Wikipedia Deep Dive

Artemis program

16 min read

Half a century ago, humans walked on the Moon. Then we stopped. For fifty years, no one has left footprints in lunar dust or watched Earth rise over a gray horizon. The Artemis program aims to change that—and this time, the plan is to stay.

But here's what makes Artemis truly remarkable: it's being built from the bones of failed programs, repurposed shuttle engines from the 1980s, international partnerships, and billionaire rocket companies. It's simultaneously the most ambitious human spaceflight program since Apollo and a patchwork of political compromises, budget battles, and technological gambles.

Why "Artemis"?

In Greek mythology, Artemis was Apollo's twin sister—the goddess of the Moon, the hunt, and the wilderness. The name is both poetic symmetry and a statement of intent. Where Apollo proved we could visit the Moon, Artemis promises we can live there.

The ultimate goal isn't just returning astronauts to the lunar surface. It's establishing a permanent base on the Moon that will serve as a proving ground for the technologies and techniques needed to send humans to Mars. Think of the Moon as a dress rehearsal for the main event—close enough to Earth for rescue if things go wrong, far enough to test whether humans can truly survive in deep space.

The Long Road to Launch

Artemis didn't spring fully formed from NASA's planning documents. It's the survivor of decades of false starts, cancelled programs, and shifting political winds.

The story really begins in 2005, when NASA started the Constellation program under President George W. Bush. Constellation was supposed to return Americans to the Moon by 2020 using two new rockets called Ares I and Ares V, plus a spacecraft called Orion. But by 2009, an independent review committee delivered a damning verdict: Constellation was "massively underfunded," and a 2020 Moon landing was impossible.

President Obama cancelled most of Constellation in 2010, keeping only the Orion capsule. He redirected NASA toward developing a new heavy-lift rocket and set a goal of reaching Mars orbit by the mid-2030s. The Moon, in Obama's vision, was a distraction. "We've been there before," he said.

Congress disagreed. Legislators mandated the development of what became the Space Launch System, or SLS—a massive rocket that would preserve the workforce and capabilities of the Space Shuttle program. The SLS was supposed to be ready by 2016.

It wasn't.

Trump, Pence, and the Push to 2024

When President Donald Trump took office in 2017, human spaceflight policy shifted again. Trump signed Space Policy Directive 1 in December of that year, formally redirecting NASA back toward the Moon. The new campaign would eventually be named Artemis.

Then came the acceleration. In March 2019, Vice President Mike Pence announced that NASA would land astronauts on the Moon by 2024—four years earlier than planned. This wasn't just ambition; it was politics. A 2024 landing would happen during a potential second Trump term, giving the administration credit for a historic achievement.

The 2024 deadline proved unrealistic. Technical challenges, budget shortfalls, and a global pandemic pushed the schedule back. As of late 2025, the first crewed lunar landing isn't expected until mid-2027 at the earliest.

The Rockets and Spacecraft

Understanding Artemis requires understanding its hardware, and that hardware tells a fascinating story of pragmatism, recycling, and engineering compromise.

The Space Launch System

The SLS is the most powerful rocket NASA has ever built—more powerful than the Saturn V that sent Apollo astronauts to the Moon. It stands taller than the Statue of Liberty and generates 8.8 million pounds of thrust at liftoff.

But here's the remarkable thing: much of the SLS is recycled from the Space Shuttle program. The four main engines on the core stage are refurbished RS-25 engines that actually flew on Space Shuttle missions. Some of these engines date back to the early 1980s. The two solid rocket boosters strapped to the sides are evolved versions of the Shuttle's boosters.

For Artemis I through Artemis IV, every main engine that roars to life will be a veteran of the Shuttle era. The same is true for the solid rocket boosters through Artemis III. NASA is literally launching the future using engines from the past.

This approach has critics. Why build an expensive expendable rocket when companies like SpaceX are developing reusable ones? The SLS costs roughly two billion dollars per launch, and you can't use it twice. But the SLS exists now, it works, and it's the only rocket currently capable of sending the Orion spacecraft to lunar orbit.

The Orion Spacecraft

If the SLS is the muscle, Orion is the brains and the beating heart. This capsule is where astronauts will live during their journey to and from the Moon.

