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"The Earth's curvature explains this phenomenon, as described in the diagram accompanying the photograph.
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"The Andes Mountains, 287 miles away, and although taller than the plane's altitude, lay below the sensible horizon, marked by the white horizontal line in the photograph," NASA officials wrote in a description of the flight. In December 1930, for example, Stevens snapped a photo looking westward while flying at an altitude of 21,000 feet (6,400 meters) above Villa Mercedes, Argentina. Similarly, from a great distance, the tops of tall objects like mountains are visible well before their bases.Īnd Earth's curvature is clearly apparent from high altitudes, as Capt. If you've ever watched a ship on the horizon, you've seen this for yourself. There are so many experiments, observations and demonstrations that have, time and time again, revealed the curve of the Earth.Īs objects recede from you, they begin to look smaller and slowly disappear in a very unique way: first their bottoms become hidden, and then their tops. To put it bluntly, we know more about the curvature of Earth than almost any other topic in the realm of physical science.
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