Astronomer

About: Astronomer is a research topic. Over the lifetime, 1057 publications have been published within this topic receiving 7773 citations.

Astronomical Algorithms

Abstract: From the Book: When, in 1978, I wrote the first (Belgian) edition of my astronomical Formulae for Calculators, the industry of microcomputers was just starting its worldwide expansion. Because these "personal computers" were not yet within reach of everybody, the aforesaid book was written mainly for the users of pocket calculating machines and therefore calculation methods requiring a large amount of computer memory, or many steps in a program, were avoided as far as possible, or kept to a minimum. The present work is a greatly revised version of the former one. It is, in fact, a completely new book. The subjects have been expanded and the content has been improved. Changes were needed to take into account new resolutions of the International astronomical Union, particularly the adoption of the new standard epoch J2000.0, while moreover I profited by the new planetary and lunar theories constructed at the Bureau des Longitudes, Paris. as Gerard Bodifee wrote in the Preface of my previous work: anyone who endeavours to make astronomical calculations has to be very familiar with the essential astronomical conceptions and rules and he must have sufficient knowledge of elementary mathematical techniques. as a matter of fact he must have a perfect command of his calculating machine, knowing all possibilities it offers the competent user. However, all these necessities don't suffice. Creating useful, successful and beautiful programs requires much practice. Experience is the mother of all science. This general truth is certainly valid for the art of programming. Only by experience and practice can one learn the innumerable tricks and dodges that are so useful and often essential in agood program. astronomical algorithms intends to be a guide for the (professional or amateur) astronomer who wants to do calculations. an algorithm (from the arabic mathematician al-Khltrezmi) is a set of rules for getting something done; for us it is a mathematical procedure, a sequence of reasonings and operations which provides the solution to a given problem. This book is not a general textbook on astronomy. The reader will find no theoretical derivations. Some definitions are kept to a minimum. Nor is this a textbook on mathematics or a manual for microcomputers. The reader is assumed to be able to use his machine properly. Except in a few rare cases, no programs are given in this book. The reasons are clear. a program is useful only for one computer language. Even if we consider BaSIC only, there are so many versions of this language that a given program cannot be used as such by everybody without making the necessary changes. Every calculator thus must learn to create his own programs. There is the added circumstance that the precise contents of a program usually depend on the specific goals of the computation, that are impossible to anticipate by anybody else. The few programs we give are in standard BaSIC. They can easily be converted into FORTRaN or any other programming language. Of course, in the formulae we still use the classical mathematical symbols and notations, not the symbolism used in program languages. For example, we write instead of SQR(a), or a (1 - e) instead of a * (I - E), or cos2x instead of COS (X)" 2 or cos(X) * * 2. The writing of a program to solve some astronomical problem will require a study of more than one chapter of this book. For instance, in order to create a program for the calculation of the altitude of the Sun for a given time on a given date at a given place, one must first convert the date and time to Julian Day (Chapter 7), then calculate the Sun's longitude for that instant (Chapter 25), its right ascension and declination (Chapter 13), the sidereal time (Chapter 12) and finally the required altitude of the Sun (Chapter 13). This book is restricted to the "classical", mathematical astronomy, although a few astronomy oriented mathematical techniques are dealt with, such as interpolation, fitting curves, and sorting data. But astrophysics is not considered at all. Moreover, it is clear that not all topics of mathematical astronomy could have been covered in this book. So nothing is said about orbit determination, occultations of stars by the Moon, meteor astronomy, or eclipsing binaries. For solar eclipses, the interested reader will find Besselian elements and many useful formulae in Elements of Solar Eclipses 1951 to 2200 by the undersigned (1989). Elements and formulae about transits of Mercury and Venus across the Sun's disk are provided in my Transits (1989). These two books are published by Willmann-Bell, Inc. The author wishes to express his gratitude to Dr. S. De Meis (Milan, Italy), to a. Dill (Germany), and to E. Goffin and C. Steyaert (Belgium), for their valuable advice and assistance. Jean Meeus Note to the second edition In this second edition several misprints and errors have been corrected. The principal change in the new edition is the addition of some material, such as expressions for the times of the stations of the planets (Chapter 36), a list of constants (appendix I), expressