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Ever since we’ve been pointing spacecraft at the Sun,

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two regions on our star have been missing from satellite images.

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The Sun’s two poles, have never been mapped

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 because all the solar imagers we have built, have remained in the ecliptic plane 

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— the swath of space roughly aligned with the Sun’s equator where all the planets orbit.

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A new mission from the European Space Agency and NASA called Solar Orbiter

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 aims to escape this plane and take the very first images of the poles.

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The planets are all moving and circling the Sun,

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so we already have some velocity going one way.

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 If we want to launch up, out of the ecliptic, it requires more energy.

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To get outside the ecliptic plane, Solar Orbiter uses Earth’s and Venus’ gravity

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to slingshot itself into a view of the poles.

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The only other satellite to fly over the poles was Ulysses,

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which launched in 1990 to study the solar atmosphere. 

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But Solar Orbiter will be the first mission to capture actual images of this hard-to-reach region.

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Scientists think the poles could be the missing piece

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to understanding what drives the Sun’s activity. 

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Every 11 years, the Sun's magnetic field flips

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— north becomes south, and vice versa.

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This mysterious process has direct effects on Earth. 

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Before the poles flip, solar activity reaches its peak. 

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The number of eruptions increases,

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sending powerful bursts of solar material that can potentially harm our astronauts and satellites. 

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We don’t really have a good understanding of the global solar behavior.

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Another one of the mission’s goals

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is to monitor how these eruptions and solar material travel through space. 

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Using a suite of 10 instruments, 

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Solar Orbiter observes an active region on the surface as it explodes

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and then it also takes measurements as the escaping material passes directly by the spacecraft. 

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Solar Orbiter will give us a comprehensive full view of the entire Sun 

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and how the Sun is impacting throughout the entire solar system.

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At closest approach, Solar Orbiter will be closer to the Sun than Mercury 

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at a mere 26 million miles away

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— the ideal distance to get a comprehensive view of the Sun and its surrounding atmosphere.  

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It will fly close to the Sun every six months

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and endure temperatures more than 900 degrees Fahrenheit. 

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To survive the intense radiation, a large titanium shield protects the instruments, 

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while a carefully orchestrated dance of opening and closing eye holes in the shield

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allows the instruments to peep out at the right time.

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Other instruments will directly measure solar material from behind the shadow of the shield. 

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All these observations will tell us more about the Sun than we’ve ever known before 

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and by the end of the 7-year mission, we will have seen our star in a completely new way. 

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Our undestanding of the Sun will change dramatically.

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I will say that we are living in a revolutionary moment in our field.

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