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Along the way from Earth to outer space,

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you pass through a busy intersection.

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Located between 50 and 400 miles above the Earth's surface

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this stretch of sky is known as the upper atmosphere.

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Here, spacecraft transit, GPS signals race, and the International Space Station cruises.

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Microscopic particles hurry about like rush hour drivers.

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Like any busy freeway,

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the upper atmosphere surges from all directions.

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The particles can create gridlock as they clump or flow.

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The varying traffic patterns can muddle GPS signals,

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disrupt spacecraft orbits,

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and even surge blackout-inducing currents through the Earth's crust.

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These effects pose risks to our infrastructure

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but our understanding of how gases and energy ebb and flow here remains hazy.

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For years, scientists have been running computer models

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to understand the upper atmosphere.

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But the models' capabilities depend highly on good observations

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-- and data from the region is scarce.

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To better navigate the upper atmosphere,

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NASA is counting on the Geospace Dynamics Constellation.

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Just as a news helicopter gives a bird's eye view of traffic in your area,

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GDC's fleet will fly through the upper atmosphere and report about current conditions.

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This specialized team of spacecraft will cover more than just local events.

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By varying their formation,

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the GDC fleet witll study phenomena at different scales,

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including regional and global perspectives.

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The increased coverage is similar to adding numerous weather tracking sensors,

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when previously there was only a handful covering just a few towns.

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The mission will be the first to measure the impacts of three distinct sources of energy

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that drive change in the upper atmosphere.

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Solar Radiation

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Terrestrial Weather

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And Charged Particles.

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The upper atmosphere changes in response to ultraviolet light

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and x-rays from the Sun.

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The amount of intense solar radiation can vary due to solar flares,

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the appearance of active regions on the Sun,

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and the 11 year solar cycle.

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Earth's weather effects expand and extend vertically,

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pounding the upper atmosphere with rippling force.

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Tropical storms, changes in the jet stream,

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and the El Niño/La Niña cycles all can be major drivers of the variability in this region.

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From outer space, electrical currents and charged particles

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stream into the upper atmosphere.

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These energy sources funnel down the Earth's magnetic field lines

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into the upper atmosphere.

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They heat, ionize, and stir the particles,

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surging in more traffic to the region.

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GDC will put us on route to understanding not only the high altitude conditions on Earth,

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but also provide an important database for exploring the atmospheres of other planets,

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in our Solar system,

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and beyond.

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Along the way from Earth to space, we have so much yet to learn.

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When it comes to navigating the upper atmosphere,

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GDC can show us the way.