Polar lights (aurora polaris) are a natural phenomenon found in both the northern and Southern Hemispheres. Northern lights are also called by their scientific name, aurora borealis, and southern lights are called aurora australis. The origin of the aurora begins on the surface of the sun when solar activity ejects a cloud of gas. Scientists call this a coronal mass ejection (CME). If one of these reaches earth, taking about 2 to 3 days, it collides with the Earth’s magnetic field. This field is invisible, and if you could see its shape, it would make Earth look like a comet with a long magnetic ‘tail’ stretching a million miles behind Earth in the opposite direction of the sun. When a coronal mass ejection collides with the magnetic field, it causes complex changes to happen to the magnetic tail region. These changes generate currents of charged particles, which then flow along lines of magnetic force into the Polar Regions. These particles are boosted in energy in Earth’s upper atmosphere, and when they collide with oxygen and nitrogen atoms, they produce dazzling auroral light. Aurora are beautiful, but the invisible flows of particles and magnetism that go on at the same time can damage our electrical power grid and satellites operating in space. This is why scientists are so keen to understand the physics of aurora and solar storms, so we can predict when our technologies may be affected. Can I see them anywhere? Aurora are more frequent at higher latitudes, closer to the poles (such as in Canada, Alaska, Antarctica), they have been seen closer to the equator as far south as Mexico. To view them, look in the direction of the closest pole (the northern horizon in the northern hemisphere, the southern horizon in the southern hemisphere). In some areas, such as Alaska or Greenland, they may be visible most nights of the year. And they occur at any time of the day, but we can’t see them with the naked eye unless it’s dark. Colors and patterns are from the types of ions or atoms being energized as they collide with the atmosphere and are affected by lines of magnetic force. Displays may take many forms, including rippling curtains, pulsating globs, traveling pulses, or steady glows. Altitude affects the colors. Blue violet/reds occur below 60 miles (100 km), with bright green strongest between 60-150 miles (100-240 km). Above 150 miles (240 km) ruby reds appear. Legends abound in northern cultures to explain the northern lights. Some North American Inuit call the aurora aqsarniit (“football players”) and say the spirits of the dead are playing football with the head of a walrus. Often legends warn children that the lights might come down and snatch them away. Some people claim to hear noises associated with the northern lights, but documenting this phenomenon has been difficult. The ends of the land and sea are bounded by an immense abyss, over which a narrow and dangerous pathway leads to the heavenly regions. The sky is a great dome of hard material arched over the Earth. There is a hole in it through which the spirits pass to the true heavens. Only the spirits of those who have died a voluntary or violent death, and the Raven, have been over this pathway. The spirits who live there light torches to guide the feet of new arrivals. This is the light of the aurora. They can be seen there feasting and playing football with a walrus skull. The whistling crackling noise which sometimes accompanies the aurora is the voices of these spirits trying to communicate with the people of the Earth. They should always be answered in a whispering voice. Youths dance to the aurora. The heavenly spirits are called selamiut, sky-dwellers, those who live in the sky. The east Greenland Eskimos thought that the northern lights were the spirits of children who died at birth. The dancing of the children round and round caused the continually moving streamers and draperies of the aurora. The Mandan of North Dakota explained the northern lights as fires over which the great medicine men and warriors of northern nations simmered their dead enemies in enormous pots. The Menominee Indians of Wisconsin regarded the lights as torches used by great, friendly giants in the north, to spear fish at night. An Algonquin myth tells of when Nanahbozho, creator of the Earth, had finished his task of the creation, he traveled to the north, where he remained. He built large fires, of which the northern lights are the reflections, to remind his people that he still thinks of them. So Interesting!!! - Anna ✌️
Posted on: Fri, 05 Sep 2014 08:31:12 +0000
Trending Topics
Recently Viewed Topics
© 2015