Moon rock or lunar rock is rock, found on the Earth's moon including lunar material collected during the course of human exploration of the Moon, or rock, ejected from the Moon's surface. Moon rocks on Earth come from three sources: those collected by the United States Apollo program manned lunar landings from 1969 to 1972; the Apollo missions collected 2,200 samples weighing 382 kilograms. Three Luna spacecraft returned with 301 grams of samples. More than 300 lunar meteorites have been collected on Earth, representing more than 30 different meteorite finds, with a total mass of over 190 kilograms; some were discovered by scientific teams searching for meteorites in Antarctica, with most of the remainder discovered by collectors in the desert regions of northern Africa and Oman. The Soviet Union attempted, but failed to make manned lunar landings in the 1970s, but they 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 fragments from Luna 16, weighing 200 mg, were sold for US$442,500. 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 4.28 billion years old. Moon rocks fall into two main categories: those found in the lunar highlands, those in the maria; the terrae consist dominantly of mafic plutonic rocks. Regolith breccias with similar protoliths are common. Mare basalts come in three distinct series in direct relation to their titanium content: high-Ti basalts, low-Ti basalts, Very Low-Ti basalts. All lunar rocks are depleted in volatiles and are lacking in hydrated minerals common in Earth rocks.
In some regards, lunar rocks are 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, scoops and core tubes. Most were photographed prior to collection to record the condition, they were placed inside sample bags and 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; the mare basalts have high iron values. Furthermore, some of the mare basalts have high levels of titanium. Primary igneous rocks in the lunar highlands compose three distinct groups: the ferroan anorthosite suite, the magnesian suite, the alkali suite. Lunar breccias, formed by the immense basin-forming impacts, are dominantly composed of highland lithologies because most mare basalts post-date basin formation; the ferroan anorthosite suite consists exclusively of the rock anorthosite with less common anorthositic gabbro.
The ferroan anorthosite suite is the most common group in the highlands, is inferred to represent plagioclase flotation cumulates 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 calcic by terrestrial standards, with molar anorthite contents of 94-96%; this reflects the extreme depletion of the bulk moon in alkalis 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 consists of dunites and gabbros with high Mg/Fe ratios in the mafic minerals and a range of plagioclase compositions that are still calcic; these rocks represent intrusions into the highlands crust 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 require 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 sodic plagioclase and gabbronorites with similar plagioclase compositions and mafic minerals more iron-rich than the magnesian suite; the trace element contents of these minerals indicates a KREEP-rich parent magma. The alkali suite spans an age range similar to the magnesian suite. Lunar granites are rare rocks that include diorites and granophyres, they consist of quartz, orthoclase or alkali feldspar, rare mafics, rare zircon. The alkali feldspar may have unusual compositions unlike any terrestrial felds
Apollo 17 was the final mission of NASA's Apollo program and the last mission as of 2019 in which humans have travelled to and walked on the Moon. Launched at 12:33 a.m. Eastern Standard Time on December 7, 1972, with a crew made up of Commander Eugene Cernan, Command Module Pilot Ronald Evans, Lunar Module Pilot Harrison Schmitt, it was the last use of Apollo hardware for its original purpose. Apollo 17 was the first night launch of a U. S. human spaceflight and the final manned launch of a Saturn V rocket. It was a "J-type mission" which included three days on the lunar surface, extended scientific capability, the third Lunar Roving Vehicle. While Evans remained in lunar orbit in the command and service module and Schmitt spent just over three days on the Moon in the Taurus–Littrow valley and completed three moonwalks, taking lunar samples and deploying scientific instruments. Evans took scientific measurements and photographs from orbit using a scientific instruments module mounted in the service module.
