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Affichage des articles dont le libellé est Astronomy picture of the day - 2018 December 19 - A Rainbow Geminid Meteor. Afficher tous les articles
Affichage des articles dont le libellé est Astronomy picture of the day - 2018 December 19 - A Rainbow Geminid Meteor. Afficher tous les articles

19/12/2018

A Rainbow Geminid Meteor - Astronomy picture of the day - 2018 December 19

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A Rainbow Geminid Meteor 
Image Credit & Copyright: Dean Rowe

Explanation: Meteors can be colorful. While the human eye usually cannot discern many colors, cameras often can. Pictured is a Geminid captured by camera during last week's meteor shower that was not only impressively bright, but colorful. The radiant grit cast off by asteroid 3200 Phaethon blazed a path across Earth's atmosphere longer than 60 times the angular diameter of the Moon. Colors in meteors usually originate from ionized elements released as themeteor disintegrates, with blue-green typically originating from magnesiumcalcium radiating violet, and nickel glowing green. Red, however, typically originates from energized nitrogen and oxygen in the Earth's atmosphere. This brightmeteoric fireball was gone in a flash -- less than a second -- but it left a wind-blown ionization trail that remained visible for several minutes, the start of which can be seen here.

Gallery: Geminid Meteors 2018 

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