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| | {{Planet|image=Moon2.jpg | | {{Planet|image=Moon2.jpg |
| − | |caption= The Moon in its third quarter phase | + | |caption= The Moon in its third-quarter phase |
| | |primary=Earth | | |primary=Earth |
| | |periapsis=363,300 km<ref name=moonfact>Williams, David R. (bef. March 7, 1996). [http://nssdc.gsfc.nasa.gov/planetary/factsheet/moonfact.html "Moon Fact Sheet"]. [[NASA]] website/Goddard Space Flight Center/NASA Space Science Data Coordinated Archive/Lunar and Planetary Science/Planetary Fact Sheet. January 2020 edition.</ref> | | |periapsis=363,300 km<ref name=moonfact>Williams, David R. (bef. March 7, 1996). [http://nssdc.gsfc.nasa.gov/planetary/factsheet/moonfact.html "Moon Fact Sheet"]. [[NASA]] website/Goddard Space Flight Center/NASA Space Science Data Coordinated Archive/Lunar and Planetary Science/Planetary Fact Sheet. January 2020 edition.</ref> |
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| | |mdt=364 a<ref name=Humphreys/> | | |mdt=364 a<ref name=Humphreys/> |
| | |mhl=252.3 a<ref name=calc group=note>Calculated</ref> | | |mhl=252.3 a<ref name=calc group=note>Calculated</ref> |
| − | }}A '''moon''' is a body which orbits a [[planet]]. The [[Earth]]'s Moon (sometimes known as "Luna") is a natural [[satellite]] orbiting Earth at an average distance of about 238,000 miles (380,000 km). It is the basis for our monthly calendar: a full moon occurs roughly once per month.<ref>https://answersingenesis.org/astronomy/the-splendor-of-gods-creation/</ref> | + | }} |
| | + | A '''moon''' is a body which orbits a [[planet]]. The [[Earth]]'s Moon (sometimes known as "Luna") is a natural [[satellite]] orbiting Earth at an average distance of about 238,000 miles (380,000 km). It is the basis for our monthly calendar: a full moon occurs roughly once per month.<ref>https://answersingenesis.org/astronomy/the-splendor-of-gods-creation/</ref> |
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| − | The Moon is unique in the solar system in its large relative size compared with the [[Earth]]. The Moon appears from the Earth to be the same size as the [[sun]], in perfect artistic symmetry, unlike any known other planet-moon system. Moreover, unlike most planets in the [[solar system]], [[Earth]] has only one moon, which is designed in two remarkable ways: (1) it rotates and revolves such that only one side is ever visible to the Earth (the only known moon with this characteristic)<ref>Some attribute the remarkable orbit and rotation of the Moon as being due to tidal locking.</ref> and (2) its side that faces the Earth is smooth, while the side that remains hidden is jagged. To those on Earth the Moon appears as an artistic disc that goes through phases of varying visibility from Earth. | + | The Moon is unique in the solar system in its large relative size compared with the [[Earth]]. The Moon appears from the Earth to be the same size as the [[sun]], in perfect artistic symmetry, unlike any known other planet-moon system. Moreover, unlike most planets in the [[solar system]], [[Earth]] has only one moon, which is designed in two remarkable ways: (1) it rotates and revolves such that only one side is ever visible to the Earth (the only known moon with this characteristic)<ref>Some attribute the remarkable orbit and rotation of the Moon as being due to tidal locking.</ref> and (2) its side that faces the Earth is smooth, while the side that remains hidden is jagged. To those on [[Earth]], the Moon appears as an artistic disc that goes through phases of varying visibility from Earth. |
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| | '''''The [[Bible]] states that the Moon was created separately on Day Four along with the Sun and stars, while [[atheistic science]] has no theory for the Moon's origin that is supported by any real evidence'''''. | | '''''The [[Bible]] states that the Moon was created separately on Day Four along with the Sun and stars, while [[atheistic science]] has no theory for the Moon's origin that is supported by any real evidence'''''. |
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| | ===Size of its disc=== | | ===Size of its disc=== |
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| − | The Moon is just far enough away from the Earth to appear the same size of the Sun. This creates a unique symmetry and phenomenal [[solar eclipse]]s. | + | The Moon is just far enough away from the Earth to appear at the same size as the Sun. This creates a unique symmetry and phenomenal [[solar eclipse]]s. |
