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 B. 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 striking the Earth's magnetic field.
The theory would eventually prove correct, but not until long after Birkeland's death. At any given moment, the sun is ejecting charged particles from its corona, or upper atmosphere , creating what's called the solar wind. When that wind slams into Earth's ionosphere , or upper atmosphere, the aurora is born.
In the Northern Hemisphere, the phenomenon is called the northern lights aurora borealis , while in the Southern Hemisphere, it's called the southern lights aurora australis. The bright colors of the northern lights are dictated by the chemical composition of Earth's atmosphere.
While solar wind is constant, the sun's emissions go through a roughly year cycle of activity. Then, the particles let out all that energy in the form of light instead of bubbles.
Our eyes see green best out of all the colours, so we see green the brightest when we look at the northern lights. It is easiest to see the northern lights in winter when is it very dark at night, and also outside of cities and away from street lights. You are more likely to see them the further north you are too. Check out this great website Aurora Watch from Lancaster University — it might just help you find them!
Hello, curious kids! Ask an adult to send your question — along with your name, age and town or city where you live — to curiouskids theconversation. Send as many questions as you want! More Curious Kids articles, written by academic experts:. Bright, consistent auroras are most visible during the height of sunspot activity. Some increased activity in the solar wind happens during every equinox. These regular fluctuations are known as magnetic storm s.
Magnetic storms can lead to auroras being seen in the midlatitude s during the time around the spring and autumnal equinox es. Auroras have been visible as far south as the Yucatan Peninsula in Mexico. Magnetic storms and active auroras can sometimes interfere with communications. They can disrupt radio and radar signals. Intense magnetic storms can even disable communication satellite s. Coloring an Aurora The colors of the aurora vary, depending on altitude and the kind of atoms involved.
If ions strike oxygen atoms high in the atmosphere, the interaction produces a red glow. This is an unusual aurora—the most familiar display, a green-yellow hue, occurs as ions strike oxygen at lower altitudes. Reddish and bluish light that often appears in the lower fringes of auroras is produced by ions striking atoms of nitrogen. Ions striking hydrogen and helium atoms can produce blue and purple auroras, although our eyes can rarely detect this part of the electromagnetic spectrum.
To find out more about the mysterious light displays, scientists have launched satellites specially designed to study auroras. Fox Fire In Finland, the aurora borealis is called revontulet , which literally translates to fox fires.
According to one Finnish folk tale, the lights are caused by a magical fox sweeping his tail across the snow and sending sparks up into the sky. Dawn Wind The aurora borealis , or northern lights, was studied by ancient Roman and Greek astronomers.
The phenomenon was named for the Roman goddess of the dawn, Aurora, and the Greek god of the north wind, Boreas. Also called the southern lights. Also called the northern lights. Gas molecules are in constant, random motion. Also called a temperate zone. These particles originate from our star - the sun. The sun is constantly pushing out a stream of electrically charged particles called the solar wind, and this travels out from the sun at between and km per second in all directions. As the Earth travels around the sun, a small fraction of particles from the solar wind are intercepted by the planet.
When these charged particles hit the atoms and molecules high up in our atmosphere, they become excited. This creates two glowing rings of auroral emission around the North and South magnetic poles, known as auroral ovals. As they decay back to their original state, they emit distinctive colours of light. The realisation of the enormity of the universe washes over you, and you feel small in a good way and full of wonder.
These atoms become excited at different levels in the atmosphere. The most common colour seen in the Northern Lights is green.
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