Aurora Borealis Jacob Campbell Reannen Brewer
History: Aurora Borealis • French astronomer Pierre Gassendi is credited for naming the Aurora. • As Far back as 700 A.D. people have told about the “Northern Lights”, mostly the Eskimos and Scandinavian people. • Around 1200 A.D. the Norse Literature referred to the lights as the Northern Dawn. Aurora Borealis has been the scientific term for the Northern Dawn since 1620.
Interpretations of the Aurora Borealis: Good Interpretations Bad Interpretations Eskimos: Believed that if they did not go inside the lights would take their heads and use them to play games. Rinnmarks-Vidda- It was taught that if they mocked the lights they would oscilate rapidly and take their life. Icelanders: Believed that if pregnant woman gazed at the lights, their children would be born cross eyed • Norse: They believed the aurora was the Bifrost, which is a heavenly bridge between Earth and Asgard. • Finland: Believed that the Archangel Michael lite up the skies to battle the devil Beelzebub. • Lapps: The Lapps people were convinced the lights were from the battle between Thor and the Mountain Kind. • Danish: Believed the swans had flown too far north and had their wings frozen, every time they flapped the Northern lights would reflect off their wings. • Watch video.
Can You Hear the Aurora? No Yes In 2012 a study in Finland recorded a sound about 230 feet in the air that they believed to be coming from the Aurora. Some people (it is a rare occurrence) Have said they can hear the Aurora and it sounds like the crackling of a radio. Listen to sound According to physicist BezLaderman you cannot hear the aurora because it is too high. “the aurora is 50 miles above us, in the upper atmosphere. Which means it has to travel through 75 times the amount (as a airplane) to reach us. The atmosphere is thinner as well.” Low frequency radial receiever constructed at the university of Iowa the electrons striking the atmoshphere generate intense radial immisions over a frequency range of about 100-500 kHz.
How Magnets Create the Aurora • In early twentieth century America, a common story was that the Aurora was caused by the sun reflecting off of the icebergs in the North Pole. Though the Aurora is created in part by the sun, it is not a reflection. The suns powerful solar storms disturb the Earth’s magnetic field. This field then rearranges itself then converts a part of its stored energy into fast moving particles. These particles, partly from earth and partly from the sun flow towards earth, they encounter the ionosphere where there energy is increased. The particles collide with Nitrogen and Oxygen atoms, producing the aurorallight. There is no direct contact of the solar particles in the Polar Regions to create the aurora, Solar flares have no effect on the Aurora Borialis.
Why is the Aurora different colors The colors of the Aurora are caused when particles from the Sun collide with atoms in the Earth’s atmosphere. Depending on which type of atom it (the particles) collide with determine the color. Since oxygen is the most common in the Earth’s atmosphere that’s where most of the particles collide. Oxygen in the lower latitude between 100 and 300 km can create the most common color of green and yellow and very rarely do collisions above 300 km in the upper atmosphere with oxygen result in a rare red Aurora. Colors Oxygen- Green and Yellow Ionized nitrogen- blue Excited Nitrogen- Red Commonly Aurora’s are Red at the top, Green in the middle and a combination of blue and green at the bottom. If our atmosphere had high concentration of neon gas the Auroral would be orange.
Other planets with Auroras: • Jupiter • Io, Europa, and Ganymede Moons. • Saturn • Uranus • Neptune • Mars