| | In precise terms, the ratio of the apparent diameter of the Moon to that of the Sun is on average 0.97<ref name="creationresearch.org">Faulkner, Danny R. (June 1998). [https://crs-alchemy-attachments.s3.amazonaws.com/uploads/pdf/crsq-1998-volume-35-number-1.pdf "The angular size of the moon and other planetary satellites: An argument for design".] ''Creation Research Society Quarterly'' (St. Joseph, MO: Creation Research Society), vol. 35, no. 1, pp. 23-6.</ref> with a variation (due almost entirely to the [[orbital eccentricity|eccentricity]] of the Moon's orbit) of roughly ±0.05.<ref>Walker, John (May 1997). [http://www.fourmilab.ch/earthview/moon_ap_per.html "Inconstant moon: the moon at apogee and perigee"]. Fourmilab Switzerland website.</ref> | | In precise terms, the ratio of the apparent diameter of the Moon to that of the Sun is on average 0.97<ref name="creationresearch.org">Faulkner, Danny R. (June 1998). [https://crs-alchemy-attachments.s3.amazonaws.com/uploads/pdf/crsq-1998-volume-35-number-1.pdf "The angular size of the moon and other planetary satellites: An argument for design".] ''Creation Research Society Quarterly'' (St. Joseph, MO: Creation Research Society), vol. 35, no. 1, pp. 23-6.</ref> with a variation (due almost entirely to the [[orbital eccentricity|eccentricity]] of the Moon's orbit) of roughly ±0.05.<ref>Walker, John (May 1997). [http://www.fourmilab.ch/earthview/moon_ap_per.html "Inconstant moon: the moon at apogee and perigee"]. Fourmilab Switzerland website.</ref> |
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| | Of the known satellites in the [[Solar System]], only three others exhibit the phenomenon of being close in apparent size to the Sun when viewed from their parent planet. These are [[Saturn]]'s moons Prometheus and Epimetheus (with average diameter ratios of 1.03 and 0.95) and [[Uranus]]'s Cordelia (1.08).<ref name="creationresearch.org"/> Given the figure of approximately 170 known planetary satellites in the Solar System (though the figure regularly increases with new discoveries), this gives as an [[Probability|empirical probability]] for the phenomenon of 4/170 or 2.4%, which is consistent with the theoretical figure. | | Of the known satellites in the [[Solar System]], only three others exhibit the phenomenon of being close in apparent size to the Sun when viewed from their parent planet. These are [[Saturn]]'s moons Prometheus and Epimetheus (with average diameter ratios of 1.03 and 0.95) and [[Uranus]]'s Cordelia (1.08).<ref name="creationresearch.org"/> Given the figure of approximately 170 known planetary satellites in the Solar System (though the figure regularly increases with new discoveries), this gives as an [[Probability|empirical probability]] for the phenomenon of 4/170 or 2.4%, which is consistent with the theoretical figure. |
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| − | It should be noted, however, that by virtue of the planets' distance form the Sun, these eclipses would appear very small in the sky, and would be nothing as spectacular as a total solar eclipse on Earth. | + | It should be noted, however, that by virtue of the planets' distance from the Sun, these eclipses would appear very small in the sky, and would be nothing as spectacular as a total solar eclipse on Earth. |
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| | ===Rotation and revolution=== | | ===Rotation and revolution=== |
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| − | The Moon presents the same side to Earth at all times. That means that the rotation of the Earth offsets the separate effects of lunar revolution. Physical explanations rely on [[tidal locking]], asserting that tidal forces on Earth caused a bulge on the Moon, thereby creating a drag on the rotation of the Moon until the same side always faced the Earth.<ref group=note>The same theory suggested that the planet [[Mercury]] had a similar locked rotation due to gravitational forces from the sun, such that the same side of Mercury always faces the sun. In fact, that is false. [[Mercury]]'s tidal locking is incomplete and it does not always present the same face to the sun.</ref> In fact, current tidal forces exerted by the Earth on the Moon cannot account fully for its bulge or egg shape.