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Moon rock

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For other uses, seeMoonrock.

Olivinebasaltcollected from the rim ofHadley Rilleby the crew ofApollo 15

Moon rockorlunar rockis rock originating fromEarth's Moon.This includes lunar material collected during the course of humanexploration of the Moon,and rock that has been ejected naturally from the Moon's surface and landed on Earth asmeteorites.

Sources[edit]

Moon rocks on Earth come from four sources: those collected by sixUnited StatesApollo programcrewed lunar landings from 1969 to 1972; those collected by threeSovietuncrewedLunaprobes in the 1970s; those collected by theChinese Lunar Exploration Program's uncrewed probes; and rocks that were ejected naturally from the lunar surface before falling to Earth aslunar meteorites.

Apollo program[edit]

Six Apollo missions collected 2,200 samples of material weighing 381 kilograms (840 lb),[1]processed into more than 110,000 individually cataloged samples.[2]

Mission Site Sample mass
returned[1] 		Year
Apollo 11 Mare Tranquillitatis

21.55 kg (47.51 lb)

1969
Apollo 12 Ocean of Storms

34.30 kg (75.62 lb)

1969
Apollo 14 Fra Mauro formation

42.80 kg (94.35 lb)

1971
Apollo 15 Hadley-Apennine

76.70 kg (169.10 lb)

1971
Apollo 16 Descartes Highlands

95.20 kg (209.89 lb)

1972
Apollo 17 Taurus-Littrow

110.40 kg (243.40 lb)

1972

Luna program[edit]

Three Luna spacecraft returned with 301 grams (10.6 oz) of samples.[3][4][5]

Mission Site Sample mass
returned 		Year
Luna 16 Mare Fecunditatis 101 g (3.6 oz)[6] 1970
Luna 20 Mare Fecunditatis 30 g (1.1 oz)[7] 1972
Luna 24 Mare Crisium 170 g (6.0 oz)[8] 1976

The Soviet Union abandoned its attempts at acrewed lunar programin the 1970s, but succeeded in landing three roboticLuna spacecraftwith the capability to collect and return small samples to Earth. A combined total of less than half a kilogram of material was returned.

In 1993, three small rock fragments fromLuna 16,weighing 200 mg, were sold forUS$442,500 atSotheby's(equivalent to $933,317 in 2023).[9]In 2018, the same three Luna 16 rock fragments sold forUS$855,000 at Sotheby's.[10]

Chang'e missions[edit]

See also:Changesite–(Y)
Mission Site Sample mass
returned 		Year
Chang'e 5 Mons Rümker 1,731 g (3.8 lb)[11] 2020
Chang'e 6 SouthernApollo crater 1,935.3 g (4.3 lb)[12][13] 2024

In 2020,Chang'e 5,the fifthlunar explorationmission of theChinese Lunar Exploration Program,returned approximately 1,731 g (61.1 oz) of rocks and dust from the Oceanus Procellarum, (the Ocean of Storms), the largest dark region on the Moon, visible on the western edge.[14]The Chang'e-5 samples contain 'perple xing combination' of minerals and include the sixth new lunar mineral, named Changesite-(Y). This phosphate mineral characterized by colorless, transparent columnar crystals.[14]Researchers estimated the peak pressure (11-40 GPa) and impact duration (0.1-1.0 second) of the collision that shaped the sample. Using shock wave models, they estimated the resulting crater to be between 3 to 32 kilometers wide, depending on the impact angle.[15]

The follow-up mission to Chang'e 5,Chang'e 6,reached the Moon on May 8, 2024, and entered lunar orbit for 20 days to find an appropriate landing site.[12]On 1 June, 2024, the lander separated from the orbiter and landed on a mare unit at the southern part of the Apollo crater (36.1°S, 208.3°E).[16]The mission objective was to collect about 2 kg of material from thefar side of the Moonand bring it back to Earth.

The Chang’e-6 probe withstood the high temperatures and collected the samples by drilling into the Moon’s surface and scooping soil and rocks with a mechanical arm, according to a statement from theChina National Space Administration(CNSA). The collected rock was crushed, melted and drawn into filaments about one third of the diameter of a human hair, then spun into thread and woven into cloth. “The lunar surface is rich in basalt and since we’re building a lunar base in the future, we will most likely have to make basalt into fibers and use it as building materials," said engineer Zhou Changyi.[17]

The samples were placed in the ascent vehicle, which docked with the Chang'e 6 orbiter-return vehicle on June 6, 2024[18]China’s Chang’e-6 lunar probe, carrying the first lunar rocks ever collected from the far side of the Moon, landing inChina’s Inner Mongolia regionon June 25, 2024.