The landing site was chosen with the primary objectives of Apollo 17 in mind: to sample lunar highland material older than the impact that formed Mare Imbrium, investigate the possibility of new volcanic activity in the same area. Cernan and Schmitt returned to Earth on December 19 after a 12-day mission. Apollo 17 is the most recent manned Moon landing and the most recent time humans travelled beyond low Earth orbit, it was the first mission to have no one on board, a test pilot. The mission broke several records: the longest Moon landing, longest total extravehicular activities, largest lunar sample, longest time in lunar orbit. Eugene Cernan, Ronald Evans, former X-15 pilot Joe Engle were assigned to the backup crew of Apollo 14. Engle flew sixteen X-15 flights. Following the rotation pattern that a backup crew would fly as the prime crew three missions Cernan and Engle would have flown Apollo 17. Harrison Schmitt served on the backup crew of Apollo 15 and, following the crew rotation cycle, was slated to fly as Lunar Module Pilot on Apollo 18.
However, Apollo 18 was cancelled in September 1970. Following this decision, the scientific community pressured NASA to assign a geologist to an Apollo landing, as opposed to a pilot trained in geology. In light of this pressure, Harrison Schmitt, a professional geologist, was assigned the Lunar Module Pilot position on Apollo 17. Scientist-astronaut Curt Michel believed that it was his own decision to resign, after it became clear that he would not be given a flight assignment, that mobilized this action. Subsequent to the decision to assign Schmitt to Apollo 17, there remained the question of which crew would become prime crew of the mission. NASA Director of Flight Crew Operations Deke Slayton assigned the backup crew of Apollo 14, along with Schmitt, to the prime crew of Apollo 17; the Apollo 15 prime crew received the backup assignment since this was to be the last lunar mission and the backup crew would not rotate to another mission. However, when the Apollo 15 postage stamp incident became public in early 1972 the crew was reprimanded by NASA and the United States Air Force.
Director of Flight Crew Operations Deke Slayton removed them from flight status and replaced them with Young and Duke from the Apollo 16 prime crew and Roosa from the Apollo 14 prime and Apollo 16 backup crews. Robert F. Overmyer Robert A. Parker C. Gordon Fullerton The insignia's most prominent feature is an image of the Greek sun god Apollo backdropped by a rendering of an American eagle, the red bars on the eagle mirroring those on the flag of the United States. Three white stars above the red bars represent the three crewmen of the mission; the background includes the Moon, the planet Saturn, a galaxy or nebula. The wing of the eagle overlays the Moon, suggesting man's established presence there; the gaze of Apollo and the direction of the eagle's motion embody man's intention to explore further destinations in space. The patch includes, along with the colors of the U. S. flag, the color gold, representative of a "golden age" of spaceflight, to begin with Apollo 17. The image of Apollo in the mission insignia is a rendering of the Apollo Belvedere sculpture.
The insignia was designed with input from the crew. Like Apollo 15 and Apollo 16, Apollo 17 was slated to be a "J-mission," an Apollo mission type that featured lunar surface stays of three days, higher scientific capability, the usage of the Lunar Roving Vehicle. Since Apollo 17 was to be the final lunar landing of the Apollo program, high-priority landing sites that had not been visited were given consideration for potential exploration. A landing in the crater Copernicus was considered, but was rejected because Apollo 12 had obtained samples from that impact, three other Apollo expeditions had visited the vicinity of Mare Imbrium. A landing in the lunar highlands near the crater Tycho was considered, but was rejected because of the rough terrain found there and a landing on the lunar far side in the crater Tsiolkovskiy was rejected due to technical considerations and the operational costs of maintaining communication during surface operations. A landing in a region southwest of Mare Crisium was considered, but rejected on the grounds that a Soviet spacecraft could access t
Earth is the third planet from the Sun and the only astronomical object known to harbor life. According to radiometric dating and other sources of evidence, Earth formed over 4.5 billion years ago. Earth's gravity interacts with other objects in space the Sun and the Moon, Earth's only natural satellite. Earth revolves around the Sun in a period known as an Earth year. During this time, Earth rotates about its axis about 366.26 times. Earth's axis of rotation is tilted with respect to its orbital plane; the gravitational interaction between Earth and the Moon causes ocean tides, stabilizes Earth's orientation on its axis, slows its rotation. Earth is the largest of the four terrestrial planets. Earth's lithosphere is divided into several rigid tectonic plates that migrate across the surface over periods of many millions of years. About 71% of Earth's surface is covered with water by oceans; the remaining 29% is land consisting of continents and islands that together have many lakes and other sources of water that contribute to the hydrosphere.
