In order to glean information about stars, astronomers analyze electromagnetic emissions, or the light, that reaches Earth. A spectroscope is basically a device that focuses a beam of light through a prism, which divides the light into characteristic colors that can then be seen using an eyepiece or screen. The resulting spectrum is used to determine the chemical composition of stars. The lines on the spectrum, or spectral lines, are associated with known elements. In 1868, an unknown element was discovered and given the name helium. It was almost thirty years before the element would be detected on Earth (McMillan, 2011).
The accepted classification scheme is a combination of two, the Harvard system types stars based on surface temperature and the MK system, which types stars based on luminosity. In the 1880s, the Henry Draper catalogue of stars was being compiled at the Harvard College Observatory. During this time, more types of stars were discovered and labeled using letters of the alphabet based on hydrogen spectral line strength. Eventually, the types were listed in non-alphabetical order based on surface temperature, resulting in the O, B, A, F, G, K, M classification system. This order of stellar types ranges from O, bluish-white stars with surface temperatures from twenty-five thousand degrees Kelvin to fifty thousand degrees Kelvin, to M, red stars with surface temperatures of approximately three thousand degrees Kelvin. The Sun is a type G star (Stellar Classification, 2014).
Stars are born, evolve, and after millions or billions of years they die. Stars are formed in vast interstellar molecular clouds when gravity overpowers heat, which leads to disequilibrium in the cloud and causes contract...
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...ook (The Almagest) in 150 AD that summarized Greek astronomical knowledge. It catalogued one thousand twenty-two stars, with estimates of their brightness, arranged in the forty-eight original constellations. Ancient Greeks named stars according to their position in a constellation, for example a star in the Taurus the Bull constellation was known as “the reddish one on the southern eye”, this star’s Arabic is name is Aldebaran. In the tenth century, Al-Sufi, one of the greatest Arabic astronomers, published his version of The Almagest where he introduced the names of individual stars. Bedouin Arabs thought single stars represented people and animals, so they named them. While some of the star names in Al-Sufi’s book were translations of Ptolemy’s descriptions, many of the original meanings of the star names had long been forgotten (Constellations: FAQs, n.d.).
...f gas, which collapsed and broke up into individual stars. The stars are packed together most tightly in the center, or nucleus. Scientists believe it is possible that at the very center there was too much matter to form an ordinary star, or that the stars which did form were so close to each other that they coalesced to form a black hole. It is argued that really massive black holes, equivalent to a hundred million stars like the Sun, could exist at the center of some galaxies
Brown dwarfs are objects in space that sit between the lines of being a star and a planet. This object is dim and hard to distinguish from low mass stars at the early stages of the dwarf’s life. They are often called failed stars because they start their life the same way as regular stars. However, in some stage, they just didn’t have enough mass gathered to generate the fusion-powered energy of a star. Scientists are certain that brown dwarfs are the missing link between stars and planets but the formations of dwarfs are still a mystery.
& MCMILLAN, S. 2008. Astronomy Today - Sixth Edition, United States of America, Pearson Education, Inc.
It’s a white giant and has a temperature of 7700 Kelvin. It’s a type A star that is 8.5 times brighter than the sun. It is most likely to be in the last stage of ordinary star-type life. Scientists are saying the sun’s older twin is found in the middle of Capricorn. Studying this star will help them see how the Earth’s sun will develop.
Stars are born and reborn from an explosion of a previous star. The particles and helium are brought together the same way the last star was born. Throughout the life of a star, it manages to avoid collapsing. The gravitational pull from the core of the star has to equal the gravitational pull of the gasses, which form a type of orbit. When this equality is broken, the star can go into several different stages. Some stars that are at least thirty times larger than our sun can form black holes and other kinds of stars.
The Orion Nebula is a spectacular sight. Consequently, it has been a preferred target of the Hubble Space Telescope (HST) over recent years. The HST has provided a great deal of insight into the complicated process of star formation. In June of 1994, C.
