Earth Without A Moon Isn't Earth At All
This document was uploaded by user and they confirmed that they have the permission to share it. If you are author or own the copyright of this book, please report to us by using this DMCA report form. Report DMCA
Overview
Download & View Earth Without A Moon Isn't Earth At All as PDF for free.
More details
- Words: 1,843
- Pages: 7
Earth without a Moon isn't Earth at all
Kris McNeeley Nick Koker
The Moon of our planet, Earth, isn't something that most people think about very often. It is the closest celestial body to us, the only one a human has walked on, and is the closest moon in size relative to its mother planet. Most people know these things but how many people know how the Moon came to be and how its presence affects Earth? It's easy to overlook and take the Moon for granted due to it being so far away but, like the much further Sun, the Moon appears in our sky on a daily basis for a considerable amount of time. With this in mind, just about anyone can tell you the important effects the Sun has on our planet. Also, in its own ways the Moon is arguably just as necessary for life to exist on Earth as the Sun. So why is it that the same number of people won't be able to answer the same question about the Moon? Since the effects of the Sun are common knowledge, for the most part, then it would be easy to identify what would happen without it. The loss of the Sun would indeed be a terrifying idea but I suggest thinking about closer to home and what if we had no Moon? The giant impact hypothesis is the currently favored scientific hypothesis for the formation of the Moon. The idea here is that an object about the size of Mars(called Theia) struck proto-Earth at an oblique angle. When this occurred the iron core of Theia is presumed to have sunk into young Earth's core then most of Theia's mantle and part of the Earth's crust and mantle were ejected into orbit around the Earth. In some time possibly as short as a month or long as a century, the debris coalesced into the Moon. The “late heavy bombardment” of high meteoric activity occurred about 500 million years later and while the Earth was struck by small celestial bodies, more debris was ejected to the Moon. If this theory is correct it means the history of the Moon almost dates back just as long as the Earth itself. More importantly,
this theory makes it difficult to envision what the Earth, as we know it, would be like without the Moon. One of the biggest effects the Moon has on Earth are tidal forces. These are a secondary effect of gravity in which two sides exert gravitational forces on each other. There are two types of tides; spring and neap. Spring tides occur when the Earth, Moon, and Sun are aligned and of the combined gravitational pull of the Moon and the Sun result in especially strong tides. High spring tides are very high and low spring tides are very low. Neap tides have a smaller difference of high and low tides because they occur when the Moon and Sun are perpendicular to each other in respect to the Earth which causes a weaker force than the spring tides. Tidal forces occur because water is always moving and the Earth is not able to hold onto it. The Sun also creates a tidal force on Earth but it is only 46 percent that of the Moon so the Moon is the single most important factor in creating tides. So without the Moon our tides would still exist but they wouldn't be near as powerful as they are now. Some scientists even suggest that ocean tides were key to mixing up the “primordial soup” that is theorized to have been the beginning of life in a warm pond or ocean from nonliving matter. So without the Moon it's possible that life may have never even begun on Earth. Even considering that solar tides would indeed be enough to begin life, it's possible that aspects of evolution would have been distorted and perhaps turn out completely different then how they did today. For example, a tidal force can create an area that is always wet but not always covered in water. This may have provided an important environmental stress that aided in the evolution of sea plants and fish to land plants and animals. If life did indeed begin in water then our Moon was a vital part of the process due to it being the biggest factor in the way our tides move.
