George Stimpson

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What causes the northern lights?

The northern lights have never been explained satisfactorily. Scientists have been studying them for generations but have not yet been able to determine the exact cause of these fireworks of nature, and theories explaining them are subject to continual revision. The ancients watched the northern lights with awe and ascribed to them a supernatural origin. In Roman mythology Aurora was the goddess of the dawn and Boreas was the personification of the north wind. Aurora signifies "dawn" and borealis "north," hence the northern lights are called aurora borealis. When it was learned that a similar us phenomenon occurs in the south polar region the southern lights were called aurora australis, "south dawn." Aurora polaris is the generic name for both the northern and the southern lights. These spectacular phenomena, among the most beautiful and marvelous in feature, are believed to be produced somehow by vast electrical discharges in the earth's upper atmosphere originating with or induced by the sun. The general theory is that something from the sun breaks up the molecules of the atmospheric gas, electrifies them, causes them to be drawn toward the poles of the earth and renders them susceptible to the earth's magnetic field. In other words, electrons from the sun ionize the rarefied gases at low pressure in the upper atmosphere and it takes place on a grand scale is similar to what takes place in miniature in a neon-sign light. Miniature synthetic auroras can be produced in laboratories. Molecules of air in a glass tube are bombarded with a current of electricity and made to glow in waves of color similar to the northern and southern lights. The northern lights range from a bright glow to active streamers. Sometimes they cover the whole sky with a quivering mass of feathery flames. The long, slender beams of light of various colors form an arc in the heavens. ten there are coronas, rays, arcs, crisscrosses and other discharges of red, green, yellow and blue lights that brighten the skies. There seems to be some relationship between the aurora polaris and sunpots, but just what it is has not been determined definitely. Very bright displays of the northern lights are frequently accompanied by magnetic disturbances that disrupt telegraph, cable and radio communications. [page 60] Aurora polaris is rare within forty-five degrees of the equator and is more frequent farther north although it is not common within six degrees of the poles. The northern lights are most frequent in October and April and most rare in December and June. They have been o served in the United States as far south as Georgia and New Mexico It is not uncommon for displays of the northern lights to be mistaken for the glow of a distant fire. The height of the northern lights is said to range from ten miles to more than a hundred above the earth. Because of their undulatory motion they are sometimes called the "Merry Dancers" in England. The French call them chèvres dansantes, "dancing goats." "Lord Derwentwater's lights" is a local name of the northern lights in the north of England, because there was an unusually vivid and weird display of them on the night in 1716 that James, Earl of Derwentwater, was beheaded for rebelling against his sovereign.