WEBVTT FILE

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The Sun.

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It’s the solar system’s engine,

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and the only star in the sky that gets our attention…

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every day.

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But up close,

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it’s unlike anything we can see from Earth.

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It’s ferocious—

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a writhing mass of nuclear chaos,

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tangled magnetic lines,

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and a constant wind with inconceivably high temperatures

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and speeds close to a million miles an hour.

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Over the years NASA has sent probes all over the solar system…

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...but never to the Sun.

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Check this out.

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This is the Parker Solar Probe…

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…and it’s going to be humanity’s first mission assigned to touch the Sun.

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It will fly to within 4 million miles of the Sun’s surface

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confronting brutal radiation

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and temperatures that can reach 1,000,000 degrees Fahrenheit.

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Parker Solar Probe has been prepped

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to fly right through that unforgiving atmosphere.

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It's a rough journey.

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Typically, if you want to head out into the solar system,

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you merge with orbital traffic.

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But if you want to head toward the center of the solar system,

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you've got to run the other way…

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and it takes a lot of energy.

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once it arrives, the spacecraft has got to take the heat.

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Bathed in radiation as it swoops in close,

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Parker Solar Probe will use an advanced

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carbon/carbon composite heat shield

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o protect its delicate instruments.

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And here’s a technical triumph:

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the spacecraft’s thermal regulation system

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will use just a single gallon of ordinary water

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H 2 O

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to collect and then dissipate heat…just like a car radiator.

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It will fly into the corona,

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the super hot region of gas and plasma surrounding the Sun.

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There’s hardly a there there,

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as high energy particles fly outward like streamers.

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But – and this is another weird thing about the sun-

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-the corona is hotter than the surface of the star itself.

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We have a few good theories about this–

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but we're really not sure why.

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There's some process in the atmosphere that keeps heating it up

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even as it gets further away from the core.

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Parker Solar Probe is going to try and figure it out.

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The corona also propels the solar wind out into space

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at incredible speeds

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way beyond the orbit of Pluto.

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No one knows for sure what accelerates it so far so fast.

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Parker Solar Probe is going to fly right through the origin of this wind,

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right where it starts, to figure out how the whole system works

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We can’t see those processes from Earth, or even from space.

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Parker Solar Probe is our first direct encounter with a star.

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Our Sun is the only star we can visit….

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…which means this mission will gather

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important information about how stars work…everywhere.

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That’s information we can only get by going straight to the source.

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Some journeys are harder than others.

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Some destinations are further, higher, hotter.

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But the only way to explore a new destination

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is to actually make the journey.

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Parker Solar Probe:

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See you on The Sun.