Tidal forces also cause significant heating and dissipation of energy to take place. Part of this energy heats the Earth and part of it is dissipating by forcing the Moon to move away from the Earth over time. It has been proposed that the Moon may have helped trigger convection on Earth that resulted in the plate tectonics that drag our crust and then pulls it down into the mantle to be recycled. Without plate tectonics, the Earth would still bear the scars of colliding objects during it's formation such as in the Moon's case where there are craters littered over the surface through the lifespan. Scientists believe plate tectonics are necessary to stabilize temperatures enough for life because the constant crust recycling keeps carbon dioxide levels in the atmosphere stable by removing the gas through weathering and later returning it through volcanic activity. So, even long before the conditions for life were present, the Moon was needed to even begin shaping the planet for these conditions. Tides are not the only thing affected by the force exerted from the Moon. The Moon is also a stabilizing factor for the rotation axis of the Earth. Some planets, such as Mars, may wobble on their axis due to the gravitational influence of the other planets in the solar system but due to the size and distance of our Moon the Earth's axis stays stable in the same direction. Because of this, Earth had much less climate change then if it were alone which allowed for multi-cellular organisms that cannot survive drastic climate changes. Again we are seeing some biological and evolutionary influences of the Moon. The Moon can completely change the aspects of evolution such as the effect on the way moonlight-sensitive mammals developed night vision that is effective in partial illumination, due to them being most active at this time, but makes them more vulnerable to predators If the Earth's axis was perpendicular to the plane of the solar system, the collision of
Theia may have knocked the Earth slightly off that axis which was stabilized by the forming Moon to the 23.5 degree tilt it's on now. Had the axis remained perpendicular, sunlight would strike the Earth at a fixed angle all the time. This axis would have caused much different seasons we know today and could have catastrophically disrupted the developing biospheres. The way our seasons formed was a direct result of the tilt that the Moon keeps us on. Rather than being something that occurs at different times of the year, all seasons would occur all the time at different latitudes. Just as it tends to get warmer as you get closer to the equator, the summer “season” would occur as a belt around the equator with spring and fall being the midlatitudes and winter being the extreme latitudes. Perhaps the most important effect the Moon has had on the way the Earth is today was how it actually aided to the study of Astronomy. Lunar phases were studied to determine how far away the Moon is from Earth, the size of the Earth, and our distance from the Sun. The idea that the Earth was the center of the universe was done away by the study of lunar and solar eclipses that, when accurately predicted, showed the way the Moon moves and how the Sun does not. With the knowledge of lunar and solar activity came one of Astronomy's earliest, and most vital, result; the calendar. Most of the oldest calendars were lunar calendars based on the Moon cycle. Over time solar patterns were integrated into calendars to attribute for the annual events that had nothing to do with the phases of the Moon. The Sun was used to account for the calendar year and the Moon was used to account for the days within that year. Knowing how many days are in a year and how the Moon cycle works, months were then devised to coincide with that cycle and to fit into the 365 ¼ solar year. Not only has the Moon provided so much to the existence on Earth, but there are new
ways to utilize the Moon and how it works to better our planet. One of these is these theories is the use of tidal energy as a renewable energy source based on lunar gravitation over solar radiation. Tidal mills have been found to date back to the 12th century so the idea of exploiting the energy of the tides isn't new. Today, this idea has lead to proposed tidal energy devices that are completely submerged underwater, such as a modern looking windmill, that aim to convert tidal streams into power. The problem with this is the cost of needing to build in a difficult saltwater environment and the limited energy output allowed by the twice-daily ebb and flow of tides but if there is ever a more convenient way to utilize these techniques, the Moon could be the answer to Earth's fleeting energy sources. So what would the Earth be like if it did not have a Moon? The result would basically be a completely different planet then the one we live on today. The Earth may have begun its life on a different axis, resulting in distorted applications of seasons and significant effects on weather systems and circulation patterns. Even if the Earth began on its present axis there would be nothing to stabilize that axis. Convection may not have begun and the crust of the Earth would not be recycled or get rid of volatile gases in the atmosphere. There may have not been enough tidal force from the Sun alone to allow the conditions for life to begin and the lacking lunar force would be the loss of a heat source for the Earth. The entire evolutionary process, if possible, would have revolved around different conditions thus different results. The most important aspect of our Moon is the way it was used in the development of Astronomy. If life on Earth were possible without the Moon it would be vastly different then it is today. Our closest neighbor is possibly the biggest contributing factor to how Earth turned out.