The majority of Earth's polar regions are covered in ice, including the Antarctic ice sheet and the sea ice of the Arctic ice pack. Earth's interior remains active with a solid iron inner core, a liquid outer core that generates the Earth's magnetic field, a convecting mantle that drives plate tectonics. Within the first billion years of Earth's history, life appeared in the oceans and began to affect the Earth's atmosphere and surface, leading to the proliferation of aerobic and anaerobic organisms; some geological evidence indicates. Since the combination of Earth's distance from the Sun, physical properties, geological history have allowed life to evolve and thrive. In the history of the Earth, biodiversity has gone through long periods of expansion punctuated by mass extinction events. Over 99% of all species that lived on Earth are extinct. Estimates of the number of species on Earth today vary widely. Over 7.6 billion humans live on Earth and depend on its biosphere and natural resources for their survival.
Humans have developed diverse cultures. The modern English word Earth developed from a wide variety of Middle English forms, which derived from an Old English noun most spelled eorðe, it has cognates in every Germanic language, their proto-Germanic root has been reconstructed as *erþō. In its earliest appearances, eorðe was being used to translate the many senses of Latin terra and Greek γῆ: the ground, its soil, dry land, the human world, the surface of the world, the globe itself; as with Terra and Gaia, Earth was a personified goddess in Germanic paganism: the Angles were listed by Tacitus as among the devotees of Nerthus, Norse mythology included Jörð, a giantess given as the mother of Thor. Earth was written in lowercase, from early Middle English, its definite sense as "the globe" was expressed as the earth. By Early Modern English, many nouns were capitalized, the earth became the Earth when referenced along with other heavenly bodies. More the name is sometimes given as Earth, by analogy with the names of the other planets.
House styles now vary: Oxford spelling recognizes the lowercase form as the most common, with the capitalized form an acceptable variant. Another convention capitalizes "Earth" when appearing as a name but writes it in lowercase when preceded by the, it always appears in lowercase in colloquial expressions such as "what on earth are you doing?" The oldest material found in the Solar System is dated to 4.5672±0.0006 billion years ago. By 4.54±0.04 Bya the primordial Earth had formed. The bodies in the Solar System evolved with the Sun. In theory, a solar nebula partitions a volume out of a molecular cloud by gravitational collapse, which begins to spin and flatten into a circumstellar disk, the planets grow out of that disk with the Sun. A nebula contains gas, ice grains, dust. According to nebular theory, planetesimals formed by accretion, with the primordial Earth taking 10–20 million years to form. A subject of research is the formation of some 4.53 Bya. A leading hypothesis is that it was formed by accretion from material loosed from Earth after a Mars-sized object, named Theia, hit Earth.
In this view, the mass of Theia was 10 percent of Earth, it hit Earth with a glancing blow and some of its mass merged with Earth. Between 4.1 and 3.8 Bya, numerous asteroid impacts during the Late Heavy Bombardment caused significant changes to the greater surface environment of the Moon and, by inference, to that of Earth. Earth's atmosphere and oceans were formed by volcanic outgassing. Water vapor from these sources condensed into the oceans, augmented by water and ice from asteroids and comets. In this model, atmospheric "greenhouse gases" kept the oceans from freezing when the newly forming Sun had only 70% of its current luminosity. By 3.5 Bya, Earth's magnetic field was established, which helped prevent the atmosphere from being stripped away by the solar wind. A crust formed; the two models that explain land mass propose either a steady growth to the present-day forms or, more a rapid growth early in Earth history followed by a long-term steady continental area. Continents formed by plate tectonics
An astronaut or cosmonaut is a person trained by a human spaceflight program to command, pilot, or serve as a crew member of a spacecraft. Although reserved for professional space travelers, the terms are sometimes applied to anyone who travels into space, including scientists, politicians and tourists; until 2002, astronauts were sponsored and trained by governments, either by the military or by civilian space agencies. With the suborbital flight of the funded SpaceShipOne in 2004, a new category of astronaut was created: the commercial astronaut; the criteria for what constitutes human spaceflight vary. The Fédération Aéronautique Internationale Sporting Code for astronautics recognizes only flights that exceed an altitude of 100 kilometers. In the United States, professional and commercial astronauts who travel above an altitude of 50 miles are awarded astronaut wings; as of 17 November 2016, a total of 552 people from 36 countries have reached 100 km or more in altitude, of which 549 reached low Earth orbit or beyond.