Solar nebula is a rotating flattened disk of gas and dust in which the outer part of the disk became planets while the center bulge part became the sun. Its inner part is hot, which is heated by a young sun and due to the impact of the gas falling on the disk during its collapse. However, the outer part is cold and far below the freezing point of water. In the solar nebula, the process of condensation occurs after enough cooling of solar nebula and results in the formation into a disk. Condensation is a process of cooling the gas and its molecules stick together to form liquid or solid particles. Therefore, condensation is the change from gas to liquid. In this process, the gas must cool below a critical temperature. Accretion is the process in which the tiny condensed particles from the nebula begin to stick together to form bigger pieces. Solar nebular theory explains the formation of the solar system. In the solar nebula, tiny grains stuck together and created bigger grains that grew into clumps, possibly held together by electrical forces similar to those that make lint stick to your clothes. Subsequent collisions, if not too violent, allowed these smaller particles to grow into objects ranging in size from millimeters to kilometers. These larger objects are called planetesimals. As planetesimals moved within the disk and collide with one another, planets formed. Because astronomers have no direct way to observe how the Solar System formed, they rely heavily on computer simulations to study that remote time. Computer simulations try to solve Newton’s laws of motion for the complex mix of dust and gas that we believe made up the solar nebula. Merging of the planetesimals increased their mass and thus their gravitational attraction. That, in turn, helped them grow even more massive by drawing planetesimals into clumps or rings around the sun. The process of planets building undergoes consumption of most of the planetesimals. Some survived planetesimals form small moons, asteroids, and comets. The leftover Rocky planetesimals that remained between Jupiter and Mars were stirred by Jupiter’s gravitational force. Therefore, these Rocky planetesimals are unable to assemble into a planet. These planetesimals are known as asteroids. Formation of solar system is explained by solar nebular theory. A rotating flat disk with center bulge is the solar nebula. The outer part of the disk becomes planets and the center bulge becomes the sun.
Have you ever heard the phrase “We are stardust”? Chances are you have, but what exactly does that mean? As an Astronomy major and someone whose always been fascinated by the wonders of space, including the wonder of supernovas. I want to pass some of the information I have learned to you today by telling you the different types of supernova and what happens during a supernova.
However Spectroscopy is not a recent development, as it has been utilized for many years since Isaac Newton made the first advances in 1666. Spectroscopy is the study of light as a function of wavelength that has been emitted, reflected or scattered from a solid, liquid, or gas. Fundamentals of Spectroscopy Spectroscopy is the distribution of electromagnetic energy as a function of wavelength. Spectrum is basically white light dispersed by a prism to produce a rainbow of colours; the rainbow is the spectrum of sunlight refracted through raindrops. All objects with temperatures above absolute zero emit electromagnetic radiation by virtue of their warmth alone; this radiation is emitted at increasingly shorter wavelengths as temperature is increased.
If the nebula is dense enough, certain regions of it will begin to gravitationally collapse after being disturbed. As it collapses the particles begin to move more rapidly, which on a molecular level is actually heat, and photons are emitted that drive off the remaining dust and gas. Once the cloud has collapsed enough to cause the core temperature to reach ten-million degrees Celsius, nuclear fusion starts in its core and this ball of gas and dust is now a star. It begins its life as a main sequence star and little does it know its entire life has already been predetermined.
Supernovas are extremely powerful explosions of radiation. A supernova can give off as much energy as a Sun can within its whole life. A star will release most of its material when it undergoes this type of explosion. The explosion of a supernova can also help in creating new stars.
Where did astronomy originate? According to the Department of Astronomy, the earliest people to keep astronomical records where the Akkadians (they lived in what is later known as the northern part of Babylon). The earliest date is from around 2,500 B.C. The ancient Akkadian priests were the first to record these astronomical records. They recorded these records because it helped them predict some of the Sun’s motions, and the Earth’s moons, and the stars. These records included observations of the daily, monthly, and yearly positions of the stars and planets. These records explained the geographical locations of the planets. The records also helped with them being able to judge when to plant and harvest crops and with religious ceremonies.
Astronomy dates back to ancient times when peoples such as the Babylonians, Egyptians, and Chinese kept written records of astronomical events and occurrences. Today’s seven day week originates from the Babylonians’ seven important bodies in the night sky: the Sun, Moon, Mars, Mercury, Jupiter, Venus, and Saturn. The ancient Egyptians used the stars to align their pyramids and many of their corridors in almost perfect north-south or east-west directions. The Chinese were experts at predicting solar eclipses. They believed that a solar eclipse was a dangerous warning. Chinese astronomers were executed if they failed to predict an eclipse.
The education system in India is based on forced learning that kills student’s spirit and zest of learning. In the film “Like Stars on Earth,” we look specifically at the draw backed role played by parents and teacher in Indian education system. We follow the story of a dyslexic Indian boy, Ishaan, who always had trouble coping with his studies, but in the end with the help of an understanding teacher he is able to study normally and catch up with his peers. We will analyze this film using the concepts from Practices of Looking to explain our thesis. Eddie will cover the concepts of encoding and the ideology surrounding Indian education; Kiranjot Singh will explain the concepts of punctum, negotiated reading and producer’s intended meaning;