Hipparcos Mira Variable Stars
ABSTRACT
From the visual and infrared light curves we are trying to find the phase changes and correlate them to Infrared shift and magutdes to see what is happing to Mira type stars as they age. Most of the radiation in the star is in the Infrared. The method being used O-C and fitting mean light curves. All mira variables pulsate undergoing rapid mass loss. In the conclusion we show that the magnitude has a positive correlation with the phase shift.
I.Introduction
Studies of Mira variables are of considerable importance in stellar astrophysics because they are pulsating stars undergoing rapid mass loss. During one cycle, which typically lasts from 200-500 days, these stars undergo significant changes in their observable properties. At some point in their lives, many if not most stars go through an unstable phase that leads to pulsation. They are evolving through the tip of the asymptotic giant branch (AGB) in the H-R diagram and are affected by two significant processes. In the interior, helium shell flashes cause large excursions in their luminosity’s and period on a timesscale of ten of thousands of years. In the outer layers, pulsation-enhanced mass loss, which reduces their envelope masses and drives their evolution to the white dwarf. The atmospheres of Mira variables are very deep and there effective diameters change markedly with wavelength because of the opacity effects. The massive
winds of Miras are believed to be driven by a combination of dust formation and shocks induced by stellar pulsation. (Willson). Understanding the nature of shocks and measuring their properties is essential to understanding the physics of pulsation and mass loss from pulsating stars.
This paper presents an analysis of visible and IR (JHKL) data for 2 Long Period Variables (LPV). The four pulsating variables chosen are classified as Miras. All Miras stars are Long period variables that exhibit a very large change in visible light because they are cool (less than or equal to 3000K), and so most of their radiation lies in the infrared. We are studying the Mira stars instead the irregular stars because to understand any star you must first start with the simplest model then expand upon that, Mira are relatively well-behaved long period variable.
II. Data Search
For this study we required stars that had already been studied intensively, so that both IR data and visual data were available for many cycles.
The eponymous building-The Yacoubian Building- is an art deco apartment block, and all Egyptians live - from the rich to the poor who live on its top floor. In the recent past, Egypt has been rogue by a series of demonstration and violation of human rights. Contemporary Egypt seems to have regress from its original state to the present torn down state. Egypt therefore, is marred by a myriad number of problems. The realism and the forthrightness of the film captures the frustrations and disappointments of the Egyptian people, illuminates the government injustices and corruption, as well as criticizes the Islamism program and false religious piety. The Yacoubian Building film, which is a metaphor for Egypt, gives us a little insight on what exactly happens—homosexuality, political Islam, terrorism, torture, social inequality, political corruption and religious hypocrisy.
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2, Alter Dinsmore, Cleminshaw H. Clarence, Philips G John. Pictorial Astronomy. United States: Sidney Feinberg, 1963.
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The FAA works on the gradual incorporation of rules and considerations in order to guarantee security and privacy. The U.S. Congress expects that in 2015 commercial drones will be ready to fly under regulated circumstances, but experts said that it would be until 2020 that unmanned aerial system are fully integrated. Nevertheless, laws will be published step by step according to their complexity and grade of autonomy. First small drones will be allowed to fly than larger ones, first drones operated by a ground-based pilot than automate long distance flights, and areas wi...
Dyson, Marianne J. Space and Astronomy: Decade by Decade. New York: Facts on File, 2007. 14+. Print.
Research News Planetary Scientists are Seeing the Unseeable Richard A. Kerr Science, New Series, Vol. 235, No. 2 -. 4784. The. Jan. 2, 1987, pp. 113-117. 29-31. The 'Standard' of the 'Standard'. Stable URL:
...actions of the occupants of the Yacoubian building provides the reader with many perceptions into Egyptian society. Perhaps, a reader may find these perceptions essential for the reason that they capture and offers some sort genuineness of Egyptian political and religious culture. “The Yacoubian Building” is a controversial novel that addressed and entertains anyone fascinated in contemporary Egypt subjects. It includes the honest interpretations of a variation of sexual repression, political corruption and abuse, and the dangers of religious extremism. Alaa al-Aswany goes to great length to clarify how the characters such as Busayna, Souad, Abduh and Taha are all victims of their corrupt society.
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Tyler, Pat. Supernova. NASA’s Heasarc: Education and Public Information. 26 Jan. 2003. 22 Nov. 2004
Initially, rubber has existed for an extensive period of time. When viewing the “early history of rubber development, [there] is evidence that rubber existed even before Columbus’ time” (Robert, E.A. 1952, p. 77). One of the earlier uses of rubber was documented in a Mexican Tribe where the natives of Mexico and West Indies played games using elastic balls (Robert, E.A. 1952, p. 77). Many scientists attempted to establish “suitable solvents for rubber since its arrival in Europe as a raw material in the late 1700s, however none had been successful” (Backer, C. 1997, p.14). Furthermore, it is relevant to say that the rubber industry was primarily established in Europe by Charles Macintosh, who was an industrial chemist in 1818 (Backer, C. 1997, p.14). Later on, the rubber industry began to devel...
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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;