Moon - Composition. More than 4.5 billion years ago, the surface of the Moon was a liquid magma ocean. Scientists think that one component of lunar rocks, KREEP (K-potassium, Rare Earth Elements, and P-phosphorus), represents the last chemical remnant of that magma ocean. KREEP is actually a composite of what scientists term "incompatible elements": those which cannot fit into a crystal structure and thus were left behind, floating to the surface of the magma. For researchers, KREEP is a convenient tracer, useful ...

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Moon, Moon - The two sides, Moon - Orbit, Moon - Earth & Moon, Moon - Origin and history, Moon - Physical characteristics, Moon - Composition, Moon - Selenography, Moon - Presence of water, Moon - Magnetic field, Moon - Atmosphere, Moon - Eclipses, Moon - Occultation of stars, Moon - Observation of the Moon, Moon - Exploration of the Moon, Moon - Human understanding of the Moon, Moon - Myth and folk culture, Moon - The Moon as muse, Moon - Astrology, Moon - Scientific understanding, Moon - Meteor impact on the Moon, Moon - Legal status, Moon - Satellites, Moon - Surface installations, Moon - Lunar location listings

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The inclination of the Moon's orbit makes it implausible that the Moon formed along with the Earth or was captured later; its origin is the subject of some scientific debate. Early speculation proposed that the Moon broke off from the Earth's crust due to centrifugal force, leaving an ocean basin (presumed to be the Pacific) behind as a scar. This concept requires too great an initial spin of the Earth and the presumption of a Pacific origin is not compatible with the geological standard model, the theory of plate tectonics. Others sp ...

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Moon, Moon - The two sides, Moon - Orbit, Moon - Earth & Moon, Moon - Origin and history, Moon - Physical characteristics, Moon - Composition, Moon - Selenography, Moon - Presence of water, Moon - Magnetic field, Moon - Atmosphere, Moon - Eclipses, Moon - Occultation of stars, Moon - Observation of the Moon, Moon - Exploration of the Moon, Moon - Human understanding of the Moon, Moon - Myth and folk culture, Moon - The Moon as muse, Moon - Astrology, Moon - Scientific understanding, Moon - Meteor impact on the Moon, Moon - Legal status, Moon - Satellites, Moon - Surface installations, Moon - Lunar location listings

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The far side is sometimes called the "dark side". In this case "dark" means "unknown and hidden" and not "lacking light" as implied by the name; in fact the far side receives (on average) as much sunlight as the near side, but at opposite times. Spacecraft are cut off from direct radio communication with the Earth when on the far side of the Moon. One distinguishing feature of the far side is its almost complete lack of maria (singular: mare ...

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Moon, Moon - The two sides, Moon - Orbit, Moon - Earth & Moon, Moon - Origin and history, Moon - Physical characteristics, Moon - Composition, Moon - Selenography, Moon - Presence of water, Moon - Magnetic field, Moon - Atmosphere, Moon - Eclipses, Moon - Occultation of stars, Moon - Observation of the Moon, Moon - Exploration of the Moon, Moon - Human understanding of the Moon, Moon - Myth and folk culture, Moon - The Moon as muse, Moon - Astrology, Moon - Scientific understanding, Moon - Meteor impact on the Moon, Moon - Legal status, Moon - Satellites, Moon - Surface installations, Moon - Lunar location listings

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The tides on Earth are generated by the Moon's gravitation (see tide and tidal force for a more detailed discussion). There are two tidal bulges, one in the direction of the Moon, and one in the opposite direction (figure 1). The buildup of these bulges and their movement around the earth causes an energy loss due to friction. The energy loss decreases the rotational energy of the Earth. Since the Earth spins faster than the Moon moves around it, the tidal bulges are dragged along with the Earth's surface faster than the Moon moves, a ...

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Moon, Moon - The two sides, Moon - Orbit, Moon - Earth & Moon, Moon - Origin and history, Moon - Physical characteristics, Moon - Composition, Moon - Selenography, Moon - Presence of water, Moon - Magnetic field, Moon - Atmosphere, Moon - Eclipses, Moon - Occultation of stars, Moon - Observation of the Moon, Moon - Exploration of the Moon, Moon - Human understanding of the Moon, Moon - Myth and folk culture, Moon - The Moon as muse, Moon - Astrology, Moon - Scientific understanding, Moon - Meteor impact on the Moon, Moon - Legal status, Moon - Satellites, Moon - Surface installations, Moon - Lunar location listings

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During the brightest full moons, the Moon can have an apparent magnitude of about −12.6. For comparison, the Sun has an apparent magnitude of −26.8. The Moon appears larger when close to the horizon. This is a purely psychological effect (see Moon illusion). The angular diameter of the Moon from Earth is about one half of one degree, and is actually about 1.5% smaller when the Moon is near the horizon than when it is high in the sky (beca ...

