Moon rock or lunar rock is rock originating from
Earth's Moon. This includes lunar material collected during the course of human
exploration of the Moon, and rock that has been ejected naturally from the Moon's surface and landed on Earth as
meteorite
A meteorite is a solid piece of debris from an object, such as a comet, asteroid, or meteoroid, that originates in outer space and survives its passage through the atmosphere to reach the surface of a planet or Natural satellite, moon. When the ...
s.
Sources
Moon rocks on Earth come from four sources: those collected by six
United States Apollo program crewed lunar landings from 1969 to 1972; those collected by three
Soviet uncrewed
Luna probes in the 1970s; those collected by the
Chinese Lunar Exploration Program's uncrewed probes; and rocks that were ejected naturally from the lunar surface before falling to Earth as
lunar meteorite
A lunar meteorite is a meteorite that is known to have originated on the Moon. A meteorite hitting the Moon is normally classified as a transient lunar phenomenon.
Discovery
In January 1982, John Schutt, leading an expedition in Antarctica fo ...
s.
Apollo program
Six Apollo missions collected 2,200 samples of material weighing ,
processed into more than 110,000 individually cataloged samples.
Luna program
Three Luna spacecraft returned with of samples.
The Soviet Union abandoned its attempts at a
crewed lunar program in the 1970s, but succeeded in landing three robotic
Luna spacecraft with 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 from
Luna 16, weighing 200 mg, were sold for
US$
The United States dollar (symbol: $; code: USD; also abbreviated US$ or U.S. Dollar, to distinguish it from other dollar-denominated currencies; referred to as the dollar, U.S. dollar, American dollar, or colloquially buck) is the official ...
442,500 at
Sotheby's ().
In 2018, the same three Luna 16 rock fragments sold for
US$
The United States dollar (symbol: $; code: USD; also abbreviated US$ or U.S. Dollar, to distinguish it from other dollar-denominated currencies; referred to as the dollar, U.S. dollar, American dollar, or colloquially buck) is the official ...
855,000 at Sotheby's.
Chang'e
Chang'e 5, the fifth
lunar exploration
The physical exploration of the Moon began when ''Luna 2'', a space probe launched by the Soviet Union, made an impact on the surface of the Moon on September 14, 1959. Prior to that the only available means of exploration had been observation ...
mission of the
Chinese Lunar Exploration Program returned with ~ of samples.
Lunar meteorites
More than 370 lunar meteorites have been collected on Earth,
representing more than 30 different meteorite
finds (no
falls), with a total mass of over . Some were discovered by scientific teams (such as
ANSMET
ANSMET (Antarctic Search for Meteorites) is a program funded by the Office of Polar Programs of the National Science Foundation that looks for meteorites in the Transantarctic Mountains. This geographical area serves as a collection point for mete ...
) searching for meteorites in
Antarctica, with most of the remainder discovered by collectors in the desert regions of northern
Africa and
Oman. A Moon rock known as "NWA 12691", which weighs , was found in the
Sahara Desert at the Algerian and Mauritanian borders in January 2017, and later went on sale for $2.5 million in 2020.
Dating
Rocks from the Moon have been measured by
radiometric dating techniques. They range in age from about 3.16 billion years old for the
basaltic samples derived from the
lunar maria, up to about 4.44 billion years old for rocks derived from the highlands. Based on the age-dating technique of "crater counting," the youngest basaltic eruptions are believed to have occurred about 1.2 billion years ago, but scientists do not possess samples of these lavas. In contrast, the
oldest ages of rocks from the Earth are between 3.8 and 4.28 billion years old.
Composition
Moon rocks fall into two main categories: those found in the lunar highlands (terrae), and those in the
maria. The terrae consist dominantly of
mafic plutonic rocks. Regolith
breccias with similar
protoliths are also common. Mare basalts come in three distinct series in direct relation to their titanium content: ''
high-Ti basalts, low-Ti basalts'', and ''Very Low-Ti (VLT) basalts''.
