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Our heliosphere,

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this giant bubble

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around the Sun and planets,

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is like our “house” in space

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because it keeps out

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the weather

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coming from the galaxy

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beyond.

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We know this because we can

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see what happened

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when it leaked.

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Beyond the walls of our

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cosmic “house,”

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you’ll find one of the most

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dangerous forces in space:

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Galactic cosmic rays are

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near-light speed particles

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that shoot out from

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supernovas

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and other distant explosions,

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and they pelt our heliosphere

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from all directions.

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But our heliosphere

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pushes back.

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The Sun’s solar wind

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and magnetic fields

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act like insulation

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around our “house,”

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deflecting most of these

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dangerous particles away.

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Still, some get through,

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and we can actually

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see the scars

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they leave in trees.

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When cosmic rays

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collide with Earth’s

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atmosphere,

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they create rare particles

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that are eventually

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metabolized by trees.

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By studying tree rings,

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we can identify times

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when more cosmic rays

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rays reached Earth —

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like during a 70-year period

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in the 1600s

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when solar activity

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was unusually low

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and the heliosphere

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was weaker.

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NASA’s IMAP mission

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will help us understand

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how our weather-proofing

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system works,

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and how it’s affected

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by changes in our Sun.

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How studying our heliosphere

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can aid in the search

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for life elsewhere.