A camera was rolling as Neil Armstrong and Buzz Aldrin climbed down from the Eagle lunar lander, becoming the first two humans to set foot on the moon. As he backed out of the module, Armstrong pulled a lever to deploy the device, which had been stored in a bay in the spacecraft, and it began to transmit a broadcast to a record-setting 650 million viewers around the Earth.
Armstrong then removed the camera and set it up on a tripod, capturing the two men’s actions on a live, global television spectacle on July 20, 1969. Around the planet, people stopped whatever they were doing to watch history being made, and that television camera “enabled people to get a sense of personal connection and participation and witness the event in real time,” says Teasel Muir-Harmony, curator of the Apollo collection at the National Air and Space Museum. The camera, as an artifact, demonstrates that “one of the important parts of the Apollo program was not just the activity that was happening on the lunar surface, but it was also the global audience back on Earth following the flight.”
But when the men went back into the Eagle, they left the camera behind. The object remains on the moon today.
That camera isn’t alone. Apollo astronauts “had to limit the amount of material they were bringing back on the spacecraft with them,” Muir-Harmony says. To make it off the moon’s surface and rejoin the command module in orbit, they needed to keep their spacecraft light to conserve fuel and make space for heavy samples of lunar rocks. It was an exact science. “They even had a scale to help weigh material,” she says.
As a result, each of the six lunar landing sites from NASA’s Apollo program contains an assortment of discarded items. The later missions left behind battery-powered, four-wheeled rovers roughly the size of a Volkswagen Beetle that could shuttle astronauts around the moon. Other missions abandoned various tools, from tongs to rakes. On Apollo 14, astronaut Alan Shepard hit two golf balls out into the moonscape that were never retrieved.
These items are part of the breadcrumb trail that tells the story of humans in space. Lots of objects did come back to Earth, and many of them now reside in museums. But the artifacts left behind also tell stories about the Apollo program, as well as about uncrewed, robotic missions by the United States and other countries.
“Our history … is the most valuable and most vulnerable resource we have on the moon right now,” says Michelle Hanlon, co-founder and CEO of For All Moonkind, a nonprofit dedicated to protecting lunar landing sites. Beyond these known objects, any traces of the astronauts that have yet to be discovered, such as the possibility they carved their initials into the regolith, “tell us a lot about humanity,” she adds.
In one sense, the moon is an ideal place to preserve artifacts. With no wind and no flowing water, delicate landscape features such as the footprints of astronauts appear to have remained intact. But in another sense, objects on the moon are prone to damage. Micrometeoroids could pelt and dent metals, for example, and solar radiation can bleach textiles or photographs.
However, as human activity ramps up on the lunar surface—with more than 100 missions planned to occur by 2030—it poses another looming threat to these items. For example, individuals might go to the moon, retrieve artifacts and sell them illegally. Given the significance of the Apollo historic sites, they could become the targets of politically motivated aggression, Muir-Harmony says. Or, if tourists one day travel to the moon to explore lunar history, these futuristic vacationers could walk on top of the historic footprints. It also remains possible that a spacecraft might inadvertently destroy some of the lunar artifacts, perhaps by landing too close to the historic sites.
“We are on this unique threshold,” Hanlon says. With missions planned in the near future, nations and industry actors can choose to consider space history as they approach these flights, rather than trying to salvage it after the fact, she adds. “We have an opportunity to actually act proactively.”
For the time being, a lot of these upcoming missions are focused on the lunar south pole, rather than around the equator where the Apollo missions landed. But this might not always be the case. Nations worldwide have acknowledged the importance of protecting historic lunar sites, or “outer space heritage,” in the Artemis Accords, which have been signed by 43 countries so far. The accords are a non-legally binding set of statements that outline best practices for safe exploration of the moon and, eventually, Mars and beyond. While the agreement lays out common guiding principles for exploration, it stops short of providing specific guidelines for how to safeguard historic places.
“Understanding how to approach them and to preserve them, I think, needs an eye toward understanding how they’re part of global history, and really treating them as not just national historic sites, but international historic sites,” Muir-Harmony says. “They’re an important part of American history, but they’re even more than that. They’re an important part of the history of humanity.”
