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Two Instruments That Make It All Happen

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There are two instruments aboard Landsat 9.

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OLI- 2 is all about light.

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Once in orbit, OLI-2 collects sunlight reflected off Earth’s surface.

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The light passes through a set of filters,

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to separate out nine specific wavelength bands,

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in visible and infrared frequencies.

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Each band provides different pieces of information about

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what is down on the surface.

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The second instrument aboard Landsat 9, called TIRS-2,

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collects thermal infrared wavelengths,

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or temperature signatures emitted by the Earth itself.

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