LHSD
Journey To The Moon All about the moon Kiah Schauf Chase Robertson
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Table of Contents Composition of the moon…………………………………………………………page 3 How it was formed…………………………………………………………………….page 4 Its size and distance from Earth………………………………………………..page 5 Phases it has……………………………………………………………………………..page 6 Timeline of moon missions…………………………………………… ……………page 7-11
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Composition of the Moon
Chemical composition of the lunar surface regolith (derived from crustal rocks)[26] Composition (wt %) Compound Formula silica alumina lime iron(II) oxide magnesia titanium dioxide sodium oxide
SiO2 Al2O3 CaO FeO MgO TiO2 Na2O Total
Maria
Highlands
45.4% 14.9% 11.8% 14.1% 9.2% 3.9% 0.6% 99.9%
45.5% 24.0% 15.9% 5.9% 7.5% 0.6% 0.6% 100.0%
This is the moon’s basic chemical composition on the lunar surface.
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How the Moon Formed
Several mechanisms have been proposed for the Moon's formation 4.527 ± 0.010 billion years ago,[nb 6] some 30–50 million years after the origin of the Solar System.[12] These included the fission of the Moon from the Earth's crust through centrifugal force,[13] which would require too great an initial spin of the Earth,[14] the gravitational capture of a pre-formed Moon,[15] which would require an unfeasibly extended atmosphere of the Earth to dissipate the energy of the passing Moon,[14] and the co-formation of the Earth and the Moon together in the primordial accretion disk, which does not explain the depletion of metallic iron in the Moon.[14] These hypotheses also cannot account for the high angular momentum of the Earth–Moon system.[16] The prevailing hypothesis today is that the Earth–Moon system formed as a result of a giant impact: a Mars-sized body hitting the newly formed proto-Earth, blasting material into orbit around it, which accreted to form the Moon.[17] Giant impacts are thought to have been common in the early Solar System. Computer simulations modelling a giant impact are consistent with measurements of the angular momentum of the Earth–Moon system, and the small size of the lunar core; they also show that most of the Moon came from the impactor, not from the protoEarth.[18] More recent tests suggest more of the Moon coalesced from the Earth and not the impactor.[19][20][21]. Meteorites show that other inner Solar System bodies such as Mars and Vesta have very different oxygen and tungsten isotopic compositions to the Earth, while the Earth and Moon have near-identical isotopic compositions. Post-impact mixing of the vaporized material between the forming Earth and Moon could have equalized their isotopic compositions,[22] although this is debated.[23] The large amount of energy released in the giant impact event and the subsequent reaccretion of material in Earth orbit would have melted the outer shell of the Earth, forming a magma ocean.[24][25] The newly formed Moon would also have had its own lunar magma ocean; estimates for its depth range from about 500 km to the entire radius of the Moon.[24]