Some of the items left behind are highly intentional and sentimental, including a Bible and a photo of astronaut Charles Duke’s family. And others—such as vomit bags, facial wipes, nail clippers and earplugs—are less glamorous. But across the surface of the moon, these motley artifacts contain clues to a history of courage, ingenuity, exploration and unprecedented achievement.
This weekend will mark the 55th anniversary of the first human lunar landing. Since then, humans walked on the moon five more times, ending with Apollo 17 in 1972. No one has set foot on the moon since.
Now, NASA plans to again land astronauts on the lunar surface within the next few years on its Artemis 3 flight. As space agencies and private companies look ahead at future exploration, here are the stories of some of the Apollo program artifacts on the moon that represent our space heritage.
American flags
NASA’s Apollo missions were American achievements that took place in a time of heightened geopolitical tensions. But they were, more broadly, human achievements—and as the Apollo 11 crew prepared for their mission, officials aimed to toe the line between symbolically depicting the effort as both of these things.
“It was very contested at the time, about whether or not the U.S. should raise a flag on the moon,” Muir-Harmony says.
The United Nations’ Outer Space Treaty of 1967 forbade countries from establishing territory on the moon, and some people were concerned that raising a flag would look like Americans were staking a claim. But on the other side, especially among members of Congress, people argued that the American public needed to see a flag to symbolize how it was a U.S. program.
“Until shortly before the mission, it was undecided,” Muir-Harmony says. “But with the pressure of Congress, it was decided to raise a flag on the moon.”
Beyond the political implications, these artifacts can tell a story of what it’s like to exist in the lunar environment for up to 55 years. “It’s believed by scientists that today, those flags are bleached white—so they’re no longer the red, white and blue stripes that we think of when we think of an American flag—because of the harsh environment on the lunar surface,” Muir-Harmony says.
“The materials are pretty weak, because they were just sort of off-the-shelf flags that they adopted for moon use. So, they’re not some special material,” says Lisa Young, an objects conservator at the National Air and Space Museum. “They’re like a typical nylon outdoor flag. So, if you think of something that’s outside your house for a long time in the sun, you know, it’s going to start to shred or discolor.”
NASA’s Lunar Reconnaissance Orbiter, which circles the moon, has photographed each of the Apollo landing sites, revealing that the flags are still intact. Only one flag, the one planted during Apollo 11, appears to have fallen over—which matches a report from Aldrin that exhaust from the lunar module’s engine knocked down the flag as he and Armstrong lifted off from the moon.
Astronauts’ moon shoes and gloves
Armstrong’s lunar spacesuit is on display at the National Air and Space Museum. But it’s missing a key component: the lunar overshoes. These bulky pieces of footwear slid over the astronauts’ spacesuits to protect them during moonwalks. The overshoes’ soles featured horizontal lines, which are seen in the footprints in the regolith. Armstrong, Aldrin and many other Apollo astronauts shed their boots and left them behind when returning home.
Some, however, have been brought back. Apollo 17 astronauts Gene Cernan and Harrison Schmitt—the last people to walk on the moon—returned their overshoes to Earth and even collected other items from their 1972 mission, such as a repaired fender, that could preserve the history of their flight. Knowing that Apollo 17 was the last lunar landing planned for a long time, “they made a calculation in their mind about … that historic weight in relationship to the actual physical weight and the issues that that might cause for the flight home,” Muir-Harmony says.
The pair of astronauts did leave their gloves behind, however. To Young, parts of astronauts’ spacesuits are the most fascinating artifacts. Sized for each individual and involved in how astronauts carried out their work, “they represent the most human side of the mission,” she says.
Science experiments and human waste
After accomplishing the first human moon landing, Aldrin carried a white piece of equipment roughly the size of a large suitcase and set it up on the ground. Called a laser ranging retroreflector, it helps measure the distance between the Earth and the moon. The crews of Apollo 14 and Apollo 15 also deployed similar equipment.
The reflector is still functioning today—and it’s the only science project from the Apollo program with that distinction. “That’s in large part because it’s very passive on the lunar surface,” Muir-Harmony says. The hardware is just a reflector, and lasers beamed from Earth keep it operational.