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Moon, Moon - The two sides, Moon - Orbit, Moon - Earth & Moon, Moon - Origin and history, Moon - Physical characteristics, Moon - Composition, Moon - Selenography, Moon - Presence of water, Moon - Magnetic field, Moon - Atmosphere, Moon - Eclipses, Moon - Occultation of stars, Moon - Observation of the Moon, Moon - Exploration of the Moon, Moon - Human understanding of the Moon, Moon - Myth and folk culture, Moon - The Moon as muse, Moon - Astrology, Moon - Scientific understanding, Moon - Meteor impact on the Moon, Moon - Legal status, Moon - Satellites, Moon - Surface installations, Moon - Lunar location listings

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The first leap in Lunar observation was caused by the invention of the telescope. Especially Galileo Galilei made good use of this new instrument and observed mountains and craters on the Moon's surface. The Cold War-inspired space race between the Soviet Union and the United States of America led to an acceleration. What was the next big step depends on the political viewpoint: In the US (and the West in general) the landing of the first humans on the moon in 1969 is seen as a culmination, indeed of the space race in general. On the ...

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Moon, Moon - The two sides, Moon - Orbit, Moon - Earth & Moon, Moon - Origin and history, Moon - Physical characteristics, Moon - Composition, Moon - Selenography, Moon - Presence of water, Moon - Magnetic field, Moon - Atmosphere, Moon - Eclipses, Moon - Occultation of stars, Moon - Observation of the Moon, Moon - Exploration of the Moon, Moon - Human understanding of the Moon, Moon - Myth and folk culture, Moon - The Moon as muse, Moon - Astrology, Moon - Scientific understanding, Moon - Meteor impact on the Moon, Moon - Legal status, Moon - Satellites, Moon - Surface installations, Moon - Lunar location listings

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Colonization of the Moon - Habitat. There have been numerous proposals regarding the habitat modules. The designs have evolved throughout the years as humankind's knowledge about the Moon has grown, and as the technological possibilities have changed. The proposed habitats range from the actual spacecraft landers or the used fuel tanks, to inflatable modules of various shapes. Early on, some hazards of the lunar environment such as sharp temperature shifts, lack of atmosphere or magnetic field (which means higher levels of radiation and micrometeoroids) and long ...

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Colonization of the Moon, Colonization of the Moon - History, Colonization of the Moon - Exploration phase, Colonization of the Moon - Advantages and disadvantages, Colonization of the Moon - Advantages, Colonization of the Moon - Disadvantages, Colonization of the Moon - Locations, Colonization of the Moon - Polar regions, Colonization of the Moon - Equatorial regions, Colonization of the Moon - Far side, Colonization of the Moon - Structure, Colonization of the Moon - Habitat, Colonization of the Moon - Energy, Colonization of the Moon - Transport, Colonization of the Moon - On the surface, Colonization of the Moon - Surface to space, Colonization of the Moon - Economic development, Colonization of the Moon - Moon colonies in fiction and film, Colonization of the Moon - Books, Colonization of the Moon - Television, Colonization of the Moon - Film, Colonization of the Moon - Computer and video games

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For long term sustainability, a space colony should be close to self sufficient. On site mining and refining of the Moon's materials could provide an advantage over deliveries from Earth – for use both on the Moon and elsewhere in the solar system – as they can be launched into space at a much lower energy cost than from Earth. It is possible that vast sums of money will be spent in interplanetary exploration in the 21st century, a ...

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Colonization of the Moon, Colonization of the Moon - History, Colonization of the Moon - Exploration phase, Colonization of the Moon - Advantages and disadvantages, Colonization of the Moon - Advantages, Colonization of the Moon - Disadvantages, Colonization of the Moon - Locations, Colonization of the Moon - Polar regions, Colonization of the Moon - Equatorial regions, Colonization of the Moon - Far side, Colonization of the Moon - Structure, Colonization of the Moon - Habitat, Colonization of the Moon - Energy, Colonization of the Moon - Transport, Colonization of the Moon - On the surface, Colonization of the Moon - Surface to space, Colonization of the Moon - Economic development, Colonization of the Moon - Moon colonies in fiction and film, Colonization of the Moon - Books, Colonization of the Moon - Television, Colonization of the Moon - Film, Colonization of the Moon - Computer and video games

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Russian astronomer Vladislav V. Shevchenko proposed in 1988 three criteria that a lunar outpost should meet: good conditions for transport operations; a great number of different types of natural objects and features on the Moon of scientific interest; and natural resources, such as oxygen. While a colony might be located anywhere, potential locations for a lunar colony fall into three broad categories. See also:

