, slated to happen in September 2026, when the first humans will attempt to walk on the moon's far side.

NASA hasn't yet named the four Artemis III astronauts but says the precise destination is the lunar South Pole, where staggering temperature fluctuations and enormous mountains cast swaths of dark shadows that make the region hard to navigate.

To get there, astronauts will fly Orion to a position in lunar orbit. Two astronauts will leave the spacecraft behind as they transfer to a human landing system that will take them to and from the moon's surface and serve as a habitat during surface operations. Under development by Elon Musk's aerospace company SpaceX, the landing system, Starship, won't touch down on the moon but will hover above as an elevator descends to take astronauts and cargo to the South Pole. There, they'll spend six days—the time it will take Orion to complete a full orbit around the moon—investigating the landscape and conducting research, while beaming up as needed (to sleep and eat, for instance) to the floating lunar lander.

Artemis III is NASA's most ambitious mission to date. No doubt, it conjures scenes from Star Trek or the late sci-fi author Arthur C. Clarke, whose 1979 book The Fountains of Paradise describes an elevator stretching from Earth to outer space. Yet NASA says the mission is happening, with SpaceX claiming that Starship will someday carry "up to 100 people on long-duration, interplanetary flights." But the launch of Artemis III will depend on the timeline and findings of Artemis II, in addition to the development schedules of private companies (like SpaceX) partnering with NASA to pull off the mission. Delays are inevitable, and test runs are critical, APL's Driesman says.

Driesman conceives of each Artemis mission, and the many rovers sent to survey the moon, as learning opportunities to guide and refine future expeditions, he says. So far, NASA has released detailed plans for Artemis IV and V, with proposals underway and contracts awarded for additional missions extending to the 2030s. But skeptics worry the timeline is too tight, with NASA's own Aerospace Safety Advisory Panel saying "there will be extraordinary pressure for timely execution of a schedule that in many ways is beyond NASA's full control, and at a level of integrated risk that will challenge the workforce to the extreme."

Whether NASA will build in more time remains to be seen and depends in part on geopolitics—and a space race that differs from the one that fueled Apollo. "There is definitely a race to the moon right now between NASA, with its partners in Europe and elsewhere, and China," Silk says. "Both sides are racing to get boots on the moon and build outposts there." The problem is, Silk contends, that although competition among nations is the very thing igniting the moon return, it poses a threat to international relations and world stability, opening the door to jockeying for resources and property. The United Nations' Outer Space Treaty, developed in 1967, attempted to solve the problem of nations laying claim to portions of celestial bodies. "More than 120 countries have signed the treaty, including the U.S. and China, but there's no legal basis to enforce it," Silk says. "[Combine that with] the limited sites on the moon suitable for scientific research and exploits like mining and tourism, and the race and tensions intensify."

In 2020, NASA and the U.S. State Department drafted a similar treaty, the Artemis Accords, with seven other founding member nations—Australia, Canada, Italy, Japan, Luxembourg, the United Arab Emirates, and the United Kingdom. At the time of this writing, 34 additional nations have signed the nonbinding principles created to guide the peaceful exploration of space, encourage transparency and collaboration, and protect space from pollution. But critics say the Artemis Accords violate the U.N.'s Outer Space Treaty because the agreement permits nations to keep (and therefore own) the resources they extract from celestial bodies. Thus, the Accords and overarching plan to build a lunar basecamp hold the potential to heighten conflict—and inequity—among nations on Earth, says Silk, adding: "We need clearer rules and oversight. We need to avoid a Wild West scenario."

"Humanity, with a presence outside of Earth, could weaponize space and wage war at a level we've only seen in movies. ... If we go back to the moon, it should be for science."
Daniel Deudney
Political scientist, Johns Hopkins Krieger School

Geopolitics and international relations expert Daniel Deudney, a political scientist at Johns Hopkins' Krieger School, shares a similar view. "Although [space] expansionists claim space ventures will benefit all humanity, they also anticipate special advantage to those who undertake them first, while peoples who fail to seize opportunities for space expansion will fall behind," Deudney writes in this 2020 book, Dark Skies: Space Expansionism, Planetary Geopolitics, and the Ends of Humanity. Here, Deudney argues that plans to develop the moon and Mars could create a perfect breeding ground for conflict. "The reason is that humanity, with a presence outside of Earth, could weaponize space and wage war at a level we've only seen in movies," he says. History shows us, for example, that once a colony grows large enough, inhabitants tend to fight for independence, a terrible predicament for space. "Objects travel at incredible velocities in space, releasing enormous amounts of energy when they strike something," Deudney explains. "Once humans start using materials from asteroids and altering their orbits, they will have created an extraordinarily potent weapons potential."

Even still, Deudney isn't opposed to space exploration for the right reasons. "If we go back to the moon, it should be for science," he says, echoing a sentiment of many space scientists and enthusiasts at Johns Hopkins and elsewhere, who view the moon return as a must for advancing knowledge and expanding our frontiers. But doing it responsibly warrants careful consideration. "Above all, let's not re-create the mistakes made on Earth," Silk cautions.

For Klima, the planetary geologist at APL helping to spearhead LSIC, an ideal lunar basecamp is a conglomerate of science stations where countries work together for the greater good—much like the 70 research stations of 29 countries scattered across Earth's South Pole, an outcome of the Antarctic Treaty created in 1959 to foster cooperation among explorers and scientists. She pictures the basecamp operating in a way that preserves the moon's natural environment, with lessons carried there from humanity's infighting and denigration of its own planet.

"The moon is a difficult space to navigate because it's been our celestial neighbor since humanity evolved, and it's special to so many people's cultural heritage and upbringing," Klima says. "As a community of scientists, we can't dismiss those who hold beliefs about the moon. We can't harm the environment, and we can't endanger relationships." Instead, Klima suggests, she and her colleagues owe it to the world to respect those concerns as they use science to unravel the universe's great mysteries.

Will they find life? Will they uncover the origins of our existence or find ways to protect our oasis on Earth? All eyes will be on Artemis.

Emily Gaines Buchler is a senior writer at Johns Hopkins University.