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liftoff of the mighty delta iv heavy

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rocket in august 2018 in cape canaveral

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florida nasa launched parker solar probe

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to touch the sun after spending a few

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years spiraling closer to our star the

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spacecraft has finally arrived

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it is amazing

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pakistan folk is touching the sun and

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this is nora

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the project scientist of the mission he

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has been waiting for this moment since

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the beginning of his career

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this is a dream come true one of the

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major goals for the pakistan mission is

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to fly through the solar corona and we

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are doing that now

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so what does it mean to touch the sun to

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answer that we need to look at the sun

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structure

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unlike earth the sun doesn't have a

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solid surface it's a giant ball of hot

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plasma that's held together by its own

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gravity

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solar material flows out from the

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surface

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but around the sun it's bound by the

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sun's gravity and magnetic field this

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material forms the sun's atmosphere the

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corona eventually some of this hot and

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fast solar material escapes the pull of

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the sun and gushes out into space as

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solar wind

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the boundary that marks the edge of the

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sun's atmosphere is known as the alphane

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critical surface we didn't know exactly

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where this boundary was

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but for the first time in history a

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spacecraft has crossed it parker solar

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probe ventured into the corona touching

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solar material still bound to the sun

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the wispy corona is too faint to see

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most of the time but it's revealed

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during total solar eclipses

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for centuries we've been studying the

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sun's atmosphere during eclipses because

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it's important for understanding how our

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star influences life in the solar system

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but much about the corona remains a

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mystery two of the most challenging

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scientific mysteries in astrophysics

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occur in a region that we call solar

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corona

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the first mystery is about the

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temperature the corona is about 300

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times hotter than the photosphere the

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visible surface of the sun below

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secondly there's a constant stream of

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particles flowing from the sun known as

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the solar wind it accelerates up to

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millions of miles per hour out of the

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corona and we don't know how

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solarwind can disrupt our satellites and

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technology to better protect them we

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need to go where the solar wind starts

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in the corona so heading there has been

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a key goal of nasa's for a while

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we first proposed the idea of sending a

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spacecraft to the sun in 1958 we didn't

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have the technology to withstand the

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journey until the 2000s

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since its launch in 2018 parker has been

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heading towards our star

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then in april 2021 during parker's

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eighth orbit around the sun the

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spacecraft was around 20 solar radii or

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8 million miles from the sun's surface

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when it crossed into the corona

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this is a huge milestone it took us over

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six decades to come to this point

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as parker entered the corona its whisper

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instrument took these images streams of

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plasma surrounded the spacecraft and

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parker's other instruments detected that

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the magnetic conditions had changed

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outside the corona solar wind gushes out

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pushing solar material away at high

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speeds so that it can't return back to

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the sun's surface

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inside the corona the sun's magnetic

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field becomes much stronger

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solar material is slower and tethered to

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the sun

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instead of a smooth divide parker found

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that the boundary between these two

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sides is wrinkly

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these bumpy ridges are created from huge

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flows of plasma traveling out of the

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corona

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scientists are not sure why this happens

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but as parker gets closer we're finding

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more clues

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before entering the corona parker had

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seen kinks in the solar wind where it

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would momentarily double back on itself

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scientists called these features in the

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solar wind switchbacks but no one knew

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how or where they formed

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in 2021 the spacecraft finally tracked

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switchbacks to one of their origins

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as parker got even closer to the sun it

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detected bursts of switchbacks

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scientists trace these bursts all the

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way to the visible surface of the sun

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here we see distinct cells

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as heat rises beneath these convection

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cells churn and create funnels of

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magnetic energy above the surface

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scientists found that switchbacks form

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inside these funnels before rising into

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the corona and beyond

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this is only one piece of the

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switchbacks puzzle though

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exactly how they form is still unknown

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over the next few years parker will keep

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looking for clues as it explores our sun

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the only star we can study up close

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the sun is also the only star known to

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support life

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so understanding it is critical as we

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search for life beyond our solar system

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that will link directly into the

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question are we alone in this universe