Black Holes Essays (837 words) - Black Holes, Astrophysics, Galaxies

Black Holes On December 3, 1995, astronomers using the Hubble Space Telescope identified a black hole in the galaxy NGC 4621, located 100 million light-years from Earth in the direction of the constellation Virgo. This is the second super-massive black hole that astronomers using the Hubble Space Telescope have found. Astronomers believe that the mass of this black hole is about 1.2 billion times the mass of our sun, but it is concentrated in a space that is not any bigger than our solar system There are two puzzling questions that astronomers are trying to answer. The black hole is fueled by the galaxy and its 800 light-year-wide spiral disk of dust. Before the discovery of this black hole, astronomers did not think that there was any dust in elliptical galaxies like NGC 4261. Currently they believe that the disk of dust is the remnant of a smaller galaxy that fell into the core of NGC 4261. The black hole will swallow up the gas from the smaller galaxy over the next 100 million years. Researchers believe that while the gas is being swallowed by the black hole, the process will produce some amazing fireworks. The second puzzling question that astronomers are trying to answer is why isn't the black hole at the center of the galaxy? According to images from the Hubble Space Telescope, the black hole is 20 light-years from the center of the galaxy, but since the black hole is so massive it is hard to explain how it could have been moved. One idea is that the black hole is moving itself. Some astronomers think that the disk of dust serves as a "fuel tank." The black hole sucks in the material which is absorbed by gravity, compressed, and heated to tens of millions of degrees. This theory would explain why radio telescopes have observed radio jets, or hot gas exhausts from the black hole's area. The exhaust may be pushing the black hole across space, as a jet engine gives thrust to a plane. According to Ted Bunn, an astronomer at Berkley University, "A black hole is a region of space that has so much mass concentrated in it that there is no way for a nearby object to escape its gravitational pull, not even light." So, what does that mean? The following example will explain the nature of a black hole. A ball is thrown up into the air. It rises for a while, but it eventually falls. If the ball is thrown fast enough it is able to escape the gravitational field and continue rising. This is called the "escape velocity." The escape velocity depends on the mass of the planet, which affects the gravitational field. A object on Earth would have to travel at 25,000 m.p.h. to escape the gravitational pull of Earth. Now imagine an object with a gravitational pull so large and escape velocity so high that even visible light could not escape it. This is a black hole. How are black holes formed? To our best knowledge, black holes are created at the end of a very large star's life cycle. The star collapses into a white dwarf, which is the smallest, dimmest, and hottest of all stars. Matter is packing continually tighter and tighter together and gravity is increasing. The white dwarf will collapse into itself when it runs out of fuel, thus creating a black hole. Therefore only very massive stars can form black holes because only large stars have enough mass and gravitational pull to collapse into itself. What are the parts of a black hole? There are two main parts to a black hole. The first one is the event horizon and the second is the singularity. The event horizon is the spherical surface that marks the boundary of the black hole. You can pass into the black hole through the horizon, but you cannot pass back out of it. Once you have crossed the horizon, you are doomed to "hit" singularity. The singularity is the center of the black hole and all that astronomers know about it is that the gravitational pull is so large that anything reaching it would be torn to pieces. Astronomers are continuing to

