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Floating hundreds of miles from Earth,

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astronauts get a unique perspective of our planet.

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While they might recognize landmarks,

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space is the only place they can see the very edge of our planet’s atmosphere.

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From orbit particularly looking at the horizon,

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did bring to mind how thin the atmosphere is.

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It's like an onionskin around this great big ball of the earth.

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This uppermost layer of Earth’s atmosphere,

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the ionosphere, also overlaps with the very beginning of space.

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It’s the job of NASA’s new mission, GOLD -

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the Global-scale Observations of the Limb and Disk instrument -

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to study this region --

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a region that isn’t just for astronauts to explore,

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but that affects humans every day down on the ground.

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For one thing, this layer of the upper atmosphere helps protect us

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from harmful radiation and energy emanating from the Sun.

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But in our modern society, it does so much more.

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It affects the smartphone that sits in your pocket

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and the radio waves that guide our airplanes.

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The ionosphere is a crucial layer of the atmosphere

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through which our communications and GPS signals travel.

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And when this region changes, it impacts those communications signals.

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Changes can occur above this region from the Sun’s activity,

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also known as space weather.

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Changes can also occur below from Earth’s weather such as hurricanes and wind patterns.

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GOLD connects the dots between how space weather and Earth’s weather

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shape the upper reaches of the atmosphere.

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But this region isn’t easy to study.

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The ionosphere spans roughly 60 to 400 miles from Earth’s surface,

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which is too high for aircraft and scientific balloons

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and the lower regions are too low to easily study with satellites.

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What are attainable, however,

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are the swathes of red and green light shining out from the upper atmosphere.

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Formed when the Sun’s rays hit atmospheric molecules,

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this light named “airglow”, comes from green and red bands of glowing gas.

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Some of the airglow is invisible to our eyes,

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shining in infrared and ultraviolet light,

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which can only be seen with scientific instrumentation.

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Taking advantage of our planet’s natural glow is GOLD.

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The GOLD instrument, which is about the size of a mini fridge,

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is hitching a ride on a commercial communications satellite, SES-14.

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The satellite’s orbit lies 22,000 miles above Earth

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where it can record images in ultraviolet light to monitor changes in airglow across the globe.

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These images give information on the temperature, density, and composition of particles in the upper atmosphere.

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GOLD collects these observations faster than any mission has ever done before.

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It captures an image of Earth’s entire disk every 30 minutes,

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allowing scientists to see how the upper atmosphere evolves throughout the day.

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GOLD joins a host of missions studying the very nature of space --

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around Earth, the Sun, and planets.

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As NASA ventures farther and farther from home,

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knowing the nature of space itself

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is crucial for our journey to understand our solar system -- and beyond.

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