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    An aurora is a natural light display that shimmers in the sky Colorful blue, red, yellow, and lights shift gently and change shape like softly blowing curtains. Auroras are only visible at night, and usually only appear in lower polar regions. 
    Auroras are visible almost every night near the Arctic and Antarctic Circles, which are about about 66.5 degrees north and south of the Equator. In the north, the display is called Aurora Borealis, or northern lights. In the south, it is called Aurora Australia, or southern lights. 
    The activity that creates auroras begins on the sun. The sun is a ball of superhot gases made up electrically charged particles called ions. The ions, which continuously stream from the sun's surface, called the solar wind. As solar wind approaches the Earth, it meets the Earth's magnetic field. In ionosphere, the ions of the solar wind collide with atoms of oxygen and nitrogen from the Earth's atmosphere. The energy released during these collisions causes a colorful glowing halo around the poles - an aurora.
    Most auroras happen about 97-1,000 kilometers (60-620 miles) above the Earth's surface. The most active auroras happen when the solar wind is the strongest. The solar wind is usually fairly constant, solar weather-the heating and cooling of different parts of the sun-can change daily. Some increased activity in the solar wind happens during every equinox.

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