<ref>"[http://physics.fortlewis.edu/Astronomy/astronomy%20today/CHAISSON/AT308/HTML/AT30803.HTM Chapter 8, Section 3: The Rotation of the Moon]," "Astronomy Today", Department of Physics, Fort Lewis College, Durango, [[Colorado|CO]]. Accessed February 18, 2008</ref> | + | The Moon presents the same side to Earth at all times. That means that the rotation of the Earth offsets the separate effects of the lunar revolution. Physical explanations rely on [[tidal locking]], asserting that tidal forces on Earth caused a bulge on the Moon, thereby creating a drag on the rotation of the Moon until the same side always faced the Earth.<ref group=note>The same theory suggested that the planet [[Mercury]] had a similar locked rotation due to gravitational forces from the sun, such that the same side of Mercury always faces the sun. In fact, that is false. [[Mercury]]'s tidal locking is incomplete and it does not always present the same face to the sun.</ref> In fact, current tidal forces exerted by the Earth on the Moon cannot account fully for its bulge or egg shape.<ref>"[http://physics.fortlewis.edu/Astronomy/astronomy%20today/CHAISSON/AT308/HTML/AT30803.HTM Chapter 8, Section 3: The Rotation of the Moon]," "Astronomy Today", Department of Physics, Fort Lewis College, Durango, [[Colorado|CO]]. Accessed February 18, 2008</ref> |
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| | ===Lunar origin theories=== | | ===Lunar origin theories=== |
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| | ===Rate of recession=== | | ===Rate of recession=== |
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| − | The Moon currently recedes from the Earth at a rate of 1.5 inches (3.8 cm) per year<ref>NASA [http://sunearth.gsfc.nasa.gov/eclipse/SEhelp/ApolloLaser.html Measuring the Moon's Distance], ''LPI Bulletin'', No. 72, August, 1994.</ref> and is believed by [[atheist]]ic scientists to be 4.6 billion years old,<ref>NASA, [http://history.nasa.gov/SP-350/ch-15-2.html Apollo Expeditions to the Moon], Chapter 15.2.</ref> but that is contradicted by an extrapolation backwards in time using its observed rate of recession. | + | The Moon currently recedes from the Earth at a rate of 1.5 inches (3.8 cm) per year<ref>NASA [http://sunearth.gsfc.nasa.gov/eclipse/SEhelp/ApolloLaser.html Measuring the Moon's Distance], ''LPI Bulletin'', No. 72, August 1994.</ref> and is believed by [[atheist]]ic scientists to be 4.6 billion years old,<ref>NASA, [http://history.nasa.gov/SP-350/ch-15-2.html Apollo Expeditions to the Moon], Chapter 15.2.</ref> but that is contradicted by an extrapolation backward in time using its observed rate of recession. |
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| − | The Moon could never have been closer than about 11,000 miles, or it would have been broken up by tidal forces.<ref name="js">Sarfati, Jonathan (September 1998). [http://www.creationontheweb.com/content/view/764/ "The moon: the light that rules the night".] ''Creation Ex Nihilo'' (Brisbane, QL, Australia: Answers in Genesis), vol. 20, no. 4, pp. 36–9. Reprinted at Creation.com website.</ref> If the rate of recession stayed constant at 3.8 cm per year, it would take 9.6 billion years for the lunar distance to migrate from 11,000 miles to the present distance of about 240,000 miles. However, a further principle would be needed to show the rate of recession would have been constant over the hypothetical 9.6-billion-year time period. | + | The Moon could never have been closer than about 11,000 miles, or it would have been broken up by tidal forces.<ref name="js">Sarfati, Jonathan (September 1998). [http://www.creationontheweb.com/content/view/764/ "The moon: the light that rules the night".] ''Creation Ex Nihilo'' (Brisbane, QL, Australia: Answers in Genesis), vol. 20, no. 4, pp. 36–9. Reprinted at Creation.com website.</ref> If the rate of recession stayed constant at 3.8 cm per year, it would take 9.6 billion years for the lunar distance to migrate from 11,000 miles to the present distance of about 240,000 miles. However, a further principle would be needed to show the rate of recession would have been constant over the hypothetical 9.6-billion-year period. |
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| | ===Impact craters=== | | ===Impact craters=== |
