Moon Rocks and Samples

The whole inventory is smaller than you might expect. Six Apollo landings between July 1969 and December 1972 returned 382 kilograms of rock, core, pebbles, sand and dust, about 2,200 separate specimens from six sites. Three Soviet robots returned a few hundred grams between 1970 and 1976. China's Chang'e 5 and Chang'e 6 added just under 3.7 kilograms in 2020 and 2024. That is eleven missions and roughly 386 kilograms in total, and because samples are cut, lent, analysed and sometimes used up, the collection scientists actually work with is counted in numbered pieces: NASA's 382 kilograms has been divided into more than 110,000 catalogued samples.

The Apollo numbers grew mission by mission. NASA's Lunar Meteorite Compendium, quoting the Lunar Sourcebook, gives 21.5 kg for Apollo 11, 34.4 for Apollo 12, 42.3 for Apollo 14, 77.3 for Apollo 15, 95.7 for Apollo 16 and 110.5 for Apollo 17, 381.7 kg in all. NASA's curation pages round that to 382 kg, and an older NSSDCA summary says almost 400. None of these is wrong. They are the same haul counted to different precision, and it is worth knowing which one you are reading before comparing it with anything else. The weight is also not all rock. Only about 265 kg of the collection is pieces larger than a centimetre; the remaining 117 kg is fine material, almost all of it soil, according to Lunar Sourcebook figures quoted by the meteorite scientist Randy Korotev.

The Soviet Union did it with robots. Luna 16 landed in the Sea of Fertility, Mare Fecunditatis, on 20 September 1970, drilled 35 centimetres into the surface and sealed 101 grams of soil in its return capsule, which reached Earth on 24 September. The container went to the Vernadsky Institute of Geochemistry and Analytical Chemistry (GEOKHI) in Moscow, which a Gagarin Museum article described in 2023 as the country's largest store of extraterrestrial material, soil from all three successful Luna missions included. Luna 20 brought back highland soil from near Amegino crater in February 1972, and Luna 24 returned in August 1976 from Mare Crisium with a core from about two metres down. Its drill went 225 centimetres into the regolith at a slant, but the core that came home was 160 centimetres long, a small lesson in the gap between what a mission does and what it returns. Between these successes came two failures, Luna 18 and Luna 23: Luna 18 crashed in September 1971, and Luna 23 was damaged on landing in 1974 and could not collect its sample.

The Soviet totals are where announced and recorded masses part company. Russian accounts, such as the Gagarin Museum's, give 101, 55 and 170 grams and a total of 326. NASA's curation pages say the three missions returned 300 grams, a Chinese news report on the day Chang'e 5's samples were handed over said about 301 grams, and NASA's NSSDCA catalogue lists Luna 20 at 30 grams. Almost the whole disagreement is Luna 20. Russian sources carry 55 grams; the description of the core quoted in NASA's Lunar Sample Compendium says it weighed 50 grams; NSSDCA's 30 grams, added to 101 and 170, matches the 301 gram total. No published reconciliation turned up in the sources checked for this page, so the honest answer is a range with its origins attached. For Luna 24 the figures agree to within a gram: 170.1 in NSSDCA's catalogue, 170 in Russian sources and in the Compendium.

China's two announcements differ by one revealing word. Chang'e 5 landed in Inner Mongolia early on 17 December 2020, Beijing time, and when its container was handed over two days later the announcement said that by preliminary measurement (经初步测量) the mission had collected about 1,731 grams. The target had been two kilograms. Hu Hao, chief designer of the programme's third phase, later said the haul fell short for various reasons, and pointed out the happy accident that 17-3-1 matched the programme's 17 years, three steps and one success. When Chang'e 6 came home from the far side on 25 June 2024, CNSA's Chinese statement of 28 June dropped the word preliminary: by measurement (经测量), 1,935.3 grams. Xinhua's English report of the same announcement kept it. Neither figure had been revised in any CNSA statement found for this page as of September 2026, and in mid-2024 an article on CNSA's website still gave the Chang'e 5 haul as 1,731 grams. Chang'e 6's material came from the South Pole-Aitken basin; the same article counted ten earlier sample returns, all from the near side.

