The Earth's shape is a result of its spin, but why is it not a perfect sphere?

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In summary, the Earth is not a sphere because of its rotation and gravitational forces, which cause it to be an oblate spheroid shape. This was first theorized by Copernicus and later confirmed by Galileo through observations of Venus and analysis of its phases. The Earth's shape is influenced by its rotation around its own axis and its position on the planet, with equatorial regions experiencing more centrifugal force and resulting in a flattened shape. Without rotation, the Earth would be a perfect sphere.
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semc
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okay i know everyone knows Earth is not a sphere but why is that so?has it got to do with the spin?
btw,i was wondering how did galileo found out that sun is not in Earth orbit but the other way round in the past?

Thanks
 
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Copernicus (before galileo) found that the retrograde motions of planets are easily explained if all planets, including earth, revolved areound the Sun. Galileo made observations of Venus that showed phases just like the Moon has. Simple analysis proved that these phases can only be due to revolution around the Sun, and not the Earth.
 
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If we disregard the surface irregularities of the Earth that solid matter makes, the Earth is an oblate spheroid (a flattened sphere).
This shape is the natural one for an object revolving around its own axis.
Close to equator, the centrifugal effect works more strongly than close to the poles, thus when the centrifugal effects are balanced by the pull of gravity, the flattened shape is what you'll get.

With gravity alone and no revolution about any axis, you'd get a perfect sphere.
 

FAQ: The Earth's shape is a result of its spin, but why is it not a perfect sphere?

What evidence supports the idea that the Earth is not round?

There are several pieces of evidence that support the idea that the Earth is not perfectly spherical. For example, the Earth's shape is slightly flattened at the poles and bulging at the equator, which suggests an oblate spheroid shape. Additionally, satellite images and measurements of the Earth's curvature show slight variations in its roundness. Finally, the concept of gravity and how it affects the Earth's shape also supports the idea that it is not a perfect sphere.

How do scientists explain the misconception that the Earth is round?

The misconception that the Earth is round can be attributed to several factors, including early observations that suggested a spherical shape, religious beliefs and teachings, and the limitations of human perception. Additionally, the Earth appears to be round when viewed from a distance, which can further perpetuate the misconception.

What implications does the idea of the Earth not being round have on our understanding of the world?

The idea of the Earth not being round challenges traditional beliefs and theories about the universe and our place within it. It also opens up new avenues of scientific exploration and understanding, as well as prompts us to question our assumptions and biases.

How does the shape of the Earth impact our daily lives?

While the shape of the Earth may seem like a purely scientific concept, it actually has several practical implications in our daily lives. For example, the Earth's curvature affects how we navigate and travel, as well as how we communicate and use technology. It also plays a role in weather patterns and climate, which in turn impact agriculture and other industries.

What other evidence supports the idea of a non-round Earth?

In addition to the evidence discussed above, there are other scientific observations and theories that support the idea of the Earth not being perfectly round. These include the concept of plate tectonics and the Earth's dynamic geology, as well as the effects of the Moon's gravitational pull on the Earth's shape. Ultimately, the shape of the Earth is a complex and multifaceted topic that continues to be explored and studied by scientists around the world.

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