aurora

noun
au·ro·ra | \ə-ˈrȯr-ə, ȯ-\
plural auroras or aurorae\-(ˌ)ē \

Definition of aurora 

(Entry 1 of 2)

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

Aurora

geographical name
Au·ro·ra | \ə-ˈrȯr-ə, ȯ-\

Definition of Aurora (Entry 2 of 2)

1 city in north central Colorado east of Denver population 325,078

2 city west of Chicago in northeastern Illinois population 197,899

3 town north of Toronto in southeastern Ontario, Canada population 53,203

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Other Words from aurora

Noun

auroral \-əl \ adjective
aurorean \-ē-ən \ adjective

Examples of aurora in a Sentence

Noun

a gorgeous pink aurora aroused us out of our slumber

Recent Examples on the Web: Noun

Falcke says the team will study solar flares, the aurora of Jupiter, and the galaxy's radio emissions. Daniel Clery, Science | AAAS, "China’s moon mission will probe cosmic dark ages," 16 May 2018 To get an idea of what’s in store, these bright bands of green auroras were captured just after midnight on Tuesday over Lake Superior near Copper Harbor, Michigan. Lyndsey Matthews, Country Living, "There's Another Chance to See the Northern Lights Tonight," 11 Apr. 2018 This stream of particles can mingle with Earth’s magnetic field, causing geomagnetic storms that mess with our satellites and power grid and create auroras. Loren Grush, The Verge, "The NASA spacecraft that will journey to the Sun just got its super deluxe heat shield," 8 July 2018 Elders tell their stories and a narrator tells us of the sun's essential role in creating the aurora. Ned Rozell, Anchorage Daily News, "Where myth meets science: The northern lights in Nuiqsut, seen inside a portable planetarium," 21 Apr. 2018 An aurora’s colors depend on what kind of atom cosmic particles smash into. Robert Ormerod, National Geographic, "Why Space Fans Flock to This Eerie Landscape," 9 Apr. 2018 Bright, colorful aurora, visible to the naked eye, lit up the night sky in both hemispheres. Angela Fritz, Washington Post, "A solar shock wave cracked Earth’s magnetic field last night, but everything is fine," 20 Apr. 2018 As well as studying the aurora and magnetosphere, Juno also helps scientists probe the gravitational field of Jupiter’s interior in exquisite detail by monitoring small tweaks to the spacecraft’s orbit—down to 1,900 miles below the clouds. Andrew Coates, Newsweek, "NASA Juno Unlocks Secrets of Jupiter's Mega Cyclone Clusters," 8 Mar. 2018 National Geographic reports that aurora chasers and citizen scientist photographers began to spot a purple plasma ribbon in the night sky a few years ago. Gabriella Paiella, The Cut, "Rare and Majestic Natural Phenomenon Named … Steve," 16 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'aurora.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of aurora

Noun

14th century, in the meaning defined at sense 1

History and Etymology for aurora

Noun

Latin — more at east

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Statistics for aurora

Last Updated

28 Aug 2018

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Time Traveler for aurora

The first known use of aurora was in the 14th century

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Thesaurus: All synonyms and antonyms for aurora

Spanish Central: Translation of aurora

Britannica.com: Encyclopedia article about aurora

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