Fifty years ago, three NASA astronauts splashed down in the Pacific Ocean, concluding the final Apollo mission. Less than a dozen years after President John F. Kennedy challenged the United States to commit itself to “landing a man on the moon and returning him safely back to the Earth,” that historic program had achieved its goals and ended.
Now, we’re going back. But this time will be different.
A pivotal moment for the return of crewed missions to the moon occurred at 1:47 a.m. EST on November 16, with the successful launch of Artemis I. NASA’s high-powered Space Launch System rocket roared and crackled as it lifted off the Florida coast on its maiden voyage. The rocket pushed the Orion capsule toward the moon, on a flight testing the technology that will eventually bring astronauts, both men and women, back to the lunar surface.
“It was just a spectacular launch,” says geologist Jose Hurtado of the University of Texas at El Paso, who works with NASA on mission simulations and programs to train astronauts in geology. “It really hits home to me what I love about space exploration, especially human exploration. It’s just an aspirational and inspirational spectacle, and I hope that everybody that was watching it got some of that inspiration.”
Now, the United States and China are leading the way to return humans to the moon. The two countries’ programs are massive and complex undertakings with potentially big payoffs. Both aim to boost scientific understanding about the moon and the early Earth, develop new technologies for space exploration and use on Earth, as well as set the stage for longer-term human space exploration.
Better than rovers
Apollo was “a technological program to serve political ends,” says space historian Teasel Muir-Harmony. It was rooted in the political tension and conflict between the United States and the Soviet Union. The program “was about winning the hearts and minds of the world public. It was a demonstration of world leadership … of the strength of democracy and then also of capitalism,” says Muir-Harmony, curator of the Apollo Spacecraft Collection at the Smithsonian National Air and Space Museum in Washington, D.C.
Apollo 11 astronauts Neil Armstrong and Buzz Aldrin took the first-ever steps on the moon on July 20, 1969. Over the next few years, 10 more American men hopped, skipped and even drove across the pewter-colored, lifeless terrain of our planet’s only natural companion. Apollo 17 was the final mission in that series of landings, ending on December 14, 1972 (SN: 12/23/72, p. 404). Once Apollo 17 astronauts Eugene Cernan and Harrison H. Schmitt left their footprints embossed in the lunar dust and joined Ronald Evans in the command module, humans stopped walking on the moon.
In the decades since Apollo 17, about two dozen spacecraft from various countries have visited the moon. Some have orbited, others have slammed into the surface so researchers could study the material in the debris of those collisions, and some have landed and brought lunar samples back to Earth (SN: 1/16/21, p. 7).
While these uncrewed spacecraft have made some big strides in lunar exploration, humans could do better. “Nothing can replace the value of having a human brain and human eyes there on the scene,” Hurtado says.
One moment during Apollo 17 makes his point. Schmitt, the only geologist to visit the moon, noticed a patch of lunar soil with a particular rusty hue. He walked over, contemplated the surroundings and realized it was evidence of a volcanic eruption. He and Cernan scooped up some of this orange soil for later Earth-based analyses, which revealed that the orange glass blobs in the soil did in fact form during a “fire fountain” explosion some 3.7 billion years ago.
That discovery supported the idea that the moon had hosted volcanoes in its youth, and additional analysis of the orange soil’s chemical composition hinted that the moon formed at around the same time as Earth. Scientists wouldn’t have had access to the orange soil if it wasn’t for Schmitt’s quick grasp that what he saw was important. “Probably the ultimate field tool is the well-trained human,” Hurtado says.
In his 2005 book, Roving Mars, planetary scientist Steven Squyres wrote: “The unfortunate truth is that most things our rovers can do in a perfect [Martian day], a human explorer on the scene could do in less than a minute.” Squyres, of Cornell University, led the Spirit and Opportunity rover missions to Mars (SN: 8/13/22, p. 20).
A long-awaited lunar return
Once Apollo ended, NASA shifted its focus to space stations to prepare for longer-term human spaceflight. Skylab launched in May 1973, hosting four crews of astronauts that year and the next. A few years later, the temporary station broke apart in the atmosphere, as planned. NASA’s next space station, the International Space Station, or ISS, was a larger, collaborative project that’s been hosting astronauts since November 2000. It’s still orbiting roughly 400 kilometers above Earth.
U.S. leaders have occasionally tried to shift NASA’s gaze from low Earth orbit, where the ISS flies, to a more distant frontier. Many presidents have proposed investments in different technology for different exploration goals and with different price tags. But by 2019, the plan was set: NASA would land humans on the moon’s south pole in 2024, though the timeline has since slipped.
“The first woman and the next man on the moon will both be American astronauts, launched by American rockets from American soil,” said Vice President Mike Pence in early 2019. Shortly after, NASA named this effort the Artemis program — after Apollo’s mythological twin sister.
The Artemis program is part of NASA’s Moon to Mars program, which aims to send humans farther into space than ever before. The moon is up first, with astronauts stepping on its surface as early as 2025. What the space agency and its partners learn during a few years of lunar exploration will help guide the phases beyond the moon, including sending astronauts to the Red Planet.
“The goal with Artemis is to build off everything we’ve done to this point and really start to establish a presence for humanity beyond low Earth orbit,” says planetary geologist Jacob Bleacher of NASA’s Human Exploration and Operations Mission Directorate in Washington, D.C.
The first big test for Moon to Mars is to show that NASA’s rocket, the Space Launch System, or SLS, which has been in development for over a decade at a cost of more than $20 billion, can successfully launch a crew capsule, without the crew, beyond low Earth orbit.