The largest lunar collection on Earth was not brought back by anyone. Lunar meteorites are pieces blasted off the Moon by impacts that later fell to Earth. The first rock recognised as one, Allan Hills A81005, was picked up in Antarctica on 18 January 1982, nine years after the last Apollo landing. Japanese teams had already collected lunar meteorites in the Yamato Mountains, among them Yamato 791197 on 20 November 1979, but their origin was only recognised in 1984. Korotev's list, updated on 11 September 2026, counts 832 approved names with a combined mass of 2,036 kilograms, 5.3 times the Apollo total. That headline needs a warning. Many names are fragments of one meteoroid found separately, and Korotev himself writes that once confirmed or strongly suspected pairs are counted together, the number of actual meteoroids falls to less than half the number of named stones. NASA's Lunar Meteorite Compendium, which groups such pairs, listed nearly 150 unique lunar meteorites as of January 2024 and gave the combined mass of all lunar meteorites as 417 kilograms, although Korotev's running total had already passed 1,000 kilograms in November 2022. The two tallies use different rules and dates, give very different masses, and neither is an official census.

A meteorite also arrives without an address. Its chemistry can hint at a region, as with the lunar meteorite found in the Yamato Mountains in 1986 that Japan's National Institute of Polar Research (NIPR) displays at its science museum in Tachikawa: a piece of highland crust about 4.4 billion years old that the institute thinks came from the far side, because it is poor in the iron and thorium that the near side is rich in. The institute holds about 17,400 Antarctic meteorites in all, and provides samples to researchers free of charge. Where lunar meteorites turn up says more about deserts than about the Moon. By Korotev's count about 85 per cent have been found in northern Africa, mostly by local people and collectors, while all the Antarctic finds together weigh only 5.7 kilograms. Unlike Apollo rock, lunar meteorites are bought and sold openly, at roughly 20 to 4,000 dollars a gram by Korotev's figures, and he warns that some online listings are ordinary Earth rock.

The Apollo collection lives in Building 31N at NASA's Johnson Space Center in Houston, built between 1977 and 1979 for the purpose. Pristine samples, those that have never left NASA custody, sit in stainless steel cabinets purged with high-purity nitrogen and are always separated from human hands by three layers of gloves. The vaults stand above expected hurricane storm-surge heights, and even the floor coverings, plumbing and paint were screened for elements that could contaminate the rocks. Material that goes out to a laboratory and comes back is reclassified as returned and kept apart. China's rules, issued in January 2021, name a main store, the National Astronomical Observatories of the Chinese Academy of Sciences in Beijing, and a backup store; when Chang'e 5's samples were handed over, an off-site backup was reported to be planned for Shaoshan in Hunan, Mao Zedong's birthplace. The rules divide every haul into four classes: permanent storage, backup permanent storage, research, and public-benefit use such as exhibitions. Chang'e 5's designers kept the sealed sample container between minus 25 and 55 C even through re-entry, and on the ground it was stored and opened under nitrogen, much as NASA handles its pristine Apollo samples.

Scientific samples are lent, and the paperwork is the price. At NASA a researcher needs favourable peer review, either a recommended proposal or published papers in the field, and a written request naming the samples, the quantities and the planned use. The Apollo sample curator decides whether outside review is needed; if it is, the request goes to the Astromaterials Allocation Review Board, which NASA's page says was formerly CAPTEM. The institution then signs a loan agreement with a security plan. Less than 10 grams can travel to a US laboratory by registered mail, foreign shipments go by diplomatic pouch to the nearest American embassy, and anything over 10 grams must be carried by hand. NASA's own pages put the traffic at several hundred samples a year (one says nearly 400, another about 500). China runs a parallel system and publishes the lists. Its first allocation, on 12 July 2021, sent 31 Chang'e 5 samples totalling 17,476.4 milligrams to 13 institutions. By June 2024 it had lent more than 80 grams in seven batches to over 100 Chinese teams, about 5 per cent of the Chang'e 5 haul. Chang'e 6 material has since joined the lists: an allocation announced on 5 February 2026 approved 22,836.6 milligrams from both missions for 14 institutions, and on 8 May 2026 CNSA opened another round of applications for both, which closed on 8 June.