Lunar meteorites[edit]

More than 370 lunar meteorites have been collected on Earth,[19]representing more than 30 different meteoritefinds(nofalls), with a total mass of over 1,090 kilograms (2,400 lb).[20]Some were discovered by scientific teams (such asANSMET) searching for meteorites inAntarctica,with most of the remainder discovered by collectors in the desert regions of northernAfricaandOman.A Moon rock known as "NWA 12691", which weighs 13.5 kilograms (30 lb), was found in theSahara Desertat the Algerian and Mauritanian borders in January 2017,[21]and went on sale for $2.5 million in 2020.[22]

Dating[edit]

Rocks from the Moon have been measured byradiometric datingtechniques. They range in age from about 3.16 billion years old for thebasalticsamples derived from thelunar maria,up to about 4.44 billion years old for rocks derived from the highlands.[23]Based on the age-dating technique of "crater counting," the youngest basaltic eruptions are believed to have occurred about 1.2 billion years ago,[24]but scientists do not possess samples of these lavas. In contrast, theoldest ages of rocks from the Earthare between 3.8 and 4.28 billion years.

Composition[edit]

Main article:Geology of the Moon
Common lunar minerals[25]
Mineral Elements Lunar rock appearance
Plagioclasefeldspar Calcium(Ca)
Aluminium(Al)
Silicon(Si)
Oxygen(O) 		White totransparentgray; usually as elongated grains.
Pyroxene Iron(Fe),
Magnesium(Mg)
Calcium(Ca)
Silicon(Si)
Oxygen(O) 		Maroon to black; the grains appear more elongated in the maria and more square in the highlands.
Olivine Iron(Fe)
Magnesium(Mg)
Silicon(Si)
Oxygen(O) 		Greenish color; generally, it appears in a rounded shape.
Ilmenite Iron(Fe),
Titanium(Ti)
Oxygen(O) 		Black, elongated square crystals.

Moon rocks fall into two main categories: those found in the lunar highlands (terrae), and those in themaria.The terrae consist dominantly ofmaficplutonicrocks. Regolithbrecciaswith similarprotolithsare also common. Mare basalts come in three distinct series in direct relation to their titanium content:high-Ti basalts,low-Ti basalts,andVery Low-Ti (VLT) basalts.

Almost all lunar rocks are depleted involatilesand are completely lacking inhydrated mineralscommon in Earth rocks. In some regards, lunar rocks are closely related to Earth's rocks in their isotopic composition of the elementoxygen.The Apollo Moon rocks were collected using a variety of tools, includinghammers,rakes,scoops,tongs,andcore tubes.Most were photographed prior to collection to record the condition in which they were found. They were placed inside sample bags and then aSpecial Environmental Sample Containerfor return to the Earth to protect them from contamination. In contrast to the Earth, large portions of the lunar crust appear to be composed of rocks with high concentrations of the mineralanorthite.The mare basalts have relatively highironvalues. Furthermore, some of the mare basalts have very high levels oftitanium(in the form ofilmenite).[26]

Highlands rocks[edit]

Processing facility in Lunar Sample Building atJSC
Slice of Moon rock at theNational Air and Space MuseuminWashington, DC
Mineral composition of Highland rocks[25]
Plagioclase Pyroxene Olivine Ilmenite
Anorthosite 90% 5% 5% 0%
Norite 60% 35% 5% 0%
Troctolite 60% 5% 35% 0%

Primary igneous rocks in the lunar highlands compose three distinct groups: the ferroan anorthosite suite, the magnesian suite, and the alkali suite.

Lunar breccias, formed largely by the immense basin-forming impacts, are dominantly composed of highlandlithologiesbecause most mare basalts post-date basin formation (and largely fill these impact basins).