Orion looks like a larger, more capable version of the Apollo command module—a gumdrop-shaped capsule with a heat shield for atmospheric reentry. But it's far more sophisticated than its 1960s predecessor. It can support four astronauts for up to 21 days, compared to Apollo's three astronauts and roughly two-week maximum.

The spacecraft actually has two parts: the crew module built by Lockheed Martin in the United States, and the European Service Module built by the European Space Agency. That service module, which provides propulsion, electricity, and life support, makes Artemis a genuinely international endeavor from the very first mission.

And like the SLS, Orion carries Space Shuttle heritage. Its main engine is the Orbital Maneuvering System engine from the Shuttle—another piece of 1980s technology repurposed for 21st-century exploration.

The Human Landing System

Here's where Artemis gets really interesting. The SLS and Orion can carry astronauts to lunar orbit, but they can't land on the Moon. For that, NASA turned to private industry.

SpaceX won the initial contract to build the Human Landing System, or HLS, using a modified version of their Starship vehicle. If you've seen videos of Starship test flights—the gleaming stainless steel towers launching and landing in Texas—that's what will carry Artemis astronauts down to the lunar surface.

The logistics are complex. Before any crewed landing can happen, SpaceX must launch a Starship to lunar orbit and refuel it there. That refueling requires multiple additional Starship launches carrying propellant. Only then can the SLS launch astronauts in Orion to rendezvous with the waiting lander.

For Artemis V and beyond, Blue Origin—Jeff Bezos's space company—will provide an alternative lander called Blue Moon. Competition and redundancy: NASA has learned from past programs that relying on a single provider creates unacceptable risk.

The Mission Sequence

Artemis is organized as a series of increasingly ambitious missions, each building on the last. Think of it as climbing a staircase to the Moon.

Artemis I: Proof of Concept

The first step happened in November 2022, when an uncrewed Orion spacecraft launched atop the SLS for the first time. No humans aboard—just mannequins and sensors designed to measure what astronauts would experience.

Orion traveled to the Moon, entered a distant retrograde orbit (essentially circling the Moon in the opposite direction of the Moon's rotation around Earth), and spent about six days in lunar space before heading home. The capsule splashed down in the Pacific Ocean under parachutes, validating the entire system.

It worked. Artemis I proved that the SLS could launch and that Orion could survive the punishing heat of reentry—temperatures exceeding 5,000 degrees Fahrenheit, half as hot as the surface of the Sun.

Artemis II: Humans Return to Lunar Space

Scheduled for early 2026, Artemis II will carry the first crew on the SLS and Orion. Four astronauts will spend about ten days in space, performing extensive testing in Earth orbit before a trajectory that will swing them around the Moon and back.

This is a "free-return" trajectory, meaning the spacecraft will use the Moon's gravity to sling itself back toward Earth without needing to brake into lunar orbit. It's the same technique Apollo 13 used when an explosion forced that crew to abort their landing and return home.

Artemis II won't land on the Moon or even orbit it. But it will take humans farther from Earth than anyone has traveled since Apollo 17 in 1972. The four crew members will see the far side of the Moon with their own eyes—something only 24 people in human history have ever done.

Artemis III: Boots on the Moon

This is the main event. No earlier than mid-2027, two astronauts will descend to the lunar surface while their two crewmates remain in orbit aboard Orion.

The landing site will be near the Moon's south pole, a region never visited by humans. Why the south pole? Water ice. Scientists have confirmed that permanently shadowed craters near the lunar poles contain frozen water—a resource that could be extracted and used for drinking, growing food, and manufacturing rocket propellant. A Moon base that can produce its own fuel could dramatically reduce the cost and complexity of future missions.

The surface crew will spend about six and a half days on the Moon—far longer than any Apollo mission. They'll conduct at least two spacewalks, wearing new spacesuits designed specifically for lunar exploration. Then the Starship lander will carry them back up to rejoin Orion for the journey home.

Artemis IV and Beyond: Building a Presence

The missions after Artemis III begin assembling the infrastructure for permanent lunar presence.

Artemis IV, planned for late 2028, will see Orion dock with the Lunar Gateway—a small space station in lunar orbit. Think of Gateway as a waystation, a place where crews can transfer between Orion and their lunar lander, store supplies, and conduct research. The mission will deliver the I-HAB module, an international habitat module for Gateway.