Of these, 24 people have traveled beyond low Earth orbit, either to lunar orbit, the lunar surface, or, in one case, a loop around the Moon. Three of the 24–Jim Lovell, John Young and Eugene Cernan–did so twice; the three current astronauts who have flown without reaching low Earth orbit are spaceplane pilots Joe Walker, Mike Melvill, Brian Binnie, who participated in suborbital missions. As of 17 November 2016, under the U. S. definition, 558 people qualify as having reached space, above 50 miles altitude. Of eight X-15 pilots who exceeded 50 miles in altitude, only one exceeded 100 kilometers. Space travelers have spent over 41,790 man-days in space, including over 100 astronaut-days of spacewalks; as of 2016, the man with the longest cumulative time in space is Gennady Padalka, who has spent 879 days in space. Peggy A. Whitson holds the record for the most time in space by 377 days. In 1959, when both the United States and Soviet Union were planning, but had yet to launch humans into space, NASA Administrator T. Keith Glennan and his Deputy Administrator, Dr. Hugh Dryden, discussed whether spacecraft crew members should be called astronauts or cosmonauts.
Dryden preferred "cosmonaut", on the grounds that flights would occur in the cosmos, while the "astro" prefix suggested flight to the stars. Most NASA Space Task Group members preferred "astronaut", which survived by common usage as the preferred American term; when the Soviet Union launched the first man into space, Yuri Gagarin in 1961, they chose a term which anglicizes to "cosmonaut". In English-speaking nations, a professional space traveler is called an astronaut; the term derives from the Greek words ástron, meaning "star", nautes, meaning "sailor". The first known use of the term "astronaut" in the modern sense was by Neil R. Jones in his 1930 short story "The Death's Head Meteor"; the word itself had been known earlier. In Les Navigateurs de l'Infini by J.-H. Rosny aîné, the word astronautique was used; the word may have been inspired by "aeronaut", an older term for an air traveler first applied in 1784 to balloonists. An early use of "astronaut" in a non-fiction publication is Eric Frank Russell's poem "The Astronaut", appearing in the November 1934 Bulletin of the British Interplanetary Society.
The first known formal use of the term astronautics in the scientific community was the establishment of the annual International Astronautical Congress in 1950, the subsequent founding of the International Astronautical Federation the following year. NASA applies the term astronaut to any crew member aboard NASA spacecraft bound for Earth orbit or beyond. NASA uses the term as a title for those selected to join its Astronaut Corps; the European Space Agency uses the term astronaut for members of its Astronaut Corps. By convention, an astronaut employed by the Russian Federal Space Agency is called a cosmonaut in English texts; the word is an anglicisation of the Russian word kosmonavt, one who works in space outside the Earth's atmosphere, a space traveler, which derives from the Greek words kosmos, meaning "universe", nautes, meaning "sailor". Other countries of the former Eastern Bloc use variations of the Russian word kosmonavt, such as the Polish kosmonauta. Coinage of the term kosmonavt has been credited to Soviet aeronautics pioneer Mikhail Tikhonravov.