  • Theferroan anorthosite suiteconsists almost exclusively of the rockanorthosite(>90% calcic plagioclase) with less commonanorthositicgabbro(70-80% calcic plagioclase, with minor pyroxene). The ferroan anorthosite suite is the most common group in the highlands, and is inferred to represent plagioclase flotationcumulatesof the lunar magma ocean, with interstitial mafic phases formed from trapped interstitial melt or rafted upwards with the more abundant plagioclase framework. The plagioclase is extremely calcic by terrestrial standards, with molar anorthite contents of 94–96% (An94–96). This reflects the extreme depletion of the bulk Moon in alkalis (Na, K) as well as water and other volatile elements. In contrast, the mafic minerals in this suite have low Mg/Fe ratios that are inconsistent with calcic plagioclase compositions. Ferroan anorthosites have been dated using the internal isochron method at circa 4.4 Ga.
  • Themagnesian suite(or "Mg-suite") consists ofdunites(>90% olivine),troctolites(olivine-plagioclase), andgabbros(plagioclase-pyroxene) with relatively high Mg/Fe ratios in the mafic minerals and a range of plagioclase compositions that are still generally calcic (An86–93). These rocks represent later intrusions into the highlands crust (ferroan anorthosite) at round 4.3–4.1 Ga. An interesting aspect of this suite is that analysis of the trace element content of plagioclase and pyroxene requires equilibrium with aKREEP-rich magma, despite the refractory major element contents.
  • Thealkali suiteis so-called because of its high alkali content—for Moon rocks. The alkali suite consists ofalkalianorthositeswith relatively sodic plagioclase (An70–85),norites(plagioclase-orthopyroxene), andgabbronorites(plagioclase-clinopyroxene-orthopyroxene) with similar plagioclase compositions and mafic minerals more iron-rich than the magnesian suite. The trace element content of these minerals also indicates a KREEP-rich parent magma. The alkali suite spans an age range similar to the magnesian suite.
  • Lunar granitesare relatively rare rocks that includediorites,monzodiorites, andgranophyres.They consist of quartz, plagioclase, orthoclase or alkali feldspar, rare mafics (pyroxene), and rare zircon. The alkali feldspar may have unusual compositions unlike any terrestrial feldspar, and they are often Ba-rich. These rocks apparently form by the extremefractional crystallizationof magnesian suite or alkali suite magmas, although liquid immiscibility may also play a role. U-Pb date ofzirconsfrom these rocks and from lunar soils have ages of 4.1–4.4 Ga, more or less the same as the magnesian suite and alkali suite rocks. In the 1960s, NASA researcher John A. O'Keefe and others linked lunar granites with tektites found on Earth although many researchers refuted these claims. According to one study, a portion of lunar sample 12013 has a chemistry that closely resembles javanite tektites found on Earth.[citation needed]
  • Lunar brecciasrange from glassy vitrophyre melt rocks, to glass-rich breccia, to regolith breccias. The vitrophyres are dominantly glassy rocks that represent impact melt sheets that fill large impact structures. They contain few clasts of the target lithology, which is largely melted by the impact. Glassy breccias form from impact melt that exit the crater and entrain large volumes of crushed (but not melted) ejecta. It may contain abundant clasts that reflect the range of lithologies in the target region, sitting in a matrix of mineral fragments plus glass that welds it all together. Some of the clasts in these breccias are pieces of older breccias, documenting a repeated history of impact brecciation, cooling, and impact. Regolith breccias resemble the glassy breccias but have little or no glass (melt) to weld them together. As noted above, the basin-forming impacts responsible for these breccias pre-date almost all mare basalt volcanism, so clasts of mare basalt are very rare. When found, these clasts represent the earliest phase of mare basalt volcanism preserved.

Mare basalts[edit]

Mineral composition of mare basalts[25]
Plagioclase Pyroxene Olivine Ilmenite
Hightitaniumcontent 30% 54% 3% 18%
Lowtitaniumcontent 30% 60% 5% 5%
Very lowtitaniumcontent 35% 55% 8% 2%

Mare basaltsare named as such because they frequently constitute large portions of thelunar maria.These typically contain 18–21 percentFeOby weight, and 1–13 percentTiO2.They are similar to terrestrial basalts, but have many important differences; for example, mare basalts show a large negativeeuropium anomaly.The type location isMare Crisiumsampled byLuna 24.

  • KREEPBasalts(and borderlineVHK (Very High K) basalts) have extraordinary potassium content. These contain 13–16 percentAl2O3,9–15 percent FeO, and are enriched in magnesium and incompatible elements (potassium, phosphorus and rare earth elements) 100–150 times compared to ordinary chondrite meteorites.[27]These are commonly encountered around theOceanus Procellarum,and are identified inremote sensingby their high (about 10 ppm) thorium contents. Most of incompatible elements inKREEPbasalts are incorporated in the grains of the phosphate mineralsapatiteandmerrillite.[28]

Curation and availability[edit]

Genesis Rockreturned by the Apollo 15 mission.

