Skip to main content

Artemis 1: Going back to the moon

An artist's impression of the Artemis 1 Orion capsule speeding away from Earth.
An artist's impression of the Artemis 1 Orion capsule speeding away from Earth. (Image credit: NASA)

The Artemis 1 mission will mark a big step in humanity's return to the moon.

2022 marks half a century since Apollo 17 astronaut Eugene Cernan left the last footprints on the moon in 1972, and a lot has changed since then. 

That year, the first scientific hand-held calculator was released; today we carry more computing power in our pocket than that which safely guided the Apollo astronauts to the moon and back. 

Now, at long last, humanity is about to leave low Earth orbit (LEO) again. Only two dozen astronauts have achieved that feat so far, all of them white men. Soon the first female astronaut and first astronaut of color will join the lauded lists of moonwalkers. It's all thanks to the Artemis program, NASA's plan to explore more of the lunar surface than ever before. 

By 2025, we could see astronauts walk in the lunar dust once more, with the upgrade from grainy black and white video footage that half a century of technological progress has brought. A whole new generation could see themselves as budding space travelers, inspired to dream big.

But pulling off this next moonshot requires an entirely new launch system and a bit of practice first. 

Related: Every mission to the moon

The Space Launch System rocket

The uncrewed Artemis 1, which is expected to launch in August or September 2022, will mark the debut of NASA's huge Space Launch System (SLS) rocket. 

The new megarocket will send the Orion capsule on a roughly four-week journey around the moon. If all goes according to plan, the Artemis 2 mission will follow in 2024, sending astronauts around the moon and back. 

Artemis 3 will put astronauts down on the moon, near the lunar south pole, with the aid of SpaceX's Starship vehicle. This landmark mission is targeted for 2025 or 2026. 

Even without a crew, Artemis 1 will be a record-breaker. According to NASA (opens in new tab), "Orion will stay in space longer than any ship for astronauts has done without docking to a space station and return home faster and hotter than ever before." 

But first Orion has to leave Earth.

Two huge solid rocket boosters and a core stage filled with 733,000 gallons (2.8 million liters) of propellant will power Orion through Earth's atmosphere to orbit. The SLS upper stage, known as the Interim Cryogenic Propulsion Stage (ICPS), will then fire to send Orion toward the moon.

Once the ICPS has fired, it has another job: to deploy 10 tiny cubesats that are hitch-hiking aboard Artemis 1. These little spacecraft include BioSentinel, a mission that will carry yeast samples beyond LEO. The idea is to study radiation levels and their effect on living organisms, which will provide key insights in keeping astronauts safe when they fly on future Artemis missions.

After separation from the ICPS, Orion will be propelled and powered by the European Service Module, built by the European Space Agency (ESA). "The Service Module will also provide consumables for future crew, including water and oxygen," said Phillippe Berthe, ESA's project coordination manager for the module.

Artemis 1 may not have a human crew on board, but the commander's seat will be occupied by a mannequin dressed in the Orion Crew Survival System, a special suit designed to help protect against radiation. Two radiation sensors will monitor radiation levels during the flight.

The mannequin will be strapped in, but the weightless environment also needs testing. So NASA is flying a "zero gravity indicator" in the form of a Snoopy cuddly toy dressed in an iconic orange NASA jumpsuit. The comic strip character has a long association with lunar exploration; the crew of Apollo 10 nicknamed their lunar module Snoopy.

So how does the new Orion service module compare to the lunar modules that sent Apollo astronauts to the moon? "The propulsion is largely the same; it is very comparable to the Apollo era," said Berthe. Yet half a century of technological progress has brought other strides forward. “There have been vast improvements in solar cells,” Berthe said. 

"Computing power is another major improvement," said Berthe. The Apollo astronauts famously flew to the moon with less computing power than found in an iPhone. That meant a lot of manual tasks for the crew. This time around, the spacecraft's powerful computers can do most of the heavy lifting. 

"We can program much more complex operations now. The crew don't need to intervene directly in every nitty-gritty detail," Berthe said.

The Artemis 1 flight plan

Artemis 1 will be gone for between 26 and 42 days. It'll take one to two weeks to get to the moon, where Orion will swoop down close to the lunar surface and use the gravitational kick it receives to enter a so-called "distant retrograde orbit." 

Retrograde means that it will orbit the moon in the opposite direction to that in which the moon spins. Orion will stay in that orbit for between six and 19 days. Then it will swing back down toward the moon for another kick to help power its nine- to 19-day journey back to Earth.

 This project has been a labor of love for Berthe, who has been involved with it for nearly two decades and has seen many obstacles come and go. 

"One of the biggest challenges has been maintaining support across four administrations," he said.

The administrations of the U.S. presidents Bush, Obama, Trump and Biden have all put their own spin on the nation's human spaceflight program, shifting NASA's focus from the moon to an asteroid and then back to the moon again over the years.  

Artemis timelines have also moved around; President Trump targeted 2024 for the programs' first crewed lunar landing, for example.  

"The mission has changed a lot of times," Berthe said.