Almost all lunar rocks are depleted in
volatiles
Volatiles are the group of chemical elements and chemical compounds that can be readily vaporized. In contrast with volatiles, elements and compounds that are not readily vaporized are known as refractory substances.
On planet Earth, the term ' ...
and are completely lacking in
hydrated minerals common in Earth rocks. In some regards, lunar rocks are closely related to Earth's rocks in their isotopic composition of the element
oxygen. The Apollo Moon rocks were collected using a variety of tools, including
hammers,
rakes,
scoops,
tongs, and
core tubes. Most were photographed prior to collection to record the condition in which they were found. They were placed inside sample bags and then a ''Special Environmental Sample Container'' for 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 mineral
anorthite
Anorthite is the calcium endmember of the plagioclase feldspar mineral series. The chemical formula of pure anorthite is Ca Al2 Si2O8. Anorthite is found in mafic igneous rocks. Anorthite is rare on the Earth but abundant on the Moon.
Mineralo ...
. The mare basalts have relatively high
iron values. Furthermore, some of the mare basalts have very high levels of
titanium (in the form of
ilmenite).
Highlands rocks
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 highland
lithologies
The lithology of a rock unit is a description of its physical characteristics visible at outcrop, in hand or core samples, or with low magnification microscopy. Physical characteristics include colour, texture, grain size, and composition. Lit ...
because most mare basalts post-date basin formation (and largely fill these impact basins).
*The ''ferroan anorthosite suite'' consists almost exclusively of the rock ''
anorthosite'' (>90% calcic plagioclase) with less common ''anorthositic
gabbro'' (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 flotation
cumulate
Cumulate rocks are igneous rocks formed by the accumulation of crystals from a magma either by settling or floating. Cumulate rocks are named according to their texture; cumulate texture is diagnostic of the conditions of formation of this group o ...
s of 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.
*The ''magnesian suite'' (or "''mg suite'') consists of ''
dunites'' (>90% olivine), ''
troctolite
Troctolite (from Greek τρώκτης 'trout' and λίθος 'stone') is a mafic intrusive rock type. It consists essentially of major but variable amounts of olivine and calcic plagioclase along with minor pyroxene. It is an olivine-rich anorth ...
s'' (olivine-plagioclase), and ''
gabbros'' (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 a
KREEP-rich magma, despite the refractory major element contents.
*The ''alkali suite'' is so-called because of its high alkali content—for Moon rocks. The alkali suite consists of ''alkali
anorthosites'' with relatively sodic plagioclase (An70–85), ''
norites'' (plagioclase-orthopyroxene), and ''
gabbronorites'' (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 granites'' are relatively rare rocks that include
diorites, monzodiorites, and
granophyres. 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 extreme
fractional crystallization Fractional crystallization may refer to:
* Fractional crystallization (chemistry), a process to separate different solutes from a solution
* Fractional crystallization (geology)
Fractional crystallization, or crystal fractionation, is one of the ...
of magnesian suite or alkali suite magmas, although liquid immiscibility may also play a role. U-Pb date of
zircons from 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.
*''Lunar breccias'' range 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
''Mare basalts'' are named as such because they frequently constitute large portions of the
lunar maria. These typically contain 18–21 percent
FeO
Iron(II) oxide or ferrous oxide is the inorganic compound with the formula FeO. Its mineral form is known as wüstite. One of several iron oxides, it is a black-colored powder that is sometimes confused with rust, the latter of which consists ...
by weight, and 1–13 percent
TiO2. They are similar to terrestrial basalts, but have many important differences; for example, mare basalts show a large negative
europium anomaly. The type location is
Mare Crisium sampled by
Luna 24.
