Muin
anerly naitural satellite o Yird / From Wikipedia, the free encyclopedia
The Muin is an astronomical bouk that orbits planet Yird, bein Yird's anerly permanent naitural satellite. It is the fift-lairgest naitural satellite in the Solar Seestem, an the lairgest amang planetar satellites relative tae the size o the planet that it orbits (its primar). Follaein Jupiter's satellite Io, the Muin is seicond-densest satellite amang thae whase densities are kent.
The "Scots" that wis uised in this airticle wis written bi a body that haesna a guid grip on the leid. Please mak this airticle mair better gin ye can. |
Full muin as seen frae Yird's Northren Hemisphere | |||||||||||||
Designations | |||||||||||||
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Adjectives | |||||||||||||
Orbital chairactereestics | |||||||||||||
Perigee | 362600 km (356400–370400 km) | ||||||||||||
Apogee | 405400 km (404000–406700 km) | ||||||||||||
7008384399000000000♠384399 km (7008384466527698999♠0.00257 AU)[1] | |||||||||||||
Eccentricity | 6998549000000000000♠0.0549[1] | ||||||||||||
Orbital period | |||||||||||||
Synodic period | 7006255144288960000♠29.530589 d (29 d 12 h 44 min 2.9 s) | ||||||||||||
Average orbital speed | 7003102200000000000♠1.022 km/s | ||||||||||||
Inclination | 5.145° tae the ecliptic[2][lower-alpha 1] | ||||||||||||
Longitude o ascendin node | Regressin bi ane revolution in 18.61 years | ||||||||||||
Argument o perigee | Progressin bi ane revolution in 8.85 years | ||||||||||||
Satellite o | Yird[lower-alpha 2][3] | ||||||||||||
Pheesical chairacteristics | |||||||||||||
Mean radius | 7006173710000000000♠1737.1 km (0.273 o Yird's)[1][4][5] | ||||||||||||
Equatorial radius | 7006173810000000000♠1738.1 km (0.273 o Yird's)[4] | ||||||||||||
Polar radius | 7006173600000000000♠1736.0 km (0.273 o Yird's)[4] | ||||||||||||
Flettenin | 6997119999999999999♠0.0012[4] | ||||||||||||
Circumference | 7007109210000000000♠10921 km (equatorial) | ||||||||||||
Surface area | 7013379300000000000♠3.793×107 km2 (0.074 o Yird's) | ||||||||||||
Vollum | 7019219580000000000♠2.1958×1010 km3 (0.020 o Yird's)[4] | ||||||||||||
Mass | 7022734200000000000♠7.342×1022 kg (6998123000000000000♠0.012300 o Yird's)[1][4] | ||||||||||||
Mean density | 7003334400000000000♠3.344 g/cm3[1][4] 6999606000000000000♠0.606 × Yird | ||||||||||||
Surface gravity | 7000162000000000000♠1.62 m/s2 (6999165400000000000♠0.1654 g)[4] | ||||||||||||
Moment o inertia factor | 6999392900000000000♠0.3929±0.0009[6] | ||||||||||||
Escape velocity | 7003238000000000000♠2.38 km/s | ||||||||||||
Sidereal rotation period | 7006236059151040000♠27.321661 d (synchronous) | ||||||||||||
Equatorial rotation velocity | 4.627 m/s | ||||||||||||
Axial tilt |
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Albedo | 0.136[7] | ||||||||||||
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Apparent magnitude |
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Angular diameter | 29.3 tae 34.1 arcmeenits[4][lower-alpha 4] | ||||||||||||
Atmosphere[9] | |||||||||||||
Surface pressur |
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Composeetion bi vollum | |||||||||||||
The Muin is thocht tae hae formed aboot 4.51 billion year ago, nae lang efter Yird. The maist widely acceptit explanation is that the Muin formed frae the debris left ower efter a giant impact atween Yird an a Maurs-sized bouk cried Theia.
The Muin is in synchronous rotation wi Yird, ayeweys shawin the same face, wi its near side merked bi daurk volcanic maria that fill the spaces atween the bricht auncient crustal hielands an the prominent impact craters. As seen frae the Yird, it is the seicont-brichtest regularly veesible celestial object in Yird's sky, efter the Sun. Its surface is actually daurk, awtho compared tae the nicht sky it appears verra bricht, wi a reflectance juist slichtly heicher nor that o worn asphalt. Its gravitational influence produces the ocean tides, bouk tides, an the slicht lenthenin o the day.
The Muin's current orbital distance is 384,400 km (238,900 mi),[10][11] or 1.28 licht-seiconts. This is aboot thirty times the diameter o Yird, wi its apparent size in the sky awmaist the same as that o the Sun, resultin in the Muin coverin the Sun nearly precisely in tot solar eclipse. This matchin o apparent veesual size will nae conteena in the faur futur, acause the Muin's distance frae Yird is slawly increasin.
The Soviet Union's Luna programme wis the first tae reach the Muin wi uncrewed spacecraft in 1959; the Unitit States' NASA Apollo program achieved the anerly crewed missions tae date, beginnin wi the first crewed lunar orbitin mission bi Apollo 8 in 1968, an sax crewed lunar laundins atween 1969 an 1972, wi the first bein Apollo 11. Thir missions returned lunar rocks that hae been uised tae develop a geological unnerstaundin o the Muin's oreegin, internal structur, an later history. Syne the Apollo 17 mission in 1972, the Muin haes been veesitit anerly bi uncrewed spacecraft.
Athin human cultur, baith the Muin's naitural prominence in the yirdly sky, an its regular cycle o phases as seen frae the Yird hae providit cultural references an influences for human societies an culturs syne time immemorial. Sic cultural influences can be foond in leid, lunar based calendar seestems, airt, an meethologie.