On top of the politics came the coronavirus pandemic, which certainly didn't help . But Berthe said the pandemic didn't have as big an impact as he had feared. "It was difficult for people to cross international borders," he said, noting that complication "somewhat slowed us down."

There have also been plenty of Artemis naysayers — those who argue that sending humans back to the moon is a waste of time, money and resources. We've already done it, such people say, so why go back, especially since humanity has already sent an armada of robotic spacecraft to both scan the moon from orbit and drive across the lunar surface. 

Berthe has an answer for that question.

"An astronaut will do in a six-hour [moonwalk] what a robot can do in six months," he said. “It is more expensive, but it is more efficient."

We ultimately also want more than just fleeting visits. 

"We want to stay permanently and build something sustainable for the long run," Berthe said. Indeed, Artemis aims to establish a sustainable human presence on and around the moon by the end of the 2020s, NASA officials have said, stressing that the program will also serve as a steppingstone toward Mars, where the agency wants to send astronauts in the 2030s.

And Artemis isn't just about the lunar surface; a moon-orbiting outpost called Gateway is a big part of the program. Think of it like an International Space Station, but in orbit around the moon. A home considerably-farther-away from home. Gateway could be ready as soon as November 2024, and it is intended to last for 15 years.

While aboard Gateway, astronauts will stay in the Habitation and Logistics Outpost (HALO). There are also additional docking ports for cargo ships to come and go with supplies. Astronauts would then transfer to the Starship Human Landing System (HLS), a lunar lander based on SpaceX's existing Starship. 

Initially stays will be short and largely inside the lander, but ultimately NASA wants astronauts living on the lunar surface, at Artemis Base Camp, for at least a month at a time. In September 2021, the agency put out a call for companies to submit their proposals for the next generation of spacesuits that Artemis astronauts will wear during their history-making moonwalks.

Artist’s concept of a future moon landing carried out under NASA's newly named Artemis program. The space agency is working to return men and send the first women to the lunar surface by 2024, as has been directed by the White House.

An artist's depiction of astronauts working on the lunar surface. (Image credit: NASA)

After Artemis 1

Eventually the space between the Earth and the moon could be swarming with spacecraft ferrying goods and astronauts back and forth. Jeff Bezos, the founder of Amazon and the spaceflight company Blue Origin, has suggested that the moon could be a place to put our heavy industry. Doing so would free up living space on Earth and move our atmosphere-polluting infrastructure somewhere where there isn't even an atmosphere, the idea goes.

The moon is also an ideal staging post for deeper solar system exploration, experts say. The size and scale of the SLS shows just how hard we have to work to escape from Earth's gravitational clutches. The moon's gravity, which is six times weaker than ours, is considerably easier to flee from. There are also huge amounts of water on the moon. As water is H2O, that means an abundant supply of oxygen. In fact, the moon's top layer alone has enough oxygen to sustain 8 billion people for 100,000 years, researchers have calculated. Liquid oxygen is also rocket propellant, so moon mining could lead to the creation of off-Earth "gas stations" where voyaging spaceships could fill up their tanks.

How rockets work: A complete guide

That's why Artemis Base Camp will be at the moon's south pole: We already know that there's plenty of water there. Lunar Flashlight, one of the small spacecraft hitching a ride on Artemis 1, will orbit the moon and shine infrared lasers into permanently shadowed craters near the lunar poles to further reveal the quantity and accessibility of water ice there.

The sunlight at the lunar south pole is also favorable; it is illuminated approximately 90% of the time, compared to two weeks of daylight followed by two weeks of darkness on the rest of the moon. That's good news for a lunar outpost powered by solar panels. The combination of these two factors — water and sunlight — may lead to a time when rocket ships routinely fuel up close to Artemis Base Camp and blast off for more distant climes such as Mars and the asteroid belt.

Former NASA chief Jim Bridenstine certainly sees lunar exploration as a key step on our journey toward becoming an interplanetary species. He has said that humanity needs "several years in orbit and on the surface of the moon to build operational confidence for conducting long-term work and supporting life away from Earth before we can embark on the first multi-year human mission to Mars."

It's all part of returning to where we came from. The iron in your blood and the calcium in your bones was forged inside stars that blasted these elements across the universe when they died. Eventually those atoms found themselves inside sentient creatures who dreamed of sailing between the stars and built cathedral-sized rocket ships to take them there. 

The Artemis 1 launch this year may only be a small step, but it's an important one. Future historians could look back on it as the moment humanity took a giant leap in its return to the moon, this time for good.

Additional resources

For more information about the Artemis 1 mission and to receive live updates, check out NASA’s Artemis 1 webpage (opens in new tab). The European Space Agency has also put together this animation (opens in new tab) to visualize the mission.


Follow us on Twitter @Spacedotcom (opens in new tab) or on Facebook (opens in new tab)

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at:

Colin Stuart
Colin Stuart

Colin Stuart is an award-winning astronomy author, speaker and tutor based in the UK. His popular science books have sold over 400,000 copies worldwide and have been translated into 21 languages. The asteroid (15347) Colinstuart is named after him and he runs an online Astrophysics for Beginners course and a science writing course.