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Every second,

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one million tons of matter is blasted from the Sun

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at the velocity of one million miles per hour,

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and it's on a collision course

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with Earth!

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But don't worry,

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this isn't the opening of a new Michael Bay movie.

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This is The Journey of the Polar Lights.

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The Northern and Southern Lights,

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also known as the Aurora Borealis

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and Aurora Australis, respectively,

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occur when high energy particles from the Sun

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collide with neutral atoms in our atmosphere.

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The energy emitted from this crash

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produces a spectacle of light

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that mankind has marveled at for centuries.

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But the particles journey isn't just as simple

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as leaving the Sun and arriving at Earth.

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Like any cross-country road trip,

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there's a big detour

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and nobody asks for directions.

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Let's track this intergalactic voyage

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by focusing on three main points of their journey:

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leaving the sun,

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making a pit stop in the Earth's magnetic fields,

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and arriving at the atmosphere above our heads.

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The protons and electrons creating the Northern Lights

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depart from the Sun's corona.

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The corona is the outermost layer

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of the Sun's atmosphere

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and is one of the hottest regions.

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Its intense heat causes the Sun's hydrogen

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and helium atoms to vibrate

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and shake off protons and electrons

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as if they were stripping off layers on a hot, sunny day.

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Impatient and finally behind the wheel,

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these free protons and electrons move too fast

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to be contained by the sun's gravity

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and group together as plasma,

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an electrically charged gas.

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They travel away from the sun

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as a constant gale of plasma,

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known as the solar wind.

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However, the Earth prevents the solar wind

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from travelling straight into the planet

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by setting up a detour,

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the magnetosphere.

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The magnetosphere is formed

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by the Earth's magnetic currents

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and shields our planet from the solar winds

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by sending out the particles around the Earth.

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Their opportunity to continue the journey

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down to the atmosphere

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comes when the magnetosphere is overwhelmed

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by a new wave of travellers.

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This event is coronal mass ejection,

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and it occurs when the Sun shoots out

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a massive ball of plasma into the solar wind.

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When one of these coronal mass ejections

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collides with Earth,

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it overpowers the magnetosphere

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and creates a magnetic storm.

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The heavy storm stresses the magnetosphere

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until it suddenly snaps back,

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like and overstretched elastic band,

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flinging some of the detoured particles towards Earth.

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The retracting band of the magnetic field

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drags them down to the aurora ovals,

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which are the locations

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of the Northern and Southern Lights.

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After travelling 93 million miles across the galaxy,

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the Sun's particles finally produce

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their dazzling light show with the help of some friends.

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Twenty to two hundred miles above the surface,

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the electrons and protons meet up

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with oxygen and nitrogen atoms,

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and they sure are happy to see each other.

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The Sun's particles high five the atoms,

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giving their energy

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to the Earth's neutral oxygen and nitrogen atoms.

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When the atoms in the atmosphere

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are contacted by the particles,

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they get excited and emit photons.

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Photons are small bursts of energy

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in the form of light.

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The colors that appear in the sky

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depend on the wavelength of the atom's photon.

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Excited oxygen atoms are responsible

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for the green and red colors,

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where as excited nitrogen atoms produce

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blue and deep red hues.

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The collection of these interactions

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is what creates the Northern and Southern Lights.

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The polar lights are best seen on clear nights

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in regions close to magnetic north and south poles.

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Nighttime is ideal

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because the Aurora is much dimmer than sunlight

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and cannot be seen in daytime.

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Remember to look up to the sky

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and read up on the Sun's energy patterns,

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specifically sunspots and solar flares,

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as these will be good guides

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for predicting the auroras.