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Moon’s size and Distance from Earth The Moon is exceptionally large relative to the Earth: a quarter the diameter of the planet and 1/81 its mass.[42] It is the second largest moon orbiting an object in the solar system relative to the size of its planet. Charon is larger relative to the dwarf planet Pluto, at slightly more than 1/9 (11.6%) of Pluto's mass.[85] However, the Earth and Moon are still considered a planet–satellite system, rather than a doubleplanet system, as their barycentre, the common centre of mass, is located 1,700 km (about a quarter of the Earth's radius) beneath the surface of the Earth.[86] The Moon is in synchronous rotation: it rotates about its axis in about the same time it takes to orbit the Earth. This results in it nearly always keeping the same face turned towards the Earth. The Moon used to rotate at a faster rate, but early in its history, its rotation slowed and became tidally locked in this orientation as a result of frictional effects associated with tidal deformations caused by the Earth.[87] The side of the Moon that faces Earth is called the near side, and the opposite side the far side. The far side is often called the "dark side," but in fact, it is illuminated as often as the near side: once per lunar day, during the new Moon phase we observe on Earth when the near side is dark.[88] The Moon has an exceptionally low albedo, giving it a similar reflectance to coal. Despite this, it is the second brightest object in the sky after the Sun.[42][nb 9] This is partly due to the brightness enhancement of the opposition effect; at quarter phase, the Moon is only one-tenth as bright, rather than half as bright, as at full Moon.[89] Additionally, colour constancy in the visual system recalibrates the relations between the colours of an object and its surroundings, and since the surrounding sky is comparatively dark, the sunlit Moon is perceived as a bright object. The edges of the full Moon seem as bright as the centre, with no limb darkening, due to the reflective properties of lunar soil, which reflects more light back towards the Sun than in other directions. The Moon does appear larger when close to the horizon, but this is a purely psychological effect, known as the Moon illusion, first described in the 7th century BC.[90] The full Moon subtends an arc of about 0.52° (on average) in the sky, roughly the same apparent size as the Sun
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Phases of the Moon It's probably easiest to understand the moon cycle in this order: new moon and full moon, first quarter and third quarter, and the phases in between. As shown in the above diagram, the new moon occurs when the moon is positioned between the earth and sun. The three objects are in approximate alignment (why "approximate" is explained below). The entire illuminated portion of the moon is on the back side of the moon, the half that we cannot see. At a full moon, the earth, moon, and sun are in approximate alignment, just as the new moon, but the moon is on the opposite side of the earth, so the entire sunlit part of the moon is facing us. The shadowed portion is entirely hidden from view. The first quarter and third quarter moons (both often called a "half moon"), happen when the moon is at a 90 degree angle with respect to the earth and sun. So we are seeing exactly half of the moon illuminated and half in shadow. Once you understand those four key moon phases, the phases between should be fairly easy to visualize, as the illuminated portion gradually transitions between them. An easy way to remember and understand those "between" lunar phase names is by breaking out and defining 4 words: crescent, gibbous, waxing, and waning. The word crescent refers to the phases where the moon is less that half illuminated. The word gibbous refers to phases where the moon is more than half illuminated. Waxing essentially means "growing" or expanding in illumination, and waning means "shrinking" or decreasing in illumination. Thus you can simply combine the two words to create the phase name, as follows: After the new moon, the sunlit portion is increasing, but less than half, so it is waxing crescent. After the first quarter, the sunlit portion is still increasing, but now it is more than half, so it is waxing gibbous. After the full moon (maximum illumination), the light continually decreases. So the waning gibbous phase occurs next. Following the third quarter is the waning crescent, which wanes until the light is completely gone -- a new moon. 6
