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Roger Weller, geology instructor

by Jared Hill
Physical Geology
Fall 2007

The Moon

The Moon; where did it come from? How long has it been there?  What purpose does it serve? How does it affect life on earth? These are all question we should be asking ourselves everyday. Almost every day or night, it is there. Ever present, and always showing itself to us. Yet, many of us simply take it for granted and often forget to even acknowledge that it exists. Even for the few of us who take the time to study it and try to understand it, there are more questions than answers.



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For starters, there are many theories about where the moon came from. There is the Fission Theory, which suggests that the material that makes up the moon was once

part of the earth. There is the Capture Theory, which supposes that the moon formed somewhere in another solar system and was captured by the earth’s gravity and pulled into our orbit. Then there is the Condensation Theory, which explores the possibility that the earth and the moon condensed individually from the nebula that created our solar system. Perhaps the most widely accepted theory is the Giant Impactor Theory. This theory suggests that a small planet about the size of Mars hit earth a glancing blow early in our solar system’s life. The result was a massive ejection of heated material from both planets, which formed a disk of orbiting material. This material eventually started to stick together and became our moon.

“Giant Impactor Theory,”

So, regardless of what theory one chooses to believe, the question of how long the moon has been in existence is still there. The answer to this question varies greatly with each theory. However, if one chooses to accept the most popular theory, the Giant Impactor Theory, the Moon, or at least the material that eventually formed the Moon, has been there for about 4.5 million years. So the moon was up there long before we were here.



           Now that we have answered, or at least explored the theories on where the Moon came from and how long it has been here, we have to ask ourselves what purpose it serves. The one real obvious affect the Moon has on the earth is tidal activity. According to Patrick Moore, author of The Moon, the effects the Moon has on Earth’s oceans can be seen on a daily basis. “The Moon’s gravitational pull will be strongest on the closest hemisphere, causing the water to accelerate towards the Moon and heap up. Meanwhile, the water on the far side of the Earth will experience the weakest acceleration due to the Moon’s gravity and will therefore be ‘left behind’ as the Earth accelerates away from it, thus producing the second bulge” (Moore 10). As Moore stated in the previous quotation, the Moon’s orbit takes it around the Earth, and its gravitational pull causes the ocean waters to follow it, which creates the tidal flow. While there is no definite answer to what would happen if this tidal action did not occur, many people believe that the waters in the oceans would become stagnant and as a result sea life would be greatly altered.



          If we consider the fact that without the Moon and its intimate connection with earth, our oceans might be almost void of life, we can easily understand that this could have a catastrophic effect for life on earth. The ocean’s water may be undrinkable, but it really is the life-blood of human kind. Without the tidal effects of the Moon, so much of the life, or possibly even all the life that is currently on Earth, would likely cease to exist.

          Suppose the Moon simply went away and was no longer in existence.  For starters, there would be no tides. No tides mean no, or little, life in the tidal areas of the ocean.  


“Earth-Moon Tidal Pools,”

            If all the creatures living in the tidal areas of the oceans died off, the chemical and organic make-up of the ocean would be drastically altered. Ocean currents, which move cold and hot water throughout the Ocean, regulate the salinity, and help carry many sea creatures on long journeys, would likely stop. If this happened, animal feeding habits would be severely altered, the ocean creatures not living in the tidal areas would likely die because of the change in salinity and lack of traveling animals to feed on, the Glaciers would likely melt so sea levels could raise drastically. This in turn would have a tragic effect on mankind and many of our cities.

         So, in conclusion, next time you look into the sky, take a few seconds to see if the moon is still up there, because if it isn’t, you will probably be in for the experience of your life.

         It may hard to believe that what appears to be nothing more that a gray rock is greatly responsible for life, as we know it. While no one really knows for sure where the Moon came from, or how long it has been up there, the affects of the moon are felt every day, everywhere. It is an undoubtedly strong force for life here on earth.

Works Cited

Moore, Patrick. The Moon. Ed. Gilead Cooper. New York: Rand McNally: 1981.
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15 Nov. History of the Moon.…/     Earth_Moon/TidePools.jpg>