Colonization of the Moon, Colonization of the Moon - History, Colonization of the Moon - Exploration phase, Colonization of the Moon - Advantages and disadvantages, Colonization of the Moon - Advantages, Colonization of the Moon - Disadvantages, Colonization of the Moon - Locations, Colonization of the Moon - Polar regions, Colonization of the Moon - Equatorial regions, Colonization of the Moon - Far side, Colonization of the Moon - Structure, Colonization of the Moon - Habitat, Colonization of the Moon - Energy, Colonization of the Moon - Transport, Colonization of the Moon - On the surface, Colonization of the Moon - Surface to space, Colonization of the Moon - Economic development, Colonization of the Moon - Moon colonies in fiction and film, Colonization of the Moon - Books, Colonization of the Moon - Television, Colonization of the Moon - Film, Colonization of the Moon - Computer and video games

Read more here: » Colonization of the Moon: Encyclopedia II - Colonization of the Moon - Locations

Putting aside the general questions of whether a human colony beyond the Earth is feasible or desirable (see: space colonization for a discussion of this question), proponents of space colonization point out that the Moon offers both advantages and disadvantages as a site for such a colony. Colonization of the Moon - Advantages. Placing a colony on a natural body would provide an ample source of material for construction and other uses, including shielding from radiation. The energy required to send ...

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Colonization of the Moon, Colonization of the Moon - History, Colonization of the Moon - Exploration phase, Colonization of the Moon - Advantages and disadvantages, Colonization of the Moon - Advantages, Colonization of the Moon - Disadvantages, Colonization of the Moon - Locations, Colonization of the Moon - Polar regions, Colonization of the Moon - Equatorial regions, Colonization of the Moon - Far side, Colonization of the Moon - Structure, Colonization of the Moon - Habitat, Colonization of the Moon - Energy, Colonization of the Moon - Transport, Colonization of the Moon - On the surface, Colonization of the Moon - Surface to space, Colonization of the Moon - Economic development, Colonization of the Moon - Moon colonies in fiction and film, Colonization of the Moon - Books, Colonization of the Moon - Television, Colonization of the Moon - Film, Colonization of the Moon - Computer and video games

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Though several flags of the Soviet Union and the United States have been symbolically planted on the moon, the Russian and U.S. governments make no claims to any part of the Moon's surface. Russia and the U.S. are party to the Outer Space Treaty, which places the Moon under the same jurisdiction as international waters (res communis). This treaty also restricts use of the Moon to peaceful purposes, explicitly banning weapons of mass destruction (including nuclear weapons) and military installations of any kind. A second treaty, the Moon Trea ...

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Moon, Moon - The two sides, Moon - Orbit, Moon - Earth & Moon, Moon - Origin and history, Moon - Physical characteristics, Moon - Composition, Moon - Selenography, Moon - Presence of water, Moon - Magnetic field, Moon - Atmosphere, Moon - Eclipses, Moon - Occultation of stars, Moon - Observation of the Moon, Moon - Exploration of the Moon, Moon - Human understanding of the Moon, Moon - Myth and folk culture, Moon - The Moon as muse, Moon - Astrology, Moon - Scientific understanding, Moon - Meteor impact on the Moon, Moon - Legal status, Moon - Satellites, Moon - Surface installations, Moon - Lunar location listings

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Moon colonies are found in many science fiction novels, short stories and films. Not all have the Moon colony itself as central to the plot. Here are some notable examples: Colonization of the Moon - Books. The Moon is a Harsh Mistress, a classic science fiction novel by Robert A. Heinlein, tells the story of a lunar rebellion against control by Earth-based governments. The short story People Came From Earth by Stephen Baxter. It can be found in The Year's Best Science Ficti ...

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Colonization of the Moon, Colonization of the Moon - History, Colonization of the Moon - Exploration phase, Colonization of the Moon - Advantages and disadvantages, Colonization of the Moon - Advantages, Colonization of the Moon - Disadvantages, Colonization of the Moon - Locations, Colonization of the Moon - Polar regions, Colonization of the Moon - Equatorial regions, Colonization of the Moon - Far side, Colonization of the Moon - Structure, Colonization of the Moon - Habitat, Colonization of the Moon - Energy, Colonization of the Moon - Transport, Colonization of the Moon - On the surface, Colonization of the Moon - Surface to space, Colonization of the Moon - Economic development, Colonization of the Moon - Moon colonies in fiction and film, Colonization of the Moon - Books, Colonization of the Moon - Television, Colonization of the Moon - Film, Colonization of the Moon - Computer and video games

Read more here: » Colonization of the Moon: Encyclopedia II - Colonization of the Moon - Moon colonies in fiction and film