Modern World 16
1 There are a few theories about the origin of the moon. The most widely accepted one was first proposed by George Darwin, the son of the famous Charles Darwin. It is known as “The Giant Impact Theory”. According to Darwin’s theory, the moon was the product of an impact between the Earth and a large object the size of the planet Mars which occurred about 4.5 billion years ago. The fragments from this collision came together and eventually formed our moon over about a year.
2 Although the moon is a lifeless rock, its presence is vital for life on Earth. There are about 150 moons in our solar system, but our moon is unique, at least for the Earth and its inhabitants. The moon is responsible for keeping the tilt of the Earth’s axis at an angle of about 23.5 degrees. This allows for the change of seasons on the Earth and keeps our climate within limits that can support life. The sun also plays a role in the tilt of the Earth but it is responsible for only 30% of the tilt. Because it is 400 times farther away from us, its effect is insignificant when compared to that of the moon.
3 If the Earth depended only on the sun regulating its tilt, it probably would not be able to support life as we know it. Tsunamis would constantly destroy continents, since the seas would follow the gravitational pull of the sun. The Earth’s tilt would swing back and forth drastically from 15 to 75 degrees. Changes in climate would be so extreme that the Earth might go from an ice age to the tropics and back again every few hundred years. Adapting to such changes would require the evolution of totally different kinds of species, and humans would probably not be one of them. Put simply, the moon is nothing less than a stabilizer for the Earth and makes all life on this planet possible.
4 Although we tend to think of the moon being in a fixed orbit around the Earth, it is actually moving away from us at a rate of 3.8 centimeters per year, and this is affecting the length of our day. During the past 500 million years, the length of the Earth’s day has increased by about 10 percent. In about 2 billion years, the moon will be too far from the earth to stabilize its spin, which will eventually kill all life. In 5 billion years, our moon will fly away completely.
2 Although the moon is a lifeless rock, its presence is vital for life on Earth. There are about 150 moons in our solar system, but our moon is unique, at least for the Earth and its inhabitants. The moon is responsible for keeping the tilt of the Earth’s axis at an angle of about 23.5 degrees. This allows for the change of seasons on the Earth and keeps our climate within limits that can support life. The sun also plays a role in the tilt of the Earth but it is responsible for only 30% of the tilt. Because it is 400 times farther away from us, its effect is insignificant when compared to that of the moon.
3 If the Earth depended only on the sun regulating its tilt, it probably would not be able to support life as we know it. Tsunamis would constantly destroy continents, since the seas would follow the gravitational pull of the sun. The Earth’s tilt would swing back and forth drastically from 15 to 75 degrees. Changes in climate would be so extreme that the Earth might go from an ice age to the tropics and back again every few hundred years. Adapting to such changes would require the evolution of totally different kinds of species, and humans would probably not be one of them. Put simply, the moon is nothing less than a stabilizer for the Earth and makes all life on this planet possible.
4 Although we tend to think of the moon being in a fixed orbit around the Earth, it is actually moving away from us at a rate of 3.8 centimeters per year, and this is affecting the length of our day. During the past 500 million years, the length of the Earth’s day has increased by about 10 percent. In about 2 billion years, the moon will be too far from the earth to stabilize its spin, which will eventually kill all life. In 5 billion years, our moon will fly away completely.
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