The Early Type Stars

The Early Type Stars

Author: A.B. Underhill

Publisher: Springer Science & Business Media

Published: 2012-12-06

Total Pages: 295

ISBN-13: 9401035563

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At this time when astronomers are being surprised by the discovery of objects which emit a fabulously large amount of energy, that is the quasi-stellar radio sources and the quasi-stellar galaxies, and when by the means of space vehicles X rays, gamma rays and cosmic rays are being observed to come from the depths of interstellar space, one may ask why write a book about stars. Stars seem to be almost incidental when one looks at the universe in terms of exceedingly great energies. Nevertheless, stars exist. They are accessible to study and they have not yet revealed all their secrets. This is enough to arouse interest and to cause one to try to find answers to the questions which arise. The early type stars are particularly interesting because they are spendthrift stars pouring out their energy at a great rate. But their brilliance is also their undoing. They must evolve rather quickly, on an astrophysical scale. Thus by studying these stars we are studying a population in change. The implications from the local and from the cosmological viewpoint are important if one wishes to understand the details of stellar evolution and of galactic structure. Perhaps one of the simplest reasons for writing a book about the early type stars is to see if some of the conundrums pre sented by the spectra of these stars can be unravelled when all the available infor mation is brought together.


Stellar Spectral Classification

Stellar Spectral Classification

Author: Richard O. Gray

Publisher: Princeton University Press

Published: 2021-06-08

Total Pages: 611

ISBN-13: 1400833361

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Written by leading experts in the field, Stellar Spectral Classification is the only book to comprehensively discuss both the foundations and most up-to-date techniques of MK and other spectral classification systems. Definitive and encyclopedic, the book introduces the astrophysics of spectroscopy, reviews the entire field of stellar astronomy, and shows how the well-tested methods of spectral classification are a powerful discovery tool for graduate students and researchers working in astronomy and astrophysics. The book begins with a historical survey, followed by chapters discussing the entire range of stellar phenomena, from brown dwarfs to supernovae. The authors account for advances in the field, including the addition of the L and T dwarf classes; the revision of the carbon star, Wolf-Rayet, and white dwarf classification schemes; and the application of neural nets to spectral classification. Copious figures illustrate the morphology of stellar spectra, and the book incorporates recent discoveries from earth-based and satellite data. Many examples of spectra are given in the red, ultraviolet, and infrared regions, as well as in the traditional blue-violet optical region, all of which are useful for researchers identifying stellar and galactic spectra. This essential reference includes a glossary, handy appendixes and tables, an index, and a Web-based resource of spectra. In addition to the authors, the contributors are Adam J. Burgasser, Margaret M. Hanson, J. Davy Kirkpatrick, and Nolan R. Walborn.


The Analysis of Starlight

The Analysis of Starlight

Author: John B. Hearnshaw

Publisher: Cambridge University Press

Published: 2014-03-17

Total Pages: 385

ISBN-13: 1107031745

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A reference for astronomers and historians on astronomical spectroscopy, from the discovery of spectral lines through to the year 2000.


The Rotation of Sun and Stars

The Rotation of Sun and Stars

Author: Jean-Pierre Rozelot

Publisher: Springer Science & Business Media

Published: 2009-01-08

Total Pages: 266

ISBN-13: 3540878300

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The Sun and stars rotate in di?erent ways and at di?erent velocity rates. The knowledge of how they rotate is important in understanding the formation and evolution of stars and their structure. The closest star to our Earth, the Sun, is a good laboratory to study in detail the rotation of a G star and allows to test new ideas and develop new techniques to study stellar rotation. More or less massive, more or lessevolved objects, however, can have averydi?erent rotation rate, structure and history. In recent years our understanding of the rotation of the Sun has greatly improved. The Sun has a well-known large-scale rotation, which can be m- sured thanks to visible features across the solar disk, such as sunspots, or via spectroscopy. In addition, several studies cast light on di?erential rotation in the convective zone and on meridional circulation in the radiative zone of the Sun. Even the rotation of the core of the Sun can now be studied thanks to various methods, such as dynamics of the gravitational moments and of course, helioseismology, through g-modes analysis. Moreover, the magnetic ?eld is strongly linked to the matter motions in the solar plasma. The solar magnetic ?eld can be measured only at the surface or in theupperlayers.Itistheproductoftheinternaldynamoorofthelocaldynamos if they exist – in any case magnetic ?eld and rotation cannot thus be separated.


The Analysis of Starlight

The Analysis of Starlight

Author: J. B. Hearnshaw

Publisher: CUP Archive

Published: 1990-04-19

Total Pages: 554

ISBN-13: 9780521399166

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This book presents a detailed pedagogical account of the equation of state and its applications in several important and fast growing topics in theoretical physics, chemistry and engineering. This book is the storv of the analysis of starlight by astronomical spectroscopy. It describes the development of the subject from the time of Joseph Fraunhofer, who, in 1814, used a telescope-mounted prism to observe the spectral light emitted from several bright stars. He discovered that light was missing at certain colours (wavelengths) in the starlight, and these so-called spectral lines were subsequently shown to hold clues to the nature of the stars themselves. The book explains how the classification of stars using their line spectra developed into a major branch of astronomy whilst new methods in astrophysics made possible the approximate quantitative analysis of spectral lines in the 1920s and 1930s. After the Second World War these techniques were considerably improved when computers were programmed to model the structure of the outer layers of stars. Basic concepts in spectroscopy and spectral analysis are also covered and. finally. Dr Hearnshaw comments on the stellar spectroscopy of some individual star.


Observing Variable Stars

Observing Variable Stars

Author: Gerry A. Good

Publisher: Springer Science & Business Media

Published: 2012-12-06

Total Pages: 275

ISBN-13: 1447100557

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Observing variable stars is one of the major contributions amateur astronomers make to science. There are 36,000 variable stars listed in the General Catalogue of Variable Stars, so it is clearly impossible for the limited number of professional observatories to target even the majority of them. That's where amateur astronomers come in - thousands of them turning their telescopes to the sky every night. Variable star observing is the most popular of "real science" activities for amateurs, and Gerry Good's book provides everything needed. The first part of the book provides a highly detailed account of the various classes of variable star, with examples, illustrations and physical descriptions. The second section covers practical aspects of observing, everything from preparation and planning, through observing techniques, to data management and reduction.