aurora


au·ro·ra

noun \ə-ˈrr-ə, -\
plural auroras or au·ro·rae\-(ˌ)ē\

Definition of AURORA

1
:  dawn
2
capitalized :  the Roman goddess of dawn — compare eos
3
:  a luminous phenomenon that consists of streamers or arches of light appearing in the upper atmosphere of a planet's magnetic polar regions and is caused by the emission of light from atoms excited by electrons accelerated along the planet's magnetic field lines
au·ro·ral \-əl\ adjective
au·ro·re·an \-ē-ən\ adjective

Examples of AURORA

  1. <a gorgeous pink aurora aroused us out of our slumber>

Origin of AURORA

Latin — more at east
First Known Use: 14th century

Other Astronomy Terms

gibbous, nadir, nebulous, penumbra, retrograde, sidereal, syzygy, wane, wax, zenith

Au·ro·ra

geographical name \ə-ˈrr-ə, -\

Definition of AURORA

1
city N cen Colorado E of Denver pop 325,078
2
city NE Illinois pop 197,899
3
town Canada in SE Ontario pop 53,203

aurora

noun    (Concise Encyclopedia)

Luminous phenomenon of the upper atmosphere that occurs primarily at high latitudes. Auroras in the Northern Hemisphere are called aurora borealis, or northern lights; in the Southern Hemisphere they are called aurora australis, or southern lights. Auroras are caused by the interaction of energetic particles (electrons and protons) from outside the atmosphere with atoms of the upper atmosphere. Such interaction occurs in zones surrounding the Earth's magnetic poles. During periods of intense solar activity, auroras occasionally extend to the middle latitudes.

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