Foing, Bernard. “If we had no Moon.” Astrobio. Oct. 2007. http://www.astrobio.net/index.php?option=com_retrospection&task=detail&id=2507 Cooley, Keith. “Moon Tides: How the Affects Ocean Tides.” 2002. http://home.hiwaay.net/~krcool/Astro/moon/moontides/ Odenwald, Dr. Sten. “What would happen if the Earth did not have the Moon?” Astronomycafe. 1997. http://www.astronomycafe.net/qadir/q106.html Clark, R.H. “Tidal Energy.” Canadianencyclopedia. http://www.thecanadianencyclopedia.com/index.cfm? PgNm=TCE&Params=A1ARTA0008003#ArticleContents Fielder, G. Geology and Physics of the Moon. New York: Elsevier, 1971 “History of the Calendar.” infoplease. 2007 http://www.infoplease.com/ipa/A0002061.html North, Gerald. Observing the Moon. United Kingdom: University Press, 2000
Kris McNeeley Nick Koker
The Moon of our planet, Earth, isn't something that most people think about very often. It is the closest celestial body to us, the only one a human has walked on, and is the closest moon in size relative to its mother planet. Most people know these things but how many people know how the Moon came to be and how its presence affects Earth? It's easy to overlook and take the Moon for granted due to it being so far away but, like the much further Sun, the Moon appears in our sky on a daily basis for a considerable amount of time. With this in mind, just about anyone can tell you the important effects the Sun has on our planet. Also, in its own ways the Moon is arguably just as necessary for life to exist on Earth as the Sun. So why is it that the same number of people won't be able to answer the same question about the Moon? Since the effects of the Sun are common knowledge, for the most part, then it would be easy to identify what would happen without it. The loss of the Sun would indeed be a terrifying idea but I suggest thinking about closer to home and what if we had no Moon? The giant impact hypothesis is the currently favored scientific hypothesis for the formation of the Moon. The idea here is that an object about the size of Mars(called Theia) struck proto-Earth at an oblique angle. When this occurred the iron core of Theia is presumed to have sunk into young Earth's core then most of Theia's mantle and part of the Earth's crust and mantle were ejected into orbit around the Earth. In some time possibly as short as a month or long as a century, the debris coalesced into the Moon. The “late heavy bombardment” of high meteoric activity occurred about 500 million years later and while the Earth was struck by small celestial bodies, more debris was ejected to the Moon. If this theory is correct it means the history of the Moon almost dates back just as long as the Earth itself. More importantly,
this theory makes it difficult to envision what the Earth, as we know it, would be like without the Moon. One of the biggest effects the Moon has on Earth are tidal forces. These are a secondary effect of gravity in which two sides exert gravitational forces on each other. There are two types of tides; spring and neap. Spring tides occur when the Earth, Moon, and Sun are aligned and of the combined gravitational pull of the Moon and the Sun result in especially strong tides. High spring tides are very high and low spring tides are very low. Neap tides have a smaller difference of high and low tides because they occur when the Moon and Sun are perpendicular to each other in respect to the Earth which causes a weaker force than the spring tides. Tidal forces occur because water is always moving and the Earth is not able to hold onto it. The Sun also creates a tidal force on Earth but it is only 46 percent that of the Moon so the Moon is the single most important factor in creating tides. So without the Moon our tides would still exist but they wouldn't be near as powerful as they are now. Some scientists even suggest that ocean tides were key to mixing up the “primordial soup” that is theorized to have been the beginning of life in a warm pond or ocean from nonliving matter. So without the Moon it's possible that life may have never even begun on Earth. Even considering that solar tides would indeed be enough to begin life, it's possible that aspects of evolution would have been distorted and perhaps turn out completely different then how they did today. For example, a tidal force can create an area that is always wet but not always covered in water. This may have provided an important environmental stress that aided in the evolution of sea plants and fish to land plants and animals. If life did indeed begin in water then our Moon was a vital part of the process due to it being the biggest factor in the way our tides move.