* ''
KREEP Basalts'' (and borderline ''VHK (Very High K) basalts'') have extraordinary potassium content. These contain 13–16 percent
Al2O3, 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. These are commonly encountered around the
Oceanus Procellarum, and are identified in remote sensing by their high (about 10 ppm) thorium contents. Most of incompatible elements in
KREEP basalts are incorporated in the grains of the phosphate minerals
apatite
Apatite is a group of phosphate minerals, usually hydroxyapatite, fluorapatite and chlorapatite, with high concentrations of OH−, F− and Cl− ions, respectively, in the crystal. The formula of the admixture of the three most common e ...
and
merrillite
Merrillite is a calcium phosphate mineral with the chemical formula Ca9NaMg(PO4)7. It is an anhydrous, sodium-rich member of the merrillite ''group'' of minerals.
Mineral species, sub-group and group
Merrillite is a distinct '' mineral species'' ...
.
Curation and availability
The main repository for the Apollo Moon rocks is the
Lunar Sample Laboratory Facility
The Lunar Sample Laboratory Facility (LSLF) is a repository and laboratory facility at NASA's Lyndon B. Johnson Space Center in Houston, Texas, opened in 1979 to house geologic samples returned from the Moon by the Apollo program missions to ...
at the
Lyndon B. Johnson Space Center
The Lyndon B. Johnson Space Center (JSC) is NASA's center for human spaceflight (originally named the Manned Spacecraft Center), where human spaceflight training, research, and flight control are conducted. It was renamed in honor of the late U ...
in
Houston, Texas
Houston (; ) is the most populous city in Texas, the most populous city in the Southern United States, the fourth-most populous city in the United States, and the sixth-most populous city in North America, with a population of 2,304,580 in ...
. For safekeeping, there is also a smaller collection stored at
White Sands Test Facility in
Las 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 the ''Touch Rock'', is displayed in the
Smithsonian National Air and Space Museum in Washington, D.C.
The idea of having touchable Moon rocks at a museum was suggested by Apollo scientist
Farouk El-Baz, who was inspired by his childhood
pilgrimage to Mecca
The Hajj (; ar, حَجّ '; sometimes also spelled Hadj, Hadji or Haj in English) is an annual Islamic pilgrimage to Mecca, Saudi Arabia, the holiest city for Muslims. Hajj is a mandatory religious duty for Muslims that must be carried o ...
where he touched the
Black Stone (which in
Islam
Islam (; ar, ۘالِإسلَام, , ) is an Abrahamic religions, Abrahamic Monotheism#Islam, monotheistic religion centred primarily around the Quran, a religious text considered by Muslims to be the direct word of God in Islam, God (or ...
is believed to be sent down from the heavens).
Moon rocks collected during the course of lunar exploration are currently considered priceless.
In 2002, a safe was stolen from the Lunar Sample Building that contained minute samples of lunar and
Martian material. The samples were recovered, and NASA estimated their value during the ensuing court case at about $1 million for of material.
Naturally transported Moon rocks in the form of lunar meteorites are sold and traded among private collectors.
Goodwill Moon rocks
Apollo 17 astronauts
Eugene Cernan and
Harrison Schmitt picked 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. 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.
Many of the presentation Moon rocks are now unaccounted for,
having been stolen or lost.
Discoveries
Three minerals were discovered from the Moon:
armalcolite
Armalcolite () is a titanium-rich mineral with the chemical formula (Mg,Fe2+)Ti2O5. It was first found at Tranquility Base on the Moon in 1969 during the Apollo 11 mission, and is named for ''Arm''strong, ''Al''drin and ''Col''lins, the three ...
,
tranquillityite
Tranquillityite is silicate mineral with formula (Fe2+)8Ti3Zr2 Si3O24. It is mostly composed of iron, oxygen, silicon, zirconium and titanium with smaller fractions of yttrium and calcium. It is named after the Mare Tranquillitatis (Sea of Tranqui ...
, and
pyroxferroite
Pyroxferroite (Fe2+,Ca)SiO3 is a single chain inosilicate. It is mostly composed of iron, silicon and oxygen, with smaller fractions of calcium and several other metals. Together with armalcolite and tranquillityite, it is one of the three minera ...