Artemis V, targeted for early 2030, adds more Gateway components: a refueling module from the European Space Agency, a Canadian-built robotic arm system, and a rover that astronauts can drive on the lunar surface. This mission also marks the first use of Blue Origin's Blue Moon lander.

The schedule continues through Artemis VI (2031), VII (2032), VIII (2033), and beyond. Each mission adds capability: an airlock for the Gateway, a pressurized rover that astronauts can live in for weeks at a time, surface habitats, logistics supplies. By the mid-2030s, if all goes according to plan, astronauts will be staying on the Moon for extended periods, not just visiting.

The Lunar Gateway

The Gateway deserves special attention because it represents a fundamentally different approach to lunar exploration than Apollo took.

Apollo missions went directly from Earth to the lunar surface and back. Simple and elegant, but also limiting. Each mission was self-contained, carrying everything it needed.

Gateway creates a permanent platform in lunar orbit. Crews can dock there, transfer to landers, and return. Supplies can be pre-positioned. The station can serve as a staging point for missions to different landing sites, or even as a jumping-off point for missions deeper into space.

The station will orbit the Moon in what's called a near-rectilinear halo orbit, or NRHO. This unusual path takes the Gateway close to the lunar north pole, then swings it out to about 70,000 kilometers from the Moon before bringing it back close to the south pole. One orbit takes about a week.

This orbit has advantages and drawbacks. It requires very little fuel to maintain, and it provides good visibility of both lunar poles and continuous communication with Earth. But it also means the Gateway is often quite far from the lunar surface, making transfers to and from landers more complex.

Some critics argue that the Gateway adds unnecessary complexity. Why not just land directly, as Apollo did? NASA's response is that Gateway enables sustainable, flexible operations—exactly what you need if you're building a permanent presence rather than just planting flags.

International Partners and the Artemis Accords

Apollo was an American triumph, achieved with American technology and American astronauts. Artemis is deliberately, structurally international.

The European Space Agency provides Orion's service module. Canada is building the robotic arm for Gateway. Japan is contributing life support systems and logistics modules. The European Space Agency is also building the ESPRIT refueling module for Gateway.

And then there are the Artemis Accords—a set of bilateral agreements between the United States and participating nations establishing principles for peaceful, transparent, and cooperative exploration of the Moon. As of late 2025, dozens of countries have signed, including Japan, Canada, the United Kingdom, Australia, Italy, and many others.

These accords aren't just diplomatic niceties. They establish practical rules: signatories agree to register space objects, release scientific data publicly, provide emergency assistance to astronauts in distress, and avoid harmful interference with each other's operations. They also endorse the extraction and use of space resources—a potentially contentious issue, since the 1967 Outer Space Treaty prohibits national appropriation of celestial bodies but doesn't explicitly address private resource extraction.

Notably absent from the Artemis Accords are Russia and China, both of which are pursuing their own lunar ambitions. China has landed robotic spacecraft on the Moon and has announced plans for crewed lunar missions in the 2030s. The space programs of the world's major powers are, in a sense, racing again—though this time the competitors are very different than they were in 1969.

Commercial Partnerships

Perhaps the most revolutionary aspect of Artemis is how thoroughly it relies on private companies.

The Commercial Lunar Payload Services program, or CLPS, contracts private companies to deliver scientific instruments and other payloads to the lunar surface. These aren't NASA spacecraft with NASA logos; they're commercial landers operated by companies like Intuitive Machines, Astrobotic, and Firefly Aerospace. NASA is a customer, not an operator.

This represents a fundamental philosophical shift. In the Apollo era, NASA designed, built, and operated nearly everything. The agency was vertically integrated, controlling the entire technology stack from rocket engines to astronaut food. That approach worked brilliantly for winning the space race, but it was staggeringly expensive and difficult to sustain.

Artemis distributes capability across a constellation of contractors. SpaceX provides the lunar lander. Northrop Grumman builds Gateway modules. Blue Origin develops a competing lander. Axiom Space is designing new spacesuits. The theory is that competition drives down costs while spreading risk across multiple providers.