Tidal forces also cause significant heating and dissipation of energy to take place. Part of this energy heats the Earth and part of it is dissipating by forcing the Moon to move away from the Earth over time. It has been proposed that the Moon may have helped trigger convection on Earth that resulted in the plate tectonics that drag our crust and then pulls it down into the mantle to be recycled. Without plate tectonics, the Earth would still bear the scars of colliding objects during it's formation such as in the Moon's case where there are craters littered over the surface through the lifespan. Scientists believe plate tectonics are necessary to stabilize temperatures enough for life because the constant crust recycling keeps carbon dioxide levels in the atmosphere stable by removing the gas through weathering and later returning it through volcanic activity. So, even long before the conditions for life were present, the Moon was needed to even begin shaping the planet for these conditions. Tides are not the only thing affected by the force exerted from the Moon. The Moon is also a stabilizing factor for the rotation axis of the Earth. Some planets, such as Mars, may wobble on their axis due to the gravitational influence of the other planets in the solar system but due to the size and distance of our Moon the Earth's axis stays stable in the same direction. Because of this, Earth had much less climate change then if it were alone which allowed for multi-cellular organisms that cannot survive drastic climate changes. Again we are seeing some biological and evolutionary influences of the Moon. The Moon can completely change the aspects of evolution such as the effect on the way moonlight-sensitive mammals developed night vision that is effective in partial illumination, due to them being most active at this time, but makes them more vulnerable to predators If the Earth's axis was perpendicular to the plane of the solar system, the collision of
Theia may have knocked the Earth slightly off that axis which was stabilized by the forming Moon to the 23.5 degree tilt it's on now. Had the axis remained perpendicular, sunlight would strike the Earth at a fixed angle all the time. This axis would have caused much different seasons we know today and could have catastrophically disrupted the developing biospheres. The way our seasons formed was a direct result of the tilt that the Moon keeps us on. Rather than being something that occurs at different times of the year, all seasons would occur all the time at different latitudes. Just as it tends to get warmer as you get closer to the equator, the summer “season” would occur as a belt around the equator with spring and fall being the midlatitudes and winter being the extreme latitudes. Perhaps the most important effect the Moon has had on the way the Earth is today was how it actually aided to the study of Astronomy. Lunar phases were studied to determine how far away the Moon is from Earth, the size of the Earth, and our distance from the Sun. The idea that the Earth was the center of the universe was done away by the study of lunar and solar eclipses that, when accurately predicted, showed the way the Moon moves and how the Sun does not. With the knowledge of lunar and solar activity came one of Astronomy's earliest, and most vital, result; the calendar. Most of the oldest calendars were lunar calendars based on the Moon cycle. Over time solar patterns were integrated into calendars to attribute for the annual events that had nothing to do with the phases of the Moon. The Sun was used to account for the calendar year and the Moon was used to account for the days within that year. Knowing how many days are in a year and how the Moon cycle works, months were then devised to coincide with that cycle and to fit into the 365 ¼ solar year. Not only has the Moon provided so much to the existence on Earth, but there are new
ways to utilize the Moon and how it works to better our planet. One of these is these theories is the use of tidal energy as a renewable energy source based on lunar gravitation over solar radiation. Tidal mills have been found to date back to the 12th century so the idea of exploiting the energy of the tides isn't new. Today, this idea has lead to proposed tidal energy devices that are completely submerged underwater, such as a modern looking windmill, that aim to convert tidal streams into power. The problem with this is the cost of needing to build in a difficult saltwater environment and the limited energy output allowed by the twice-daily ebb and flow of tides but if there is ever a more convenient way to utilize these techniques, the Moon could be the answer to Earth's fleeting energy sources. So what would the Earth be like if it did not have a Moon? The result would basically be a completely different planet then the one we live on today. The Earth may have begun its life on a different axis, resulting in distorted applications of seasons and significant effects on weather systems and circulation patterns. Even if the Earth began on its present axis there would be nothing to stabilize that axis. Convection may not have begun and the crust of the Earth would not be recycled or get rid of volatile gases in the atmosphere. There may have not been enough tidal force from the Sun alone to allow the conditions for life to begin and the lacking lunar force would be the loss of a heat source for the Earth. The entire evolutionary process, if possible, would have revolved around different conditions thus different results. The most important aspect of our Moon is the way it was used in the development of Astronomy. If life on Earth were possible without the Moon it would be vastly different then it is today. Our closest neighbor is possibly the biggest contributing factor to how Earth turned out.
Foing, Bernard. “If we had no Moon.” Astrobio. Oct. 2007. http://www.astrobio.net/index.php?option=com_retrospection&task=detail&id=2507 Cooley, Keith. “Moon Tides: How the Affects Ocean Tides.” 2002. http://home.hiwaay.net/~krcool/Astro/moon/moontides/ Odenwald, Dr. Sten. “What would happen if the Earth did not have the Moon?” Astronomycafe. 1997. http://www.astronomycafe.net/qadir/q106.html Clark, R.H. “Tidal Energy.” Canadianencyclopedia. http://www.thecanadianencyclopedia.com/index.cfm? PgNm=TCE&Params=A1ARTA0008003#ArticleContents Fielder, G. Geology and Physics of the Moon. New York: Elsevier, 1971 “History of the Calendar.” infoplease. 2007 http://www.infoplease.com/ipa/A0002061.html North, Gerald. Observing the Moon. United Kingdom: University Press, 2000
Related Documents
Earth Without A Moon Isn't Earth At All
June 2020 3
Earth And Moon
November 2019 12
Earth
October 2019 87
Earth
November 2019 80
Earth
November 2019 74