. Armalcolite was named for the three
astronaut
An astronaut (from the Ancient Greek (), meaning 'star', and (), meaning 'sailor') is a person trained, equipped, and deployed by a human spaceflight program to serve as a commander or crew member aboard a spacecraft. Although generally r ...
s on the
Apollo 11 mission:
Armstrong,
Aldrin and
Collins.
Stolen and missing Moon rocks
Because of their rarity on Earth, and the difficulty of obtaining more, Moon rocks have been frequent targets of
theft and
vandalism, and many have gone missing or were stolen.
Gallery
File:MoonTouch.jpg, A visitor touching a lunar sample at the Kennedy Space Center Visitor Complex
File:NASA Lunar Sample 15555.jpg, NASA Lunar sample 15555 on display at Space Center Houston Lunar Samples Vault, at NASA's Johnson Space Center
The Lyndon B. Johnson Space Center (JSC) is NASA's center for human spaceflight (originally named the Manned Spacecraft Center), where human spaceflight training, research, and flight control are conducted. It was renamed in honor of the late U ...
File:NASA Lunar Sample 15498.jpg, NASA Lunar sample 15498 on display at Space Center Houston Lunar Samples Vault, at NASA's Johnson Space Center
The Lyndon B. Johnson Space Center (JSC) is NASA's center for human spaceflight (originally named the Manned Spacecraft Center), where human spaceflight training, research, and flight control are conducted. It was renamed in honor of the late U ...
File:NASA Lunar Sample 60015.jpg, NASA Lunar sample 60015 on display at Space Center Houston Lunar Samples Vault, at NASA's Johnson Space Center
The Lyndon B. Johnson Space Center (JSC) is NASA's center for human spaceflight (originally named the Manned Spacecraft Center), where human spaceflight training, research, and flight control are conducted. It was renamed in honor of the late U ...
File:NASA Lunar Sample 60016.jpg, NASA Lunar sample 60016 on display at Space Center Houston Lunar Samples Vault, at NASA's Johnson Space Center
The Lyndon B. Johnson Space Center (JSC) is NASA's center for human spaceflight (originally named the Manned Spacecraft Center), where human spaceflight training, research, and flight control are conducted. It was renamed in honor of the late U ...
File:NASA Lunar Sample Return Container.jpg, NASA Lunar Sample Return Container with Lunar soil on display at Space Center Houston Lunar Samples Vault, at NASA's Johnson Space Center
The Lyndon B. Johnson Space Center (JSC) is NASA's center for human spaceflight (originally named the Manned Spacecraft Center), where human spaceflight training, research, and flight control are conducted. It was renamed in honor of the late U ...
File:Lunar Ferroan Anorthosite (60025).jpg, Lunar
Lunar most commonly means "of or relating to the Moon".
Lunar may also refer to:
Arts and entertainment
* ''Lunar'' (series), a series of video games
* "Lunar" (song), by David Guetta
* "Lunar", a song by Priestess from the 2009 album ''Prior t ...
Ferroan Anorthosite #60025 ( Plagioclase Feldspar). Collected by Apollo 16
Apollo 16 (April 1627, 1972) was the tenth crewed mission in the United States Apollo space program, administered by NASA, and the fifth and penultimate to land on the Moon. It was the second of Apollo's " J missions", with an extended sta ...
from the Lunar Highlands near Descartes Crater. This sample is currently on display at the National Museum of Natural History in Washington, DC
File:Lunar Sample Processing Facility NASA JSC DSCN0199.JPG, Samples in Lunar Sample Building at JSC
JSC may refer to:
* Jane Street Capital, a global proprietary trading firm
* Johnson State College, one of the Vermont State Colleges, and located at Johnson, Vermont, United States
* Jeffree Star Cosmetics, an American cosmetics franchise
* Joi ...
