|—n , pl -ras, -rae|
|1.||an atmospheric phenomenon consisting of bands, curtains, or streamers of light, usually green, red, or yellow, that move across the sky in polar regions. It is caused by collisions between air molecules and charged particles from the sun that are trapped in the earth's magnetic field|
|2.||poetic the dawn|
|[C14: from Latin: dawn; see |
|aurora (ə-rôr'ə) Pronunciation Key
Plural auroras or aurorae (ə-rôr'ē)
A brilliant display of bands or folds of variously colored light in the sky at night, especially in polar regions. Charged particles from the solar wind are channeled through the Earth's magnetic field into the polar regions. There the particles collide with atoms and molecules in the upper atmosphere, ionizing them and making them glow. Auroras are of greatest intensity and extent during periods of increased sunspot activity, when they often interfere with telecommunications on Earth. ◇ An aurora that occurs in southern latitudes is called an aurora australis (ô-strā'lĭs) or southern lights. When it occurs in northern latitudes it is called an aurora borealis (bôr'ē-āl'ĭs) or northern lights. See also magnetic storm.