Essay on The Progressive Decay of Freedom

Essay on The Progressive Decay of Freedom Essay on The Progressive Decay of Freedom The Progressive Decay of Freedom The universal healthcare portrayed by supportive media and politicians appears attractive and helpful, but the fine print might reveal a not-so-nice picture. In order to combat the rising cost in healthcare and limited availability to those in need, the United States government is formulating a plan for universal healthcare. Although this type of healthcare is used in many other countries, the effects of a universal plan for Americans will be harmful. Universal healthcare will not benefit America as a whole because it will raise taxes, it will limit the availability of certain treatments, and it will infringe on the personal rights and freedoms of Americans. Universal healthcare will not benefit America because it will raise taxes. The estimated national cost of universal healthcare over the next ten years is 1.1 trillion dollars and has only been increasing (â€Å"Cost of Obamacare†). In order to offset the cost, the federal government has already increased income taxes for wealthier families and businesses that make over a certain amount of money annually (â€Å"Cost of Obamacare†). This increase in taxes affects all physicians, because they will be treating patients and paying for patients’ health insurance through higher taxation. Not only are physicians affected financially from the increased taxes, but there is now less incentive for many people to pursue a career as a physician. Many supporters of universal healthcare will argue that universal healthcare works for other countries and has been proven successful. By taking a closer look at these countries and their economies, we can see that many have rarely had any other option of healthcare made available. The lack of experience these countries have with other healthcare options directly inhibits the ability to compare and contrast the success of the healthcare systems currently used in those countries. The countries with universal healthcare also have higher income taxes than other countries. France, for example, has a max income tax of 75%, depending on tax the bracket, leaving citizens a mere 25% of what they earn (â€Å"List of Countries by Tax Rates†). A very common misconception of this Affordable Care Act is that it will provide every uninsured American with free health insurance. It will not provide free health insurance to all who cannot afford it because the decision to expand Medicaid is left up to the state. Georgia is one of over twenty states that has decided to not to opt into the Medicaid expansion. Without the expansion of Medicaid, many uninsured and less fortunate citizens will remain without insurance and face an annual penalty. In fact, the non-exempt citizens remaining uninsured by January 2014 will face a yearly tax penalty that increases every year the citizens remain uninsured (â€Å"Health Insurance Basics†). With an economy that is attempting to climb out of a recession and millions without coverage, the reality of higher taxes is paired with the delusion of having readily available care. Universal healthcare will not benefit Americans because it will limit the availability of certain treatments. Access to affordable health insurance for many uninsured people is appealing, but improved access to insurance does not mean improved access to care. It is projected that the new demand for healthcare will strain healthcare facilities and personnel. The rapid increase of patients will decrease the availability of common procedures such as, pap smears and cardiac catheterizations. There will also be longer waiting periods for specialized treatments such as, organ transplants and spinal procedures. I personally know a young man in Canada who suffered the loss of his leg because of the lack of availability of appropriate care. Joe Messerli, in an article on universal healthcare, states, â€Å"Stories constantly come out of universal health care programs in Britain and Canada about patients forced to wait months or years for treatments that

Week 7 Essay Example | Topics and Well Written Essays - 500 words - 4

Week 7 - Essay Example Thus, artists through their works concentrated on individualism themes and reason in order to reform the society from reliance on traditional and faith-based ideologies. The anamorphic image in Hans Holbein’s The Ambassadors is in the skull. It represents Jean de Dinteville and his friend who acted as French ambassadors’ to England and the Republic of Venice respectively. The hierarchy of genres in order importance is history painting, portrait painting, genre painting, landscape painting, animal painting, and still life painting. History painting involved uplifting or inspirational messages on religious, historical, mythological, classical, or literary context. History painting marked the demonstration and conclusion of skills acquired within the academy system. Portrait painting is the second in the genre and is represented by large portraits of heroic figures for public viewing, and in some cases for private portraiture. This came after rigorous course by academy students to master the skill, which first started with drawing from plaster casts, copying the established portraits, and finally creating live models. Genre paintings involved scenes of ordinary life containing animals, landscapes, people, portraits, or touches of still life. The academy artists employed skills with occasional humor that put this genre in number three in the hierarchy. Landscape painting involved painting of art pieces whose focus was the portrayal of lovely sceneries of rivers, mountains, seascape, townscape, or countryside. This type of painting required less technical ability from the academy artists as compared to the first three genres. Animal painting in the fifth category dealt with painting of animals originating from the popularization of horse painting from 1724-1806. Finally, still life painting consisted of a representation of flowers, kitchen implements, fruits among other foodstuffs in a painting. Because