File:SaturnVcenterPieceOfMoon.JPG, Moon rock on display for visitors to touch at the Apollo/Saturn V Center
The Kennedy Space Center Visitor Complex is the visitor center at NASA's Kennedy Space Center on Merritt Island, Florida
Merritt Island is a peninsula, commonly referred to as an island, in Brevard County, Florida, United States, located o ...
File:Moon sample case in National Museum of Natural History.jpg, Sample collection case, containing collection bags for use on the surface, at the National Museum of Natural History
File:Moon tongs in National Museum of Natural History.jpg, Tongs used to pick up Moon rocks
File:Moon Regolith in Moscow.JPG, A piece of regolith from Apollo 11 presented to the Soviet Union and exhibited in the Memorial Museum of Cosmonautics in Moscow.
File:Apollo 17, Goodwill Moon Rock, close-up.jpg, Apollo 17 "Goodwill Moonrock"
File:Mondgestein Apollo 17 02-RZ.jpg, Cut fragment of Apollo 17 sample 76015, an impact melt breccia
File:Lunar sample 15016 S71-45477.jpg, Sample 15016, the Seatbelt basalt
Lunar Sample 15016, better known as the "Seatbelt Basalt", is a Moon rock, lunar sample discovered and collected on the Apollo 15 mission in 1971 in the Hadley-Apennine region of the Moon. The rock is a vesicular olivine basalt.
It is so named ...
File:Lunar Sample 61016 - Big Muley.jpg, Apollo 16's sample 61016, better known as Big Muley, is the largest sample collected during the Apollo program
File:Big Bertha sample 14321.jpg, Big Bertha, collected on Apollo 14
Apollo 14 (January 31, 1971February 9, 1971) was the eighth crewed mission in the United States Apollo program, the third to land on the Moon, and the first to land in the lunar highlands. It was the last of the " H missions", landings at s ...
, is among the largest rock samples returned from the Moon (nearly 9 kilograms)
File:Moon rocks on display at the National Museum of China.jpg, Moon rocks on display at the National Museum of China
See also
*
Sample-return mission
A sample-return mission is a spacecraft mission to collect and return samples from an extraterrestrial location to Earth for analysis. Sample-return missions may bring back merely atoms and molecules or a deposit of complex compounds such as lo ...
*
Bench Crater meteorite
The Bench Crater meteorite is a meteorite discovered on the Moon by Apollo 12 astronauts in 1969. It is part of the friable basalt lunar sample 12037. Found on the north-west rim of the Bench Crater, it is the first meteorite to be discovered on a ...
*
Geology of the Moon
*
Hadley Rille meteorite
*
Helium-3
Helium-3 (3He see also helion) is a light, stable isotope of helium with two protons and one neutron (the most common isotope, helium-4, having two protons and two neutrons in contrast). Other than protium (ordinary hydrogen), helium-3 is the ...
*
List of Apollo lunar sample displays
*
Lunar ice
*
Lunar Receiving Laboratory
The Lunar Receiving Laboratory (LRL) was a facility at NASA's Lyndon B. Johnson Space Center (Building 37) that was constructed to quarantine astronauts and material brought back from the Moon during the Apollo program to reduce the risk of ...
*
Lunar regolith simulant
A lunar regolith simulant is a terrestrial material synthesized in order to approximate the chemical, mechanical, or engineering properties of, and the mineralogy and particle size distributions of, lunar regolith. Lunar regolith simulants are use ...
*
Lunar resources
*
Lunar soil
References
Citations
General sources
*
* Paul D. Spudis, ''The Once and Future Moon'', Smithsonian Institution Press, 1996, .
External links
Rocks & Soils from the MoonJohnson Space Center
—Washington University, Department of Earth and Planetary Sciences
Lunar SamplesLunar and Planetary Institute
educational journal
collectSPACE
collectSPACE
* Kentucky's lunar sample displays in the Kentucky Historical Society objects catalog
Apollo 11Apollo 17
{{DEFAULTSORT:Moon Rock
Apollo program
Extraterrestrial rocks
Igneous rocks
Lunar science
Petrology