What Causes the Auroral Lights?
![](/spaceweather/images/aurora_particle_animated.gif)
This animation demonstrates very simply how different elements at different heights, let off energy that we see as different colors. You'll notice in the static aurora picture, it almost seems as if there are layers of colors one on top of the other.
Movie adapted from original clips provided courtesy of Professor Patricia Reiff, Rice University Connections Program
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The aurora is formed when particles from the Sun enter the Earth's atmosphere. This causes the atmosphere to light up. We see these lights and call them aurora. Different elements cause different colors in the sky.
- Nitrogen glows blue and red.
- Oxygen glows green and red.
Since blue, green and red light sometimes happen together, it mixes to give a lot of different colors (such as purple and pink).
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Visit the
Space Weather section to learn more about the aurora
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