But that effort has had a rocky start with the Artemis I launch scrubbed twice for fuel leaks and delayed by two hurricanes. Now that it’s off the ground, Artemis I will test the SLS rocket and the Orion advanced crew capsule on a roughly month-long trip beyond the moon and back (SN: 8/26/22). One more test flight, Artemis II, will follow a similar trajectory as the first mission, but with astronauts on board, launching no earlier than 2024.
Artemis III, slated for 2025, is expected to return boots to the moon and make history by landing the first woman on the lunar surface. On that flight, the SLS rocket will launch the Orion crew capsule toward the moon. When it arrives at lunar orbit, it will dock with the human landing system, currently in development by the company SpaceX. Two astronauts will board the SpaceX vehicle, which will bring them to the moon for a 6.5-day stay. That landing system will also bring the astronauts back to Orion, still in lunar orbit, which will then return them to Earth.
If all goes well, NASA plans to run Artemis missions roughly once a year. “We hope to, through those missions that follow Artemis III, build up some infrastructure,” Bleacher says. That infrastructure will include hardware for developing and distributing power on the moon, rovers for the astronauts to traverse long distances and eventually living and working quarters on the surface. The aim is to increase the astronauts’ length of stay from days to perhaps months.
To help support these lunar astronauts, NASA is leading the creation of a new space station. Called the Gateway, it will orbit the moon when complete, maybe by the 2030s. Like the International Space Station, which is scheduled to safely break apart in early 2031, Gateway will be an international and commercial research station. It will also serve as a way station for trips to Mars and beyond.
The moon goddess
NASA astronauts likely won’t be the only people exploring the lunar surface. China aims to land its own astronauts at the moon’s south pole by the next decade. Begun in 2004, China’s lunar exploration program, Chang’e — named after the Chinese goddess of the moon — has seen fast progress. It “is very systematic, very well done, and they’ve been successful every step of the way,” says planetary geologist James Head of Brown University in Providence, R.I.
In 2018, China put a relay communication satellite in orbit around the moon. In 2019, China landed a rover on the lunar farside, providing the first up-close view of the side of the moon hidden from Earth. That rover is still operating. In November 2020, China sent another rover, which brought samples from the moon’s nearside to Earth the following month.
Next up, although China doesn’t share its specific schedule plans, is Chang’e 6, which will collect and return material from the moon’s farside. In 2026, China intends to launch its Chang’e 7 mission to the south pole to search for water ice. “There’s no question,” Head says, “that [China] will be sending humans to the moon toward the end of the decade.”
China’s human-occupied space station, called Tiangong, is now complete and in low Earth orbit. And Mars exploration is on the menu as well. China landed a rover safely there in 2021 and is gearing up for a sample-return mission in the same time frame as a NASA-European Space Agency sample-return mission to Mars.
Science is an international endeavor, but NASA and China’s space agency are unable to collaborate due to the Wolf Amendment (SN: 11/24/18, p. 14). Tacked onto a U.S. appropriations bill in 2011, the amendment prohibits NASA and the White House Office of Science and Technology Policy from collaborating, designing and planning projects with China, unless authorization is granted by the U.S. Congress.
Some lunar scientists, however, hope there can be collaboration between the two nations, such as sharing returned samples. “There are a lot of different places to go in space, and there’s no sense duplicating everything,” Head says.
While human space exploration began as a competition, international collaboration is now the norm. Astronauts from 20 countries have visited the International Space Station over its 22-year history, living together for months and working toward shared interests.
“The International Space Station is a frigging United Nations in orbit in a tin can,” Head says. Private firms also have become increasingly involved in the ISS. And for the Moon to Mars program, international space agencies and private companies are participating, designing and fabricating crucial components.
To the south pole
When humans step on the moon again, they’ll investigate a never-before-explored locale, the moon’s south pole. It’s a region rich with impact craters, uplifted ancient material and water ice (SN: 11/13/09). Both the United States and China are targeting this area to answer new research questions and to access resources humans would need for an extended stay.
This cratered terrain reveals when rocky material tore through the solar system in the first billion years of its history, slamming into the nascent planets (SN: 4/25/12). Earth no longer tells that history, but the moon, without liquid water or a robust atmosphere to smooth away the evidence, retains a surface record of meteorite impacts over billions of years. “Because that record is so perfectly preserved on the lunar surface, it is the single best place in the entire solar system to understand the origin and early evolution of planets,” says planetary scientist David Kring of the Lunar and Planetary Institute in Houston.
And while those are important mysteries, the south pole’s deep craters also hold something thrilling — water ice. There’s a lot to learn about that ice, says lunar exploration scientist Clive Neal of the University of Notre Dame in Indiana. How much is there? Can it be extracted? How to refine it for human use? The Artemis explorers can address those questions, which would enable even longer-term exploration.
That’s the goal this time around: to stay longer for both science exploration and to learn how humans can have a lasting presence on another celestial body. This work “would extend the bounds of human experience in a way that has never happened before,” the Smithsonian’s Muir-Harmony says.
That’s a tall order, considering how NASA’s schedules keep slipping and the cost estimates for each piece of Moon to Mars keep ballooning. A 2021 audit estimates that by the end of 2025, the cost for the Artemis program will reach $93 billion, some $25 billion over NASA estimates.
These next few years of Artemis flights will show what NASA can do. And China’s upcoming missions will show what that nation’s lunar exploration can achieve. The world will be watching both.