| − | Astronomers assume that crater impacts are a reliable indicator of the age of a celestial body. True to the form and principles of [[uniformitarianism]] (as applied to [[astronomy]] rather than to [[geology]]), any such estimation relies upon uniform constants and weather/erosion trends. Recent research into crater impacts on the moon suggests that many of the assumptions previously made are unwarranted. Bonnie Buratti of NASA's Jet Propulsion Laboratory has asserted that space weathering "takes place very rapidly on the Moon."<ref>David, Leonard. "[http://www.space.com/missionlaunches/lunar_impact_021214.html Lunar Crash of 1953: Impact Crater Identified]." <http://www.space.com>, December 14, 2002. Accessed January 16, 2008.</ref> Peter Brown of the University of Western Ontario insists that there is no absolute criteria for the dating of craters.<ref>Hecht, Jeff. "[http://www.newscientist.com/article.ns?id=dn3242 New crater revives Moon mystery]." <http://www.newscientist.com>, January 11, 2003. Accessed January 16, 2008.</ref> | + | Astronomers assume that crater impacts are a reliable indicator of the age of a celestial body. True to the form and principles of [[uniformitarianism]] (as applied to [[astronomy]] rather than to [[geology]]), any such estimation relies upon uniform constants and weather/erosion trends. Recent research into crater impacts on the moon suggests that many of the assumptions previously made are unwarranted. Bonnie Buratti of NASA's Jet Propulsion Laboratory has asserted that space weathering "takes place very rapidly on the Moon."<ref>David, Leonard. "[http://www.space.com/missionlaunches/lunar_impact_021214.html Lunar Crash of 1953: Impact Crater Identified]." <http://www.space.com>, December 14, 2002. Accessed January 16, 2008.</ref> Peter Brown of the University of Western Ontario insists that there are no absolute criteria for the dating of craters.<ref>Hecht, Jeff. "[http://www.newscientist.com/article.ns?id=dn3242 New crater revives Moon mystery]." <http://www.newscientist.com>, January 11, 2003. Accessed January 16, 2008.</ref> |
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| | ===Creationist models=== | | ===Creationist models=== |
| − | Danny Faulkner of the [[Institute for Creation Research]] has observed that many of the lunar maria contain ''ghost craters'', or craters that the lava flow that produced the maria seem to have filled only partially. In the [[deep time]] scale required by [[uniformitarianism]], the ghost craters are the result of impacts that occurred as much as half a gigayear before the crust-fracturing impacts that caused the lava flows.<ref name=Henderson>Henderson, Thomas H. "[http://www.hal-pc.org/~tom/HeavyCratering.html Do heavily cratered planets and moons demand an old age for the solar system]?" ''Tom Henderson's Creation Resources'', July 25, 2003. Accessed March 25, 2008.</ref> This is not a reasonable assumption, because any impact strong enough to crack the crust should have obliterated any craters previously extant. Faulkner thus concludes that the impacts that formed the ghost craters, and those that let loose the lava flows that formed the maria, occurred within days of one another<ref name=Faulkner1>Faulkner, Danny. "[https://www.icr.org/research/index/researchp_df_r01/ The Current State of Creation Astronomy]." ''Proceedings of the Fourth International Conference on Creationism,'' Creation Science Fellowship, Pittsburgh, pp. 201–216, August 3–8, 1998. Hosted at ''[[Institute for Creation Research]].'' Accessed March 25, 2008.</ref> and were probably part of at least one system-wide catastrophe involving a narrow stream of meteoroids and/or comets that delivered a concentrated bombardment of the Earth and Moon in a short interval.<ref name=Faulkner2>Faulkner, Danny. "[http://creationontheweb.com/content/view/1637 A Biblically-based cratering theory]." ''Technical Journal'' (now ''Journal of Creation''), 13(1):100-104, April 1999.</ref> | + | Danny Faulkner of the [[Institute for Creation Research]] has observed that many of the lunar maria contain ''ghost craters'', or craters that the lava flow that produced the maria seems to have filled only partially. In the [[deep time]] scale required by [[uniformitarianism]], the ghost craters are the result of impacts that occurred as much as half a gigayear before the crust-fracturing impacts that caused the lava flows.<ref name=Henderson>Henderson, Thomas H. "[http://www.hal-pc.org/~tom/HeavyCratering.html Do heavily cratered planets and moons demand an old age for the solar system]?" ''Tom Henderson's Creation Resources'', July 25, 2003. Accessed March 25, 2008.