What Causes the Northern Lights

September through March, anywhere in Iceland—sitting in a hot spring, standing on a volcano, searching for puffins along the ocean rocks—the sky suddenly dances with light, and you wonder if you’re still on Earth or whether you took off to a magical world of imagination.

It’s not a dream. It is real. Most call it the Northern Lights. The scientific term is Aurora Borealis. Icelanders call it Norðurljós (Dawn of the North), a name that dates back to 13th century Norse. A Viking in ancient times (and even modern times) will tell you the lights are the Valkyries brandishing their swords from the backs of galloping warhorses decked out with shimmering helmets, spears and armor. (The Valkyries determine who lives and who dies in battle, and who among the slain may travel on to Valhalla, Viking heaven.)

Science explains the Northern lights differently, and to understand the explanation we must review some basic astronomy.

The Sun is surrounded by a magnetic field which extends into space. The field is made of particles (protons and electrons) which boil off and shoot through the cosmos with incredible velocity. This “shooting off” is called the solar wind.

The Earth, too, is surrounded by a magnetic field, also composed of protons and electrons. The solar wind from the sun presses on this field in much the way our breath will compress a soap bubble. This compressed area is called the magnetosphere. This collision of the Sun’s solar wind with the Earth’s magnetosphere causes the Aurora Borealis (Northern Lights).

The pressure of the solar wind creates electrical voltage—around 10,000 volts. This voltage accelerates the protons of the Earth’s magnetic field toward the north and south poles. This push against the poles begins to build up in the ionosphere (the upper regions of the Earth’s atmosphere) at the poles, shoving highly accelerated electrons against atoms of gas. This collision causes the gas atoms to release energy, which makes the gas atoms glow—and makes them dance across the sky.

The colors of the Northern Lights depend upon which particular gas is being energized the most, and the altitude where the most activity occurs. The colors most often associated with the Aurora Borealis are pink, green, yellow, blue, violet, and occasionally orange and white.

At altitudes of 241 km (150 miles), green light typically zips across the aether, particularly with oxygen atoms. Red occurs at the same altitude, when the released energy involves nitrogen atoms. On the other hand, nitrogen atoms will appear purple or violet, and sometimes blue at only 96.5 km (60 miles) above the Earth.

The Northern Lights trip the light fantastic above Iceland in static patterns, and often as moving patterns that sweep the sky, stretching usually around 80 km (50 miles) from beginning to end, and appear as either bands, arcs, or spirals.

Winter is the best time to see Northern Lights in Iceland. The sky is dark as much as nineteen hours of the day, and the Earth is tilted at an angle with the sun for maximum interaction.

The best part is, when visiting Iceland, you don't have to do anything. With over nine locations throughout the country, Berjaya Hotels it situated everywhere you need to be to see the Northern Lights.  Not far from Reykjavik, we recommend the following locations to view the Northern Lights:  Berjaya Hotel Fludir, Berjaya Hotel Hamar, and Berjaya Hotel Vik.  Cheers!

You might also be interested in:

The Best Time to See Iceland’s Northern Lights

http://www.icelandairhotels.com/en/blog/icelands-northern-lights

Iceland’s Midnight Sun

http://www.icelandairhotels.com/en/blog/icelands-midnight-sun

The Midnight Sun in Iceland

http://www.icelandairhotels.com/en/blog/the-midnight-sun-in-iceland

Things to do in Iceland in Winter

http://www.icelandairhotels.com/en/blog/iceland-winter-activities