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[Music]

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300 trillion or so that's the

3
00:00:09,080 --> 00:00:07,049
number of photons released with each

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laser shot from the

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atlas instrument sounds like a large number but when

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the photons sail through the atmosphere and

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bounce off the earth they scatter in

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all directions just like

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atlas light does  it only receives back

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those photons that reflect

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directly off the instrument about

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a dozen this number

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00:00:32,540 --> 00:00:30,390
is minuscule but atlas measures the time

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00:00:34,549 --> 00:00:32,550
it takes for photons to return

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very precisely allowing