What are the northern lights and what causes them?

Northern Lights, Finland

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The northern lights are a colorful undulating glow that can be seen in the night sky, usually in the north polar region. These lights are also called the "aurora borealis", which is Latin for "northern dawn". This phenomenon also occurs in the southern hemis phere. The lights near the south pole are called the "aurora austrailis".

What causes the northern lights anyway?

When electrically charged particles from the Sun collide with the Earth's upper atmosphere, they cause the atmospheric atoms and ions to radiate different colors and bands of light.

What do the aurora borealis look like?

If you look at the picture above, you see that the "aurora borealis" and "aurora austrailis" usually look like a diffuse glow of different colors or they can sometimes have a curtain-like appearance that extend out in an east-west direction. Sometimes, they form whispy arcs and other times they do a dance across the sky. The auroras are most likely shaped like the Earth's magnetic field.

The Earth's magnetic field

Our planet is like a gigantic magnet, because the Earth's magnetic field surrounds the entire planet and comes together in a funnel shape near the north and south poles. The Earth's magnetic field, called the magnetosphere, protects our planet from the Sun's radiation, this radiation is called the solar wind.

What is the source of the aurora?

The energy source of these dazzling lights in the night sky is the solar wind. The solar wind is a plasma sream of electrically charged particles that continuously flow out from the Sun.The particles from the solar wind get trapped and create the spectacle called the "aurora borealis".

Watch this Aurora Borealis video

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