Saturday, November 16, 2019
Dynamic Universe 1 Journal Essay Example for Free
Dynamic Universe 1 Journal Essay From the very beginning, the studying for the universe has been accompanied with numerous misconceptions and myths: from flat structure of the earth and earth-centered model of the universe to contemporary astrology and horoscopes. From the critical perspective, if the early explanations about the universe and our place in it could be explained due to known technological limitations of the ancients, modern astrology does not have any viable explanations. As Phil Plait argues on his website Badastronomy. com, modern astrology cannot be considered a science a priori and there are many reasons to make us support this statement. Unlike astronomy, which is based on universally developed methodologies, derived primarily from physics, chemistry, and mathematics, astronomy does not use any of them. The latter lacks even universally agreed method, as Phil Plait explains, some astrologists claim that ââ¬Å"the moment of birth is important, others say its the month, etcâ⬠¦ but they all operate under a very broad working assumption: there is some sort of force from the heavens that influences us here on Earth. â⬠Although during the development of the astronomy there have been various differences in theories and ideas, for instance Big Bang model, all of them were developed on the thorough scientific analysis of data and mathematical models coupled with specific methodologies. With some deviations, astrology can be compared to Sun worship practices during the ancient times. Naturally, Sun worship originated in agricultural areas due to the peopleââ¬â¢s heavy dependence of the sun light for the crop. If assessed critically, Sun worship has been a dominated religious practice. Wikipedia online encyclopedia indicates that Sun worship has been characteristic for Egyptian, Japanese and Nordic mythologies. Ancient Greeks also worshiped Helios, God of the Sun. Simultaneously, the list of solar deities provides even more evidence about the dominance of Sun worship during the early periods of ancient civilizations. Surprisingly, Smithbrad traces important connections of Sun worship and astronomical basis to the Christian religion, indicating both historical and scriptural evidence. For observers from the earth, the Sun and the Moon represent two most bright objects on the sky. However, from the critical perspective, these objects are not unique, not only by their form but also by the characteristics of their light. Practically, the story of star formation is a study in contradictions. It starts with atoms, molecules, and dust particles floating aimlessly in the dark and frigid depths of interstellar space. Out of the cold and empty expanses, gravity brings these scattered particles together to form stars. Over hundreds of millions of years, these gas and dust particles congregate into enormous clouds that can span hundreds of light-years. The two lightest elements hydrogen and helium dominate these clouds, accounting for about 92 percent and eight percent of the atoms, respectively (NASA, 2005). Dust grains account for about one percent of a clouds total mass. Astronomers call these clouds giant molecular clouds because they also contain trace amounts of molecules such as water, alcohol, ammonia, and various carbon-based organic compounds, which represent raw components of life. All in all, the clouds contain enough material to form tens of thousands of new stars. Magnetic fields and the random motions of gas molecules prevent the cloud from collapsing under its own weight. The various gas and dust particles jostle about, but eventually, enough mass congregates in one region to initiate gravitational collapse in a small portion of the cloud. Astronomers once thought that cloud collapse was usually triggered by external disturbances, such as supernova shock waves or stellar winds. Nowadays, however, most astronomers think that cloud collapse usually happens on its own, although triggering mechanisms can still play an important role (NASA,2005). Over the course of several millennia, a collapsing gas cloud fragments into tens to thousands of relatively dense, rotating clumps of gas that will ultimately form newborn stars. Emission and reflection nebulae are abundant in the universe, though not observed with the naked eye. Practically, emission nebulae, ââ¬Å"cloud of gas and dust floating in space,â⬠emit their own light, due to the presence of ultraviolet radiation coming from the hot star or star clusters stars (Nebulae, 2005). The very hot star emits highly energetic radiation of the invisible part of the electro-magnetic spectrum, and the emission nebula re-emits the radiation in the visible light (M42, 2005). Unlike the reflection nebulae, in the emission nebulae the atoms of the dust are energized by the radiation (ultraviolet) and start emitting (not reflecting) their own radiation as atoms fall back into lower energy states. This process of the radiation emission can be compared to the Sun, with the only deviation that the latter emits radiation and light due to the processes which occur in the Sunââ¬â¢s core without any impact from the outside object. Simultaneously, reflection nebulae reflect the light coming from the star or star cluster. This process can be compared to the Moon, as it also reflects the light coming from the Sun, not emitting its own radiation. From its own origin when being formulated by Lemaà ¾tre and proved by Hubble, the Big Bang theory evidenced many contributions, objections and simplifications. The Hubble Law states that galaxies in every direction are distancing away from us with speeds proportional to their distance. The major contribution to the Big Bang theory has been made with the data obtained from satellites COBE and WMAP, and the Hubble Space Telescope. The data allowed scientists to formulate the statement that the universe has been formed 14 billion years ago in a hot, dense, event known as the ââ¬Å"Big Bang. â⬠Practically, what the theory of ââ¬Å"Big Bangâ⬠provides is the explanation of nature and major characteristics of the universe. There is no edge or boundaries in the universe. The expansion of the universe is occurring at all points simultaneously. Therefore, as Richard Powell explains the most of 350 billion galaxies which contains the universe are moving away from one another. However, it does not necessarily mean that the Earth or our galaxy is moving. As it is known, galaxies are distributed not universally. The systems similar to our Solar System and the Milky Way are formed from under the gravity and thus are restrained from moving apart. However, 350 billion galaxies and 3. 5 trillion dwarf galaxies in the universe are collected into vast sheets, clusters and superclusters of galaxies surrounding large voids. Bibliography Phil Plait. Astrology, available at http://www. badastronomy. com/bad/misc/astrology. html Accessed Oct 3, 2005 The resource is dedicated to various misconceptions in the astronomy, including numerous myths and beliefs, like astrology, pseudoscience and science portrayal in contemporary movie industry. Wikipedia Encyclopedia. ââ¬Å"Solar Deityâ⬠available http://en. wikipedia. org/wiki/Solar_deity Accessed Oct 3, 2005 World Largest Open Encyclopedia, which offers explanations on various issues, including the astronomy and related subjects. Though not cited, this resource http://en. wikipedia. org/wiki/Big_Bang#Hubble. 27s_law_expansion became very useful for the journal preparation. Smithbrad ââ¬Å"Sun Worshipâ⬠Available http://smithbrad. nventure. com/sunworship. htm Accessed Oct 3, 2005 Resource aims to provide connections between Christian faith and practices with the Sun worship tradition as the most ancient tradition among all religions. The resource provides both scientific and scriptural evidence for its statements. ââ¬Å"Nebulaeâ⬠Available http://www. seasky. org/cosmic/sky7a05. html Accessed Oct 3, 2005 Web resource is dedicated primarily for concise and practical explanations of astronomical terms and phenomena. It offers graphic and photo illustrations to explains various issues in the astronomical science. NASA. ââ¬Å"Imagine the Universeâ⬠Available http://imagine. gsfc. nasa. gov This resource provides information for star life cycle patterns, which was useful for conducting the journal, particularly on the questions on emission and reflection nebulae. ââ¬Å"M42â⬠Available http://www. seds. org/messier/m/m042. html Accessed Oct 3, 2005 The resource is a part of the Messier Catalog. It became useful for the journal discussion on reflection and emission nebulae, offering photo illustrations and discovery history of Orion Nebula, also known as M42 Richard Powell ââ¬Å"Atlas of the Universeâ⬠Available http://anzwers. org/free/universe Accessed Oct 3, 2005 It is the most useful resource for general explanation of the Big Bang theory, providing graphical illustrations of its major concepts and problematic moments. Maps compiled by Mr. Powell has been used for journal explanations and references.
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