The first cosmonaut was Soviet Air Force pilot Yuri Gagarin the first person in space. Valentina Tereshkova, a Russian factory worker, was the first woman in space, as well as the first civilian among the Soviet cosmonaut or NASA astronaut corps to make a spaceflight. On March 14, 1995, Norman Thagard became the first American to ride to space on board a Russian launch vehicle, thus became the first "American cosmonaut". "Yǔ háng yuán" is used for astronauts and cosmonauts in general, while "Hángtiān yuán" is used for Chinese astronauts. Here, "Hángtiān" is defined as the navigation of outer space within the local star system, i.e. solar system. The phrase "tài kōng rén" is used in Hong Kong and Taiwan; the term taikonaut is used by some English-language news media organizations for professional space travelers from China. The word has featured in the Longman and Oxford English dictionaries, the latter of which desc
Planetary science or, more planetology, is the scientific study of planets and planetary systems and the processes that form them. It studies objects ranging in size from micrometeoroids to gas giants, aiming to determine their composition, formation and history, it is a interdisciplinary field growing from astronomy and earth science, but which now incorporates many disciplines, including planetary geology, atmospheric science, hydrology, theoretical planetary science and exoplanetology. Allied disciplines include space physics, when concerned with the effects of the Sun on the bodies of the Solar System, astrobiology. There are interrelated theoretical branches of planetary science. Observational research can involve a combination of space exploration, predominantly with robotic spacecraft missions using remote sensing, comparative, experimental work in Earth-based laboratories; the theoretical component involves mathematical modelling. Planetary scientists are located in the astronomy and physics or Earth sciences departments of universities or research centres, though there are several purely planetary science institutes worldwide.
There are several major conferences each year, a wide range of peer-reviewed journals. In the case of some exclusive planetary scientists, many of whom are in relation to the study of dark matter, they will seek a private research centre and initiate partnership research tasks; the history of planetary science may be said to have begun with the Ancient Greek philosopher Democritus, reported by Hippolytus as saying The ordered worlds are boundless and differ in size, that in some there is neither sun nor moon, but that in others, both are greater than with us, yet with others more in number. And that the intervals between the ordered worlds are unequal, here more and there less, that some increase, others flourish and others decay, here they come into being and there they are eclipsed, but that they are destroyed by colliding with one another. And that some ordered worlds are bare of animals and plants and all water. In more modern times, planetary science began from studies of the unresolved planets.
In this sense, the original planetary astronomer would be Galileo, who discovered the four largest moons of Jupiter, the mountains on the Moon, first observed the rings of Saturn, all objects of intense study. Galileo's study of the lunar mountains in 1609 began the study of extraterrestrial landscapes: his observation "that the Moon does not possess a smooth and polished surface" suggested that it and other worlds might appear "just like the face of the Earth itself". Advances in telescope construction and instrumental resolution allowed increased identification of the atmospheric and surface details of the planets; the Moon was the most studied, as it always exhibited details on its surface, due to its proximity to the Earth, the technological improvements produced more detailed lunar geological knowledge. In this scientific process, the main instruments were astronomical optical telescopes and robotic exploratory spacecraft; the Solar System has now been well-studied, a good overall understanding of the formation and evolution of this planetary system exists.
However, there are large numbers of unsolved questions, the rate of new discoveries is high due to the large number of interplanetary spacecraft exploring the Solar System. This is both a theoretical science. Observational researchers are predominantly concerned with the study of the small bodies of the Solar System: those that are observed by telescopes, both optical and radio, so that characteristics of these bodies such as shape, surface materials and weathering are determined, the history of their formation and evolution can be understood. Theoretical planetary astronomy is concerned with dynamics: the application of the principles of celestial mechanics to the Solar System and extrasolar planetary systems; the best known research topics of planetary geology deal with the planetary bodies in the near vicinity of the Earth: the Moon, the two neighbouring planets: Venus and Mars. Of these, the Moon was studied first. Geomorphology studies the features on planetary surfaces and reconstructs the history of their formation, inferring the physical processes that acted on the surface.
Planetary geomorphology includes the study of several classes of surface features: Impact features Volcanic and tectonic features Space weathering - erosional effects generated by the harsh environment of space. For example, the thin dust cover on the surface of the lunar regolith is a result of micro meteorite bombardment. Hydrological features: the liquid involved can range from water to hydrocarbon and ammonia, depending on the location within the Solar System; the history of a planetary surface can be deciphered by mapping features from top to bottom according to their deposition sequence, as first determined on terrestrial strata by Nicolas Steno. For example, stratigraphic mapping prepared the Apollo astronauts for the field geology they would encounter on their lunar missions. Overlapping sequences were identified on images taken by the Lunar Orbiter program, these were used to prepare a lunar stratigraphic column and geolog