The main repository for the Apollo Moon rocks is theLunar Sample Laboratory Facilityat theLyndon B. Johnson Space CenterinHouston, Texas.For safekeeping, there is also a smaller collection stored atWhite Sands Test FacilityinLas Cruces, New Mexico.Most of the rocks are stored in nitrogen to keep them free of moisture. They are handled only indirectly, using special tools.

Some Moon rocks from the Apollo missions are displayed in museums, and a few allow visitors to touch them. One of these, called theTouch Rock,is displayed in theSmithsonian National Air and Space Museumin Washington, D.C.[29]The idea of having touchable Moon rocks at a museum was suggested by Apollo scientistFarouk El-Baz,who was inspired by his childhoodpilgrimage to Meccawhere he touched theBlack Stone(which inIslamis believed to be sent down from the heavens).[30]

Moon rocks collected during the course of lunar exploration are currently considered priceless.[29]In 2002, a safe was stolen from the Lunar Sample Building that contained minute samples of lunar andMartian material.The samples were recovered, and NASA estimated their value during the ensuing court case at about $1 million for 10 oz (280 g) of material.[citation needed]

Naturally transported Moon rocks in the form of lunar meteorites are sold and traded among private collectors.[citation needed]

Goodwill Moon rocks[edit]

Main article:Lunar sample displays
Honduras plaque

Apollo 17 astronautsEugene CernanandHarrison Schmittpicked up a rock "composed of many fragments, of many sizes, and many shapes, probably from all parts of the Moon". This rock was later labeled sample 70017.[31]President Nixon ordered that fragments of that rock should be distributed in 1973 to all 50 US states and 135 foreign heads of state. The fragments were presented encased in an acrylic sphere, mounted on a wood plaque which included the recipients' flag which had also flown aboard Apollo 17.[32]Many of the presentation Moon rocks are now unaccounted for,having been stolen or lost.

Discoveries[edit]

Three minerals were discovered from the Moon:armalcolite,tranquillityite,andpyroxferroite.Armalcolite was named for the threeastronautson theApollo 11mission:Armstrong,AldrinandCollins.

Stolen and missing Moon rocks[edit]

Main article:Stolen and missing Moon rocks

Because of their rarity on Earth, and the difficulty of obtaining more, Moon rocks have been frequent targets oftheftandvandalism,and many have gone missing or were stolen.

Gallery[edit]

See also[edit]

References[edit]

Citations[edit]

