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Explanation cosmic rays in 1912 the austrian

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Explanation: Cosmic Rays. In 1912, the Austrian physicist Victor Hess carried an electroscope up in a balloon. He found that the conductivity of the air increased with altitude. Apparently, the radiation that ionized the air came either from high in the atmosphere or from beyond the Earth. In 1928, this idea was further researched when electroscopes were sealed and put into a lake. They found that the greater the depth, the lower the radiation levels. Cosmic rays are affected only slightly by the _______ except during violent solar flares, which increase the energy received in the form of cosmic rays. Explanation: Sun. At one time it was believed that the sun was the primary source of cosmic rays, but it has since been proven that the effect of the sun is minimal except during solar flare episodes. The majority of cosmic rays approach the Earth in equal amounts from all directions, not primarily from the sun. Most astronomers are of the hypothesis that cosmic rays originate within the ____________. Explanation: Galaxy. An extragalactic origin for cosmic rays seems unlikely as these particles would spread themselves very thinly over the vast distances of intergalactic space. Therefore, an origin within the galaxy is the assumed hypothesis. Many astronomers feel that the most promising candidates for the origin of cosmic rays are _________________. : Supernovae. Supernovae are rare, but particles ejected from them and accelerated to high energies in galactic magnetic fields could be stored in the galaxy for many millions of years. If electrons are ejected in supernovae explosions, atomic nuclei are probably poured into interstellar space as well. Possibly the primary cosmic ray particles that now bombard the Earth are tiny fragments of stars that exploded millions of years ago. A cloud of interstellar gas or dust is called a ____________. Explanation: Nebula. Nebulae is the plural word and is the Latin word for clouds. One of the earliest catalogues of nebulous-appearing objects was prepared in 1781 by the French astronomer ___________ ____________. : Charles Messier.
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Messier was a comet hunter and he placed on record 103 objects that might be mistaken for comets. Because Messier's list contains some of the most conspicuous star clusters, nebulae, and galaxies in the sky, these objects are often referred to by their number in his catalogue. For example, M31, the great galaxy Andromeda: By 1908, nearly 15,000 ___________ had been catalogued and described, with some being identified as star clusters and others as gaseous nebulae. Explanation: Nebulae. The efforts of William and John Herschel, Charles Messier, and J.L.E. Dreyer made this catalogue possible. A New General Catalogue was developed and most bright galaxies were given new numbers. M31, the Andromeda Galaxy, is known in the New General Catalogue as NGC224. A ____________ variable is a star that belongs to one of two classes of yellow supergiant pulsating stars.
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