Aurora Borealis (Northern Lights)

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Norway and Svalbard, Sweden, Finland, Russia, USA, Canada and Iceland.

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The northern lights are an atmospheric phenomenon that's regarded as the Holy Grail of skywatching.

The northern lights, or the aurora borealis, are beautiful dancing waves of light that have captivated people for millennia. But for all its beauty, this spectacular light show is a rather violent event.

Energized particles from the sun slam into Earth's upper atmosphere at speeds of up to 45 million mph (72 million kph), but our planet's magnetic field protects us from the onslaught. 

As Earth's magnetic field redirects the particles toward the poles — there are southern lights, too, which you can read about below — the dramatic process transforms into a cinematic atmospheric phenomenon that dazzles and fascinates scientists and skywatchers alike.

Though it was Italian astronomer Galileo Galileiwho coined the name "aurora borealis" in 1619 — after the Roman goddess of dawn, Aurora, and the Greek god of the north wind, Boreas — the earliest suspected record of the northern lights is in a 30,000-year-old cave painting in France.

Since that time, civilizations around the world have marveled at the celestial phenomenon, ascribing all sorts of origin myths to the dancing lights. One North American Inuit legend suggests that the northern lights are spirits playing ball with a walrus head, while the Vikings thought the phenomenon was light reflecting off the armor of the Valkyrie, the supernatural maidens who brought warriors into the afterlife.

Early astronomers also mentioned the northern lights in their records. A royal astronomer under Babylon's King Nebuchadnezzar II inscribed his report of the phenomenon on a tablet dated to 567 B.C., for example, while a Chinese report from 193 B.C. also notes the aurora, according to NASA.

The science behind the northern lights wasn't theorized until the turn of the 20th century. Norwegian scientist Kristian Birkeland proposed that electrons emitted from sunspots produced the atmospheric lights after being guided toward the poles by Earth's magnetic field. The theory would eventually prove correct, but not until long after Birkeland's 1917 death.