  1. ^abOrloff, Richard W. (September 2004) [First published 2000]."Extravehicular Activity".Apollo by the Numbers: A Statistical Reference.The NASA History Series. Washington, D.C.:NASAHistory Division, Office of Policy and Plans.ISBN978-0-16-050631-4.LCCN00061677.NASA SP-2000-4029.RetrievedAugust 1,2013.
  2. ^"NASA Lunar Sample Laboratory Facility".NASA Curation Lunar.NASA.September 1, 2016.Archivedfrom the original on August 25, 2018.RetrievedOctober 13,2018.
  3. ^Ivankov, A."Luna 16".National Space Science Data Center Catalog.NASA.RetrievedOctober 13,2018.The drill was deployed and penetrated to a depth of 35 cm before encountering hard rock or large fragments of rock. The column of regolith in the drill tube was then transferred to the soil sample container... the hermetically sealed soil sample container, lifted off from the Moon carrying 101 grams of collected material
  4. ^Ivankov, A."Luna 20".National Space Science Data Center Catalog.NASA.RetrievedOctober 13,2018.Luna 20 was launched from the lunar surface on 22 February 1972 carrying 30 grams of collected lunar samples in a sealed capsule
  5. ^Ivankov, A."Luna 24".National Space Science Data Center Catalog.NASA.RetrievedOctober 13,2018.the mission successfully collected 170.1 grams of lunar samples and deposited them into a collection capsule
  6. ^"NASA - NSSDC - Spacecraft - Details".nssdc.gsfc.nasa.gov.RetrievedNovember 8,2015.
  7. ^"NASA - NSSDC - Spacecraft - Details".nssdc.gsfc.nasa.gov.RetrievedNovember 8,2015.
  8. ^"NASA - NSSDC - Spacecraft - Details".nssdc.gsfc.nasa.gov.RetrievedNovember 8,2015.
  9. ^Van Gelder, Lawrence (December 2, 1995)."F.B.I. Revisits Earthly Theft of Moon Rock".The New York Times.RetrievedSeptember 6,2021.
  10. ^"THE ONLY KNOWN DOCUMENTED SAMPLES OF THE MOON AVAILABLE FOR PRIVATE OWNERSHIP".Sothebys.November 29, 2018.
  11. ^"China's Chang'e-5 retrieves 1,731 grams of moon samples".Xinhua News Agency.December 19, 2020.Archivedfrom the original on December 20, 2020.RetrievedDecember 19,2020.
  12. ^ab"NASA - NSSDCA - Spacecraft - Details".nssdc.gsfc.nasa.gov.RetrievedJune 21,2024.
  13. ^"Tân Hoa Xã quyền uy báo tường 丨 Thường Nga số 6 mang về thế giới đầu phân nguyệt bối hàng mẫu 1935.3 khắc"(in Simplified Chinese). Tân hoa võng. June 28, 2024.RetrievedJune 28,2024.
  14. ^abSharmila Kuthunur (February 8, 2024)."China's Chang'e-5 moon samples contain 'perple xing combination' of minerals".Space.RetrievedJune 21,2024.
  15. ^Nielsen, Marissa (February 6, 2024)."Understanding the Moon's History with Chang'e-5 Sample".AIP Publishing LLC.RetrievedJune 21,2024.
  16. ^"First Look: Chang'e 6".lroc.asu.edu.RetrievedJune 21,2024.
  17. ^McCarthy, Nectar Gan, Simone (June 4, 2024)."China's Chang'e-6 probe lifts off with samples from moon's far side in historic first".CNN.RetrievedJune 21,2024.{{cite web}}:CS1 maint: multiple names: authors list (link)
  18. ^"NASA - NSSDCA - Spacecraft - Details".nssdc.gsfc.nasa.gov.RetrievedJune 21,2024.
  19. ^"Meteoritical Bulletin Database — Lunar Meteorite search results".Meteoritical Bulletin Database.The Meteoritical Society. July 10, 2019.RetrievedJuly 20,2019.
  20. ^"List of Lunar Meteorites - Feldspathic to Basaltic Order".meteorites.wustl.edu.RetrievedSeptember 11,2023.
  21. ^"Northwest Africa 12691".The Meteoritical Society.
  22. ^"Super-Rare Moon Meteorite Found In Sahara Desert Goes On Sale For $2.5 Million".Forbes.May 2, 2020.
  23. ^James Papike; Grahm Ryder & Charles Shearer (1998). "Lunar Samples".Reviews in Mineralogy and Geochemistry.36:5.1–5.234.
  24. ^Hiesinger, H.; Head, J. W.; Wolf, U.; Jaumann, R.; Neukum, G. (2003)."Ages and stratigraphy of mare basalts in Oceanus Procellarum, Mare Numbium, Mare Cognitum, and Mare Insularum".J. Geophys. Res.108(E7): 5065.Bibcode:2003JGRE..108.5065H.doi:10.1029/2002JE001985.
  25. ^abc"Exploring the Moon – A Teacher's Guide with Activities, NASA EG-1997-10-116 - Rock ABCs Fact Sheet"(PDF).NASA. November 1997.RetrievedJanuary 19,2014.
  26. ^Bhanoo, Sindya N. (December 28, 2015)."New Type of Rock Is Discovered on Moon".New York Times.RetrievedDecember 29,2015.
  27. ^Wieczorek, Mark; Jolliff, Bradley; Khan, Amir; et al. (2006). "The Constitution and Structure of the Lunar Interior".Reviews in Mineralogy and Geochemistry.60(1): 221–364.Bibcode:2006RvMG...60..221W.doi:10.2138/rmg.2006.60.3.
  28. ^Lucey, Paul; Korotev, Randy; Taylor, Larry; et al. (2006). "understanding the lunar surface and Space-Moon Interactions".Reviews in Mineralogy and Geochemistry.60(1): 100.Bibcode:2006RvMG...60...83L.doi:10.2138/rmg.2006.60.2.
  29. ^abGrossman, Lisa (July 15, 2019)."How NASA has kept Apollo Moon rocks safe from contamination for 50 years".Science News.RetrievedJuly 31,2019.
  30. ^Reichhardt, Tony (June 7, 2019)."Twenty People Who Made Apollo Happen".Air & Space/Smithsonian.Smithsonian Institution.RetrievedSeptember 7,2019.
  31. ^Astromaterials Research & Exploration Science."70017 Ilmenite Basalt"(PDF).NASA.
  32. ^"Where are the Apollo 17 Goodwill Moon Rocks?".Collect Space.

General sources[edit]

External links[edit]

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