</ref> This is not a reasonable assumption, because any impact strong enough to crack the crust should have obliterated any craters previously extant. Faulkner thus concludes that the impacts that formed the ghost craters, and those that let loose the lava flows that formed the maria, occurred within days of one another<ref name=Faulkner1>Faulkner, Danny. "[https://www.icr.org/research/index/researchp_df_r01/ The Current State of Creation Astronomy]." ''Proceedings of the Fourth International Conference on Creationism,'' Creation Science Fellowship, Pittsburgh, pp. 201–216, August 3–8, 1998. Hosted at ''[[Institute for Creation Research]].'' Accessed March 25, 2008.</ref> and were probably part of at least one system-wide catastrophe involving a narrow stream of meteoroids and/or comets that delivered a concentrated bombardment of the Earth and Moon in a short interval.<ref name=Faulkner2>Faulkner, Danny. "[http://creationontheweb.com/content/view/1637 A Biblically-based cratering theory]." ''Technical Journal'' (now ''Journal of Creation''), 13(1):100-104, April 1999.</ref> |
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| − | Faulkner assumes that this system-wide catastrophe occurred during the year of the [[Great Flood]]. But in 1984, Russell Humphreys, then at the Sandia National Laboratories, developed evidence suggesting different dates entirely. Specifically, the [[Project Apollo]] exploration teams brought back many samples of [[basalt]] (an [[igneous rock]]) and [[brecchia]] (pulverized meteor-impact remains). Geologists analyzed both types of samples and found evidence that each type of rock had once been in a magnetic field far more powerful than that which the Moon has today. Using his model for the creation and decay of magnetic fields,<ref name=Humphreys/> Humphreys determined that the basalt had been laid down about 370 years after creation, and the brecchia had been laid down 1840 years after creation, or about 190 years after the Flood.<ref name=Humphreys2 group=note>Humphreys reasoned that the higher the magnetic dipole moment of the samples, the earlier in lunar history they were formed.</ref> These findings clearly suggest that the Moon, and presumably all other bodies in the solar system, have been subject to two separate system-wide bombardments, one occurring in the second or third generation after the [[fall of man]] and the other occurring well after the Flood. | + | Faulkner assumes that this system-wide catastrophe occurred during the year of the [[Great Flood]]. But in 1984, Russell Humphreys, then at the Sandia National Laboratories, developed evidence suggesting different dates entirely. Specifically, the [[Project Apollo]] exploration teams brought back many samples of [[basalt]] (an [[igneous rock]]) and [[brecchia]] (pulverized meteor-impact remains). Geologists analyzed both types of samples and found evidence that each type of rock had once been in a magnetic field far more powerful than that which the Moon has today. Using his model for the creation and decay of magnetic fields,<ref name=Humphreys/> Humphreys determined that the basalt had been laid down about 370 years after creation, and the breccia had been laid down 1840 years after creation, or about 190 years after the Flood.<ref name=Humphreys2 group=note>Humphreys reasoned that the higher the magnetic dipole moment of the samples, the earlier in lunar history they were formed.</ref> These findings clearly suggest that the Moon, and presumably all other bodies in the solar system, have been subject to two separate system-wide bombardments, one occurring in the second or third generation after the [[fall of man]] and the other occurring well after the Flood. |
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| | ==Tides== | | ==Tides== |
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| − | The gravitational force of the Moon causes the ocean [[tides]]; these tidal forces have other effects as well. These tidal forces have the effect of creating resistance which slows down the rotation of both objects. In the case of the Earth, the result is that the Earth's rotation slows on the order of one millisecond per century. The Moon's rotation is locked in to its period of revolution, and the same side of the Moon always faces the Earth. | + | The gravitational force of the Moon causes the ocean [[tides]]; these tidal forces have other effects as well. These tidal forces have the effect of creating resistance which slows down the rotation of both objects. In the case of the Earth, the result is that the Earth's rotation slows on the order of one millisecond per century. The Moon's rotation is locked into its period of revolution, and the same side of the Moon always faces the Earth. |
