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Earth is like our

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bedroom,

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cozy and safe.

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But it’s inside a

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much bigger house

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that helps make our

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planet habitable.

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That house is our heliosphere,

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a giant, protective

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bubble created by the Sun.

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It stretches beyond the planets

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and forms a boundary

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that protects our solar system

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from deep space.

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So, what does this

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“house” look like?

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Well, we don’t actually know!

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The heliosphere is so huge

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that we can’t

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just step outside

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and take a photo

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of the whole thing.

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But NASA has found ways

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to map out its boundaries.

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First, two spacecraft

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have actually passed

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through its walls

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and sent back measurements

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from outside.

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Voyager 1

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passed through in 2012.

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And Voyager 2 made its own

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crossing six years later.

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But they only found

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the boundary

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in two specific places,

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and it took more than 35

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years of space travel

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to get there!

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Luckily, there are other ways

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to study

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the heliosphere from inside.

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NASA’s IMAP

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will use a technique

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kind of like listening

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for “echoes” that bounce off

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our heliosphere’s

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exterior walls.

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Instead of sound waves,

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these “echoes” are particles

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that ricochet

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off of the heliosphere’s

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edges.

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By “listening” carefully,

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scientists can map

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the structure

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of our “house” from

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the inside,

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giving us a “blueprint” of our

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solar system’s outer shell.

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Next time:

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How our

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heliosphere protects us

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from the dangers

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of deep space,

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and what happens

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when it fails.