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Jet planes can travel faster than sound

Jet planes can travel faster than sound

The distance of about 150,000,000 kilometers, the sun is the earth’s most proximate star.   At over one hundred times the diameter of the earth, and at more than 360,000 times its mass, the sun’s enormity is hard to imagine. Providing the light and heat on earth, this huge star is the generator and maintainer of all life and all life processes on this planet. Newly noted are indications that a solar activity known as sunspots may have given rise to certain historical occurrences.

Appearing on the photosphere, the surface of the sun, and sometimes visible to the naked eyes, are sunspot’s, dark patches known to exist for at least 2,000 years, although first scientifically studied in the seventeenth century by Galileo. It was, in fact, from studying the movement of sunspots that Galileo was able to conclude that the sun was a sphere rotating on its axis. With his telescope he perceived that the sunspots, which moved daily in a westerly direction, seemed to move at a slower rate near the limb than near the center of the sun.

Examined through a telescope, the sunspots are seen to have a dark center or shadow, the umbra, surrounded by a lighter area, the penumbra. ‘ All this appears superimposed on the granulation of the photosphere. The granules, which make up the photosphere, are the main convection mechanism of surface energy transport from the interior, hotter areas of the sun. Most recent theorists have suggested that sunspots arise from a complex physical process determined by the uneven nature of solar rotation. Unlike the earth, which rotates at a constant rate all over the globe, the sun. a gaseous rather than a rigid body, docs not rotate uniformly. The equatorial regions rotate once every twenty-five days, while the polar regions take thirty-one days to complete one revolution. During this uneven rotation, magnetic lines of force get whipped up almost like cream being whipped in a bowl. Then centrifugal force, buoyancy, and turbulence further twist the lines of force and bring them to the surface, where they appear as sunspots.

Magnetic field intensities of up to 4,000 gauss have been recorded in the center of a sunspot. Often covering areas as large as :he earth itself, these powerful magnetic fields are in many cases :en times the size of the earth. The sunspots typically produce temperatures of about 8,500K, which is significantly cooler than the average photosphere temperature of 5,000 K. Very bright on their, sunspots only appear to be dark against the photosphere because they are 30 percent as bright as the sun’s surface.

Occurring mostly near the middle of the photosphere, sun-pots are predominantly a phenomenon of the middle and 3w latitudes. The number of sunspots intermittently varies somewhat. At different times there may be as many as a hundred f them all at once, or none at all. The life span of smaller sun-pots for the most part lasts less than a day, although larger ones away last a week or two and sometimes as long as a month.

Most interesting is the phenomenon of the 2-year average unstops cycle. It is not known what causes this periodicity, although recent theorists have proposed some convincing arguments placating Jupiter, with its 8-year solar rotation. It is suggest that this planet may be instrumental in inducing tidal action and unstops.Recorded also, however, are long periods of quiescence? the longest of which occurred over a seventy-five-year period.

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