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| | ==The "dark" or far side== | | ==The "dark" or far side== |
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| | The phrase "the ''dark'' side of the Moon" is inaccurate because the Moon does rotate relative to the Sun, with the same period as its period of revolution, once every 29 days. Our view of the Moon from the Earth always shows the same side of the Moon, with the same markings and features. When the Moon is full, the entire side that faces us is experiencing lunar "day" and is lit by the Sun. Two weeks later, when the Moon is new, the side that faces us is experiencing solar "night" and is unlit (and virtually invisible). | | The phrase "the ''dark'' side of the Moon" is inaccurate because the Moon does rotate relative to the Sun, with the same period as its period of revolution, once every 29 days. Our view of the Moon from the Earth always shows the same side of the Moon, with the same markings and features. When the Moon is full, the entire side that faces us is experiencing lunar "day" and is lit by the Sun. Two weeks later, when the Moon is new, the side that faces us is experiencing solar "night" and is unlit (and virtually invisible). |
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| − | The far side of the moon is far more heavily cratered than the near, and the predominant type of cratering is consistent with brecchia-forming meteor impact. This would suggest that the far side suffered its bombardment in the latter of the two catastrophes that Humphreys suggests that the Moon has suffered. | + | The far side of the moon is far more heavily cratered than the near, and the predominant type of cratering is consistent with breccia-forming meteor impact. This would suggest that the far side suffered its bombardment in the latter of the two catastrophes that Humphreys suggests that the Moon has suffered. |
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| | Due to a slight "wobble" in the lunar motion called ''libration,'' we actually see a little bit more than half of the Moon's surface; sometimes it is turned a bit one way and sometimes the other. However, nobody had any idea of what the far side of the Moon looked like until 1959, when a Soviet satellite photographed it and relayed pictures back. | | Due to a slight "wobble" in the lunar motion called ''libration,'' we actually see a little bit more than half of the Moon's surface; sometimes it is turned a bit one way and sometimes the other. However, nobody had any idea of what the far side of the Moon looked like until 1959, when a Soviet satellite photographed it and relayed pictures back. |
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| | ::I fear we'll come to harm." | | ::I fear we'll come to harm." |
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| − | The effect known as "the old Moon in the new Moon's arms" can often be seen when the Moon is a narrow [[crescent]]. Within the intensely bright crescent, a dim and mysterious view of the entire circular moon is seen. The effect is also known as ''earthshine'' because it is light from the Sun reflected off the Earth to the Moon and back that lights up the darker portion of the Moon. The bright crescent is lit by the Sun and is in full daylight. The rest of the Moon is not lit by the Sun; but an [[astronaut]] standing in this area would see a "full Earth" dominating the nighttime sky, lighting it up by its earthshine. The brightness of Earthshine, and hence the visibility of the old Moon in the new Moon's arms, varies. When the Earth is covered with clouds, or when there is a lot of snow-pack on the side of the Earth facing the Moon, the Earth is a white and bright and the Earthshine is intense. When the Earth looks like a "big, blue marble," it is less intense. | + | The effect known as "the old Moon in the new Moon's arms" can often be seen when the Moon is a narrow [[crescent]]. Within the intensely bright crescent, a dim and mysterious view of the entire circular moon is