Whether this approach will actually prove cheaper and more sustainable remains to be seen. SpaceX's Starship program has faced its own delays and setbacks. The CLPS landers have had mixed results—some successful landings, some failures. But the model represents the direction NASA has chosen, betting that the commercial space industry has matured enough to handle human lunar exploration.

The Budget Wars

Space programs live or die by their budgets, and Artemis has faced constant financial pressure.

In 2019, NASA requested an additional 1.6 billion dollars for Artemis for fiscal year 2020. In 2020, the White House proposed a 12 percent budget increase, including 3.7 billion dollars specifically for the Human Landing System. These requests met resistance in Congress, where some legislators questioned the wisdom of an accelerated lunar program while the nation faced other pressing priorities.

The program's very survival came into question in the early 2020s as the economics of space launch changed dramatically. Companies like SpaceX demonstrated that reusable rockets could slash launch costs by an order of magnitude or more. Suddenly, the SLS—an expendable rocket costing two billion dollars per flight—looked like a relic of a bygone era.

Congressional debates about Artemis's viability intensified. Critics argued that NASA should abandon the SLS in favor of commercial alternatives. Defenders pointed out that the SLS was the only rocket currently capable of the mission, and that cancelling it would strand the Orion program.

Ultimately, Artemis was funded through passage of the 2025 One Big Beautiful Bill Act—a legislative vehicle that swept up numerous programs into a single package. The program survived, but the budget battles underscored its political vulnerability. Unlike Apollo, which benefited from Cold War urgency and bipartisan consensus, Artemis must justify its existence with each new Congress.

The Deeper Questions

Why go back to the Moon at all? The question matters, because the answer shapes how we judge Artemis's success or failure.

One answer is scientific. The Moon's south pole, with its water ice and permanently shadowed craters, offers research opportunities that didn't exist for Apollo astronauts. We can study the origins of the solar system by examining ancient lunar rocks, search for resources that could support human settlement, and use the Moon's far side as a platform for radio astronomy free from Earth's electromagnetic interference.

Another answer is geopolitical. China is building a lunar program. So is India. The United States has strategic interests in maintaining its leadership in space exploration, both for national prestige and for the practical capabilities that space programs develop. The technologies created for Artemis—advanced life support, radiation shielding, in-space propulsion—have applications far beyond the Moon.

A third answer is aspirational. There's something in the human spirit that wants to explore, to push boundaries, to see what's over the next horizon. The Moon is a stepping stone to Mars and beyond. Building the capability to live and work there is a prerequisite for becoming a truly spacefaring species.

But there's also skepticism. Some argue that robotic missions can accomplish most of the scientific objectives at a fraction of the cost. Others question whether the money would be better spent addressing problems here on Earth. The debate is genuine, and Artemis's supporters haven't definitively won it.

What Success Would Look Like

If Artemis succeeds—really succeeds, not just lands astronauts and declares victory—what would that look like?

By the mid-2030s, you might see a lunar outpost near the south pole. A pressurized habitat where astronauts can live for months at a time. A rover they can drive for days across the lunar surface, sleeping in its pressurized cabin, exploring far more territory than Apollo astronauts ever could. Mining operations extracting water ice. A nuclear power plant providing electricity. Regular flights delivering supplies and rotating crew members.

You might see the Gateway station serving as a transportation hub, with spacecraft arriving from Earth, transferring cargo and crew, and departing for the lunar surface. Commercial companies operating their own lunar services, selling propellant or research facilities to government and private customers alike.

And you might see the first missions departing for Mars, using technologies and techniques proven on the Moon. The lunar outpost as a testbed and a fuel depot, reducing the cost and risk of the ultimate journey.

This is the vision. Whether Artemis achieves it depends on sustained political will, continued funding, successful technology development, and a bit of luck. The history of human spaceflight is littered with ambitious programs that never reached their goals.

But for the first time in fifty years, humans are genuinely preparing to walk on another world again. The rockets are built. The spacecraft exist. The plans are detailed. And sometime in the next few years, if all goes well, we'll watch astronauts descend to the lunar surface once more—this time with the intention of staying.

Artemis is Apollo's twin sister. But where Apollo sprinted to the Moon and came home, Artemis aims to build a home there. Whether she succeeds will be one of the defining stories of this century.