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♪Light Piano Music ♪

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Terra has consistently orbited Earth from pole to pole

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for over twenty years, collecting important data about Earth's systems.

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Crossing the equator at 10:30 am mean local time 

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allowed Terra's five instruments to collect consistent, simultaneous data,

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important to Earth's systems research and applications.

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In 2020, Terra completed its final inclination maneuver

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using some of its limited fuel supply, to maintain that crossing time.

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Since that final inclination maneuver, 

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Terra has continuously drifted to an earlier equatorial crossing time.

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By the Fall of 2022,

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Terra's crossing time will be earlier than 10:15 am.

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Then, Terra will be lowered to a new orbit 

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where it will be able to collect valuable data

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at an even earlier crossing time.

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As Terra's crossing time creeps earlier,

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small changes will be noticeable in Terra's data and imagery.

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Evidence in imagery of the earlier crossing time

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will be visible as longer shadows,

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especially in mountain landscapes.

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Like in these images of the Grant Range in Nevada.

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Meanwhile, as Terra moves closer to Earth

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the sensors' views will become narrower

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leading to slightly narrower swath widths.

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The effect will be most noticeable in ASTER imagery,

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but each of Terra's sensors will be affected.

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However, the impact on science is expected to be minimal.

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In fact,  some impacts could prove beneficial to some areas of research,

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like land morphology,

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surface temperature,

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and climate research.

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Terra's lengthy legacy of more than two decades of data

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will continue to contribute to meaningful research

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of Earth's Systems science for years to come.