Continued work with the reflector monitors how the distance to the moon is changing, adds Muir-Harmony, “not just because of its orbit, but also because it’s slowly receding from the Earth over time.”
Astronauts deployed other science hardware on the moon that remains there to this day, from seismic experiments to magnetic field detectors to solar wind measuring devices and other sensors. Looking at these items now could reveal how well they have weathered lunar hazards.
Another object of scientific interest? Literal human waste. Astronauts left behind containers of urine and feces, since these were expendable, compared with lunar rock samples. But now, if able to retrieve this material, some scientists want to explore whether bacteria has been able to survive in it—taking advantage of a unique opportunity to study how life reacts to the lunar environment.
“There’s so much we can learn from accessing those sites in a responsible manner,” Hanlon says.
Hammer and feather
Reaching the moon was an engineering success in its own right, but Apollo astronauts also capitalized on the opportunity to test scientific ideas. During the Apollo 15 mission in 1971, astronauts David Scott and James Irwin decided to test a centuries-old proposition about gravity from the Italian mathematician Galileo Galilei.
“I guess one of the reasons we got here today was because of a gentleman named Galileo, a long time ago, who made a rather significant discovery about falling objects in gravity fields,” Scott said in a broadcast while on the moon.
Galileo proposed that any two objects, regardless of their mass, would fall at the same rate if there were no air resistance. “And we thought, ‘Where would be a better place to confirm his findings than on the moon?’” Scott said. Since it has almost no atmosphere, the moon is considered to be in an airless vacuum.
With a hammer in his right hand and a falcon feather in his left, Scott dropped both items in unison. They both fell and hit the regolith at the same time. “How about that?” Scott and Irwin each said on the broadcast.
Having served their purpose, both the hammer and the feather were left on the moon. Now, the items serve as a reminder of that moment, Hanlon says, when “history comes full circle” and the astronauts were “able to prove the theory of a scientist, Galileo, who never reached the stars himself.”
Symbolic tributes
Affixed to the ladder that Armstrong and Aldrin climbed down to reach the moon is a commemorative plaque denoting the mission’s significance to human history. “Here men from the planet Earth first set foot upon the moon July 1969 A.D.,” reads the inscription. “We came in peace for all mankind.”
The panel, which is still affixed to the lunar module’s descent stage on the moon’s surface, includes two depictions of Earth, capturing its Western and Eastern Hemispheres. “A lot of work went into the symbolism of this plaque,” Muir-Harmony says. “They wanted to show Earth as it looks from outer space, with no political boundaries. And that was seen as really important to signal that message that this was a mission that was broader than the United States, that this was for all humankind.”
Other gestures also symbolized the international significance of that lunar landing. Leaders from more than 70 nations wrote messages of goodwill, which were then photographed and shrunk down more than 200 times. The final product—a silicon disk roughly the size of a U.S. half dollar coin—is legible with a microscope and was placed on the moon by the Apollo 11 astronauts. They also left a gold replica of an olive branch, a symbol for peace.
Armstrong and Aldrin laid down an Apollo 1 mission patch on the lunar surface in tribute to the crew members Gus Grissom, Edward White and Roger Chaffee, who died in a command module fire on the launch pad in 1967.
But the astronauts didn’t stop at honoring Americans who had died in the space program. Frank Borman, who orbited the moon as commander of Apollo 8, was invited to meet with officials in the Soviet Union during the space race. This meeting “was really unprecedented,” Muir-Harmony says.
Borman asked whether there were any objects American astronauts could bring to the moon to recognize the cosmonauts who had died. He received two commemorative medallions for Vladimir Komarov, who died in a crash landing of the Soyuz 1 spacecraft, and Yuri Gagarin, the first human in space who later died in a plane crash in 1968. The Apollo 11 astronauts also carried these to the moon.
“When you think about the height of the Cold War, and the competition, and the idea that sending humans to the moon and landing there was in large part in competition with the Soviet Union, to then symbolically connect that story and to include something from the Soviet Union, I think, is quite powerful,” Muir-Harmony says.