Auroras
In certain polar regions of the earth, a rare and fascinating phenomenon occurs in the dark season of winter. This phenomenon is called the Northern Lights, or auroras. In areas where auroras can be seen, the sun shines brightly for six months and then disappears for the next six. The sun follows a straight path across the sky, rising in the north and setting in the south. This is because of the latitude of these regions. Unlike other regions of earth, the polar regions either completely face the sun or don’t face it at all. During the first six months of the long, endless nights of dark winter, auroras are frequently seen, almost every night, in fact. During the rest of the year, the summer months, when the sun is up even in the middle of the night, auroras can only be viewed by using complicated scientific telescopes. These auroras are produced by a series of solar reactions, they have given scientists much to study, and ordinary people the basis of many myths and legends.Long ago, in an effort to explain auroras, people made up their own myths and legends to explain them. Auroras were a power which they feared and respected. Some thought that there was a direct connection between natural disasters like droughts a
However, modern science has shown that the scientific cause behind an aurora is very complicated and affected by certain climate conditions. The process starts in the sun, where high energy particles are blown away and escape the sun’s magnetic field and surface in a “high vacuum electrical discharge”. These particles accelerate at high speed in “an ever widening spiral” called the garden hose effect, because it resembles water coming out of a garden hose that rotates above a person’s head. In about three days, the particles reach earth, but they are stopped by the earth’s magnetic field and encase the earth in “ a comet-shaped cavity called the magnetosphere”. The comet shape is compressed on the daylight side and drawn out into a tail-like shape on the night time side. Since the open magnetic field lines are weak only in polar regions, the particles accelerate towards them. The high energy particles collide with air molecules, which causes their speed energy to change to light energy. During the collision they are discharged and then either ionized or neutralized, depending on whether a particle is neutralized or ionized, determines the color of an aurora. nd volcanic eruptions and the occurrence of an aurora. Others thought they were
Some common words found in the essay are:
Northern Lights, , Aurora Borealis, energy particles, polar regions, magnetic field, northern lights, particles collide, energy particles collide, caused oxygen atoms, garden hose, atoms altitude, occur magnetosphere, oxygen atoms altitude, color aurora, natural disasters,
Approximate Word count = 877
Approximate Pages = 4 (250 words per page double spaced)
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