Timeline for Moon Missions 1959
Luna 1 - Jan 2, 1959 - Flyby Pioneer 4 - Mar 3, 1959 - Flyby Luna 2 - Sep 12, 1959 - Impact Luna 3 - Oct 4, 1959 - Probe 1960 1961 Ranger 1 - Aug 23, 1961 - Attempted Test Flight Ranger 2 - Nov 18, 1961 - Attempted Test Flight 1962 Ranger 3 - Jan 26, 1962 - Attempted Impact Ranger 4 - Apr 23, 1962 - Impact Ranger 5 - Oct 18, 1962 - Attempted Impact 1963 Luna 4 - Apr 2, 1963 - Flyby 1964 Ranger 6 - Jan 30, 1964 - Impact Ranger 7 - Jul 28, 1964 - Impact 1965 Ranger 8 - Feb 17, 1965 - Impact Ranger 9 - Mar 21, 1965 - Impact Luna 5 - May 9, 1965 - Impact Luna 6 - Jun 8, 1965 - Attempted Lander Zond 3 - Jul 18, 1965 - Flyby Luna 7 - Oct 4, 1965 - Impact Luna 8 - Dec 3, 1965 - Impact 1966 Luna 9 - Jan 31, 1966 - Lander Luna 10 - Mar 31, 1966 - Orbiter 7
Surveyor 1 - May 30, 1966 - Lander Lunar Orbiter 1 - Aug 10, 1966 - Orbiter Luna 11 - Aug 24, 1966 - Orbiter Surveyor 2 - Sep 20, 1966 - Attempted Lander Luna 12 - Oct 22, 1966 - Orbiter Lunar Orbiter 2 - Nov 6, 1966 - Orbiter Luna 13 - Dec 21, 1966 - Lander 1967 Lunar Orbiter 3 - Feb 4, 1967 - Orbiter Surveyor 3 - Apr 17, 1967 - Lander Lunar Orbiter 4 - May 8, 1967 - Orbiter Surveyor 4 - Jul 14, 1967 - Attempted Lander Explorer 35 (IMP-E) - Jul 19, 1967 - Orbiter Lunar Orbiter 5 - Aug 1, 1967 - Orbiter Surveyor 5 - Sep 8, 1967 - Lander Surveyor 6 - Nov 7, 1967 - Lander 1968 Surveyor 7 - Jan 7, 1968 - Lander Luna 14 - Apr 7, 1968 - Orbiter Zond 5 - Sep 15, 1968 - Return Probe Zond 6 - Nov 10, 1968 - Return Probe Apollo 8 - Dec 21, 1968 - Crewed Orbiter 1969 Apollo 10 - May 18, 1969 - Orbiter Luna 15 - Jul 13, 1969 - Orbiter Apollo 11 - Jul 16, 1969 - Crewed Landing Zond 7 - Aug 7, 1969 - Return Probe Apollo 12 - Nov 14, 1969 - Crewed Landing 1970 Apollo 13 - Apr 11, 1970 - Crewed Landing (aborted) Luna 16 - Sep 12, 1970 - Sample Return Zond 8 - Oct 20, 1970 - Return Probe 8
Luna 17 - Nov 10, 1970 - Rover 1971 Apollo 14 - Jan 31, 1971 - Crewed Landing Apollo 15 - Jul 26, 1971 - Crewed Landing Luna 18 - Sep 2, 1971 - Impact Luna 19 - Sep 28, 1971 - Orbiter 1972 Luna 20 - Feb 14, 1972 - Sample Return Apollo 16 - Apr 16, 1972 - Crewed Landing Apollo 17 - Dec 7, 1972 - Crewed Landing 1973 Luna 21 - Jan 8, 1973 - Rover Explorer 49 (RAE-B) - Jun 10, 1973 - Orbiter 1974 Luna 22 - Jun 2, 1974 - Orbiter Luna 23 - Oct 28, 1974 - Lander 1975 1976 Luna 24 - Aug 14, 1976 - Sample Return 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 9
1990 Hiten - Jan 24, 1990 - Flyby and Orbiter 1991 1992 1993 1994 Clementine - Jan 25, 1994 - Orbiter 1995 1996 1997 AsiaSat 3/HGS-1 - Dec 24, 1997 - Lunar Flyby 1998 Lunar Prospector - Jan 7, 1998 - Orbiter 1999 2000 2001 2002 2003 SMART 1 - Sep 27, 2003 - Lunar Orbiter 2004 2005 2006 2007 Kaguya (SELENE) - Sep 14, 2007 - Lunar Orbiter Chang'e 1 - Oct 24, 2007 - Lunar Orbiter 2008 Chandrayaan-1 - Oct 22, 2008 - Lunar Orbiter 2009 Lunar Reconnaissance Orbiter - June 17, 2009 - Lunar Orbiter LCROSS - June 17, 2009 - Lunar Orbiter and Impactor 2010 Chang'e 2 - Oct 1, 2010 - Lunar Orbiter 10
2011 Gravity Recovery And Interior Laboratory (GRAIL) - Sep 10, 2011 - Lunar Orbiter 2012 2013 Lunar Atmosphere and Dust Environment Explorer (LADEE) - Mar, 2013 - Lunar Orbiter
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