Samples have also been diplomacy. In March 1973 NASA handed Soviet representatives three grams each of Apollo 16 and Apollo 17 material and received samples from Luna 16 and Luna 20 in return (the Lunar Sample Compendium's inventory shows Luna 16 material already received in the United States in July 1971); the Luna 20 portion allocated to NASA weighed 2.036 grams, according to the certificate quoted in the Compendium. Luna 24 material went to the United States, Britain, India and other countries. In 1978 Zbigniew Brzezinski, President Carter's national security adviser, brought China a one gram fragment cast in acrylic, and the Americans said nothing about where or when it had been collected. The Chinese Academy of Sciences passed it to the cosmochemist Ouyang Ziyuan, later the first chief scientist for lunar application science in China's lunar exploration programme. He cut it in two and kept one half. Analyses used up the other, produced 14 papers and let Chinese scientists deduce that it came from Apollo 17, then, with the help of published American data, which numbered sample it was. It is a high-titanium mare basalt from the Apollo 17 landing area on the southeastern edge of Mare Serenitatis, and the half gram that was kept is on show at the Beijing Planetarium. Forty-seven years later the flow reversed. In April 2025 China accepted applications to borrow Chang'e 5 samples from abroad, including two from American universities, and on 24 April 2026 it approved a second international round for France's IRAP, the University of Manchester and the space institute of Turkey's TÜBİTAK. The Chinese and English notices disagree on what the Turkish institute receives, four powders and one rock clast in Chinese and the reverse in English, a small reminder to read the original.

The most famous gifts were political. In 1970 and 1973 President Richard Nixon presented lunar samples to 135 countries and the 50 US states; the second set came from sample 70017, which NASA's history office calls the Goodwill Rock and describes as the last rock Eugene Cernan and Harrison Schmitt collected (the Lunar Sample Compendium says one of the last). These were gifts to governments, and NASA leaves them off its own list of lunar displays. Many have since gone missing. An AFP tally in 2019, built on research by the retired NASA special agent Joseph Gutheinz, his students and the space history site collectSPACE, found both of Afghanistan's and both of Libya's missing; Malta's Apollo 17 piece stolen from a museum in May 2004 and still missing at the time of the tally; Ireland's Apollo 11 display lost when a 1977 fire destroyed Dunsink Observatory, with the debris ending up in a landfill at Finglas; and Honduras's Apollo 17 fragment sold by an army colonel to a Florida businessman for 50,000 dollars. The businessman offered it to undercover agents for 5 million in a 1998 sting called Operation Lunar Eclipse, and the rock was seized and returned to Honduras.

NASA has been robbed from the inside too. In the spring of 2002 three NASA interns used their badges to enter Johnson Space Center at night and remove a 600 pound safe holding samples from every Apollo mission, along with a piece of a Martian meteorite. They offered the samples on the website of a mineral club in Antwerp; a Belgian collector alerted the FBI, and agents posing as his relatives arrested them at a restaurant in Orlando on 20 July 2002, the 33rd anniversary of the first landing. The samples were recovered, but the FBI said they had been contaminated to the point of being nearly useless for science, and that three decades of a scientist's handwritten notes kept in the safe were destroyed. The ringleader, Thad Roberts, was sentenced to more than eight years in prison. A NASA Inspector General audit in December 2011 counted 517 loaned astromaterial samples lost or stolen between 1970 and June 2010, including 218 from that single theft and a lunar sample disk lent to an observatory in Delaware in 1978 that still had not been found when the audit was published.

Some of the Moon was kept closed on purpose. In December 1972 Cernan and Schmitt hammered a double drive tube into a landslide deposit in the Taurus-Littrow valley. The lower half, 73001, was sealed under vacuum on the Moon and later stored inside a second vacuum tube in a nitrogen cabinet; the upper half, 73002, came home in an ordinary container. Both waited for the Apollo Next Generation Sample Analysis programme, ANGSA, which opened 73002 in 2019. For 73001, curators first CT-scanned the tube at the University of Texas at Austin, then in February 2022 captured the gas inside, and on 21 and 22 March 2022 pushed the core out and began dividing it into half-centimetre slices. "We are the first people who got to actually see this soil for the first time," said the deputy curator, Juliane Gross. NASA describes it as one of the last few samples it had kept unopened, and its curator of astromaterials, Francis McCubbin, gave the reason: the samples were curated for the long term so that scientists fifty years in the future could analyse them.

What ties these stories together is scarcity. Chinese allocations are published in milligrams, NASA sends out a few hundred samples a year from a collection curated for scientists half a century ahead, and an announced mass, once printed, tends to become the number everyone repeats. When you meet a figure for Moon samples, the useful questions are the ones this page has tried to answer: counted by whom, measured when, and rounded how.