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As a Landsat satellite flies over the surface of the Earth

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the instruments aboard the satellite

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are able to view a swath 185 kilometers wide

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and collect images along that swath as the satellite proceeds

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through its orbit. The spacecraft travels at approximately

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4.7 miles per second. The satellite travels

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from north to south while it's over the sunlit portion of the Earth,

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and travels south to north over the dark side of the Earth.

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One orbit takes about 99 minutes, so that's about

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approximately 15 orbits in a 24 hour period.

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The orbit's maintained such that after

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16 days. the entire surface of the Earth has come

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within view of the Landsat instruments, while sunlit,

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and then on day 17 the first ground path

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is repeated. So we get to view the entire surface once every 16 days

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[beeping]