To find the cause of the Northern Lights, first we must look at the sun. The sun acts as a power plant with its core being a staggering 14 million degrees with a pressure so large that hydrogen atoms are packed so tightly that they become helium. This nuclear reaction causes a release in energy. The light from the sun starts at the core and moves outward. In the outer layers the heat moves towards the surface in convection cells. The electrical currents of charged gas are what create magnetic fields inside the sun. On some parts of the sun, the magnetic fields push their way to the surface and the particles cool, thus causing dark spots on the sun. The electrically charged particles are called plasma. The electric field lines move outward into space and as this happens they break and a few billion tons of plasma is hurled into space. This is known as a solar storm. The storm can reach speeds of eight million kilometers per hour or 4,970,000 miles per hour. This means that it would take about 18 hours for the solar storm to reach Earth.

When the solar storm reaches Earth, the Earth’s magnetic field deflects the solar storms and the field lines join together. This acts as a “funnel” for the gas particles to pour down on the daylight side of the pole. This is known as the daylight aurora. Once the magnetic field lines that came from the sun bend towards the night side of the pole, the lines couple together. This eventually leads to the field lines breaking like a “rubber band.” The gas from the solar storm then goes along the Earth’s magnetic field lines and goes towards the poles on the night side of the Earth, thus causing the night time aurora.

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