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the northern lights
the sun is stormy and has its own kind of weather. it is so hot and active that even the suns gravity cannot hold its atmosphere in check! energy flows away from the sun toward the earth in a stream of electrified particles that move at speeds around a million miles per hour. these particles are called plasma, and the stream of plasma coming from the sun is called the solar wind. the more active the sun, the stronger the solar wind.
the solar wind constantly streams toward the earth, but dont worry because a protective magnetic field surrounds our planet.the same magnetic field that makes your compass point north also steer the particles from the sun to the north and south poles. the charged particles become trapped in magnetic belts around the earth. when a large blast of solar wind crashes into the earths magnetic field, the magnetic field first gets squeezed and then the magnetic field lines break and reconnect.
the breaking and reconnecting of the magnetic field lines can cause atomic particles called electrons trapped in the belts to fall into the earths atmosphere at the poles. as the electrons fall to the earth, they collide with gas moleculesin the atmosphere, creating flashes of light in the sky. each atmospheric gas glows a different color. oxygen and nitrogen glows red and green and nitrogen glows violet-purple. as these various colors glow and dance in the night sky, they create the northern lights and the southern lights.
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