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Return to The History of Geodesy

Since the days of ancient mythology, scientists and philosophers have debated the shape of Earth. Since about 500 B.C., the idea that the Earth was a perfect sphere has dominated most scientific thinking, even though the concept of a flat Earth may have persisted in some regions for another millenium. Around the end of the 16th century, the idea that the Earth was a perfect sphere evolved into a radical new idea: that the Earth was an imperfect sphere. This new way of thinking was initially divided into two major schools of thought. One believed the Earth was egg-shaped (prolate). The other believed the Earth was flattened at the poles (oblate). The modern concept of a basically oblate Earth was demonstrated to be correct and has spawned many theoretical variations during the last hundred years as geodesy has advanced. Use the slider bar on the bottom of your browser to view the entire image.
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Evolving concept of the Earth

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