Bulan: Perbedaan antara revisi
Konten dihapus Konten ditambahkan
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Tidak ada ringkasan suntingan |
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Baris 81:
Hipotesis yang berlaku saat ini menjelaskan bahwa sistem Bumi-Bulan terbentuk akibat [[Hipotesis tubrukan besar|tubrukan besar]], ketika benda langit seukuran [[Mars]] (bernama ''[[Theia (planet)|Theia]]'') bertabrakan dengan [[Sejarah Bumi|proto-Bumi]] yang baru terbentuk, memuntahkan material ke orbit di sekitarnya yang kemudian berkumpul untuk membentuk Bulan.<ref name="taylor1998" /> Hipotesis ini mungkin merupakan hipotesis yang paling menjelaskan mengenai asal usul Bulan, meskipun penjelasannya tidak sempurna.
Tubrukan besar diperkirakan
Besarnya energi yang dilepaskan saat terjadinya tubrukan besar dan akresi materi di orbit Bumi yang terjadi setelahnya akan melelehkan kulit bagian luar Bumi, yang kemudian membentuk lautan magma.<ref name="Warren1985" /><ref>{{cite journal|last=Tonks|first=W. Brian|coauthors=Melosh, H. Jay|year=1993|title=Magma ocean formation due to giant impacts|journal=Journal of Geophysical Research|volume=98|issue=E3|pages=5319–5333|bibcode=1993JGR....98.5319T|doi=10.1029/92JE02726}}</ref> Bulan yang baru terbentuk juga memiliki [[lautan magma Bulan|lautan magma]] sendiri; diperkirakan kedalamannya sekitar 500 km dari radius keseluruhan Bulan.<ref name="Warren1985" />
Baris 193:
== Referensi ==
;Catatan
{{notes
| notes =
{{efn
| name = maxval
| The ''maximum value'' is given based on scaling of the brightness from the value of −12.74 given for an equator to Moon-centre distance of 378 000 km in the NASA factsheet reference to the minimum Earth–Moon distance given there, after the latter is corrected for Earth's equatorial radius of 6 378 km, giving 350 600 km. The ''minimum value'' (for a distant [[new moon]]) is based on a similar scaling using the maximum Earth–Moon distance of 407 000 km (given in the factsheet) and by calculating the brightness of the [[earthshine]] onto such a new moon. The brightness of the earthshine is {{nowrap|[ Earth [[albedo]] ×}} {{nowrap|([[Earth radius]] /}} Radius of [[Orbit of the Moon|Moon's orbit]])<sup>2</sup> ] relative to the direct solar illumination that occurs for a full moon. ({{nowrap|Earth albedo {{=}} 0.367}}; {{nowrap|Earth radius {{=}} (polar}} radius × equatorial {{nowrap|radius)<sup>½</sup> {{=}} 6 367 km}}.)
}}
{{efn
| name = angular size
| The range of angular size values given are based on simple scaling of the following values given in the fact sheet reference: at an Earth-equator to Moon-centre distance of 378 000 km, the [[Angular diameter|angular size]] is 1896 [[arcsecond]]s. The same fact sheet gives extreme Earth–Moon distances of 407 000 km and 357 000 km. For the maximum angular size, the minimum distance has to be corrected for Earth's equatorial radius of 6 378 km, giving 350 600 km.
}}
{{efn
| name = pressure explanation
| Lucey ''et al.'' (2006) give {{nowrap|10<sup>7</sup> particles cm<sup>−3</sup>}} by day and {{nowrap|10<sup>5</sup> particles cm<sup>−3</sup>}} by night. Along with equatorial surface temperatures of 390 [[Kelvin|K]] by day and 100 K by night, the [[ideal gas law]] yields the pressures given in the infobox (rounded to the nearest [[order of magnitude]]): 10<sup>−7</sup> [[Pascal (unit)|Pa]] by day and 10<sup>−10</sup> Pa by night.
}}
{{efn
| name = near-Earth asteroids
| There are a number of [[near-Earth asteroid]]s, including [[3753 Cruithne]], that are [[co-orbital]] with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term (Morais et al, 2002). These are [[quasi-satellite]]s – they are not moons as they do not orbit Earth. For more information, see [[Other moons of Earth]].
}}
{{efn
| name = Charon and Pluto
| [[Charon (moon)|Charon]] is proportionally larger in comparison to [[Pluto]], but Pluto has been reclassified as a [[dwarf planet]].
}}
{{efn
| name = age
| This age is calculated from isotope dating of lunar rocks.
}}
}}
;Rujukan
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