seen. The effect is also known as ''earthshine'' because it is light from the Sun reflected off the Earth to the Moon and back that lights up the darker portion of the Moon. The bright crescent is lit by the Sun and is in full daylight. The rest of the Moon is not lit by the Sun; but an [[astronaut]] standing in this area would see a "full Earth" dominating the nighttime sky, lighting it up by its earthshine. The brightness of Earthshine, and hence the visibility of the old Moon in the new Moon's arms, varies. When the Earth is covered with clouds, or when there is a lot of snow-pack on the side of the Earth facing the Moon, the Earth is white and bright and the Earthshine is intense. When the Earth looks like a "big, blue marble," it is less intense. |
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| | ==Lunar calendars== | | ==Lunar calendars== |
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| | Rocks on the Moon are magnetized, yet there is no magnetic field there today. In one new proposal, researchers at the University of California have suggested that the moon's solid-rock middle layer, called its mantle, stirs up its liquid iron core. The researchers believe this happens because the moon's core and its mantle rotate around slightly different axes, and the boundary between them is not quite spherical. | | Rocks on the Moon are magnetized, yet there is no magnetic field there today. In one new proposal, researchers at the University of California have suggested that the moon's solid-rock middle layer, called its mantle, stirs up its liquid iron core. The researchers believe this happens because the moon's core and its mantle rotate around slightly different axes, and the boundary between them is not quite spherical. |
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| − | The strength of this stirring is determined by the angle between the core and the mantle, and the distance between the Earth and the moon, because the tidal forces from the Earth causes the moon's mantle to rotate differently than the core. | + | The strength of this stirring is determined by the angle between the core and the mantle, and the distance between the Earth and the moon, because the tidal forces from the Earth cause the moon's mantle to rotate differently than the core. |
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| − | This model would explain why the moon no longer has a magnetic field. Since the angle between the mantle and the core has narrowed over time, while the distance between the moon and the Earth has widened, this has caused the tidal forces to steadily decrease. While these forces used to be enough to generate a dynamo inside the moon, they aren't anymore. | + | This model would explain why the moon no longer has a magnetic field. Since the angle between the mantle and the core has narrowed over time, while the distance between the moon and the Earth has widened, this has caused the tidal forces to decrease steadily. While these forces used to be enough to generate a dynamo inside the moon, they aren't anymore. |
| | <ref>Moskowitz, Clara (2011). [https://www.csmonitor.com/Science/2011/1109/Have-scientists-finally-solved-the-mystery-of-the-magnetic-moon "Have scientists finally solved the mystery of the magnetic moon?"] ''Christian Science Monitor'' website.</ref> | | <ref>Moskowitz, Clara (2011). [https://www.csmonitor.com/Science/2011/1109/Have-scientists-finally-solved-the-mystery-of-the-magnetic-moon "Have scientists finally solved the mystery of the magnetic moon?"] ''Christian Science Monitor'' website.</ref> |
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| | |Eris || 1 || Dysnomia | | |Eris || 1 || Dysnomia |
| | |} | | |} |
| − | There are at least 182 natural moons known to exist in our solar system, counting those which are in orbit of dwarf planets.<ref>Multiple references: | + | There are at least 182 natural moons known to exist in our solar system, counting those which are in the orbit of dwarf planets.<ref>Multiple references: |
| | *https://windows2universe.org/our_solar_system/moons_table.html (Retrieved April 9, 2019) | | *https://windows2universe.org/our_solar_system/moons_table.html (Retrieved April 9, 2019) |
| | *https://www.universetoday.com/15516/how-many-moons-are-in-the-solar-system/ (Retrieved April 9, 2019) | | *https://www.universetoday.com/15516/how-many-moons-are-in-the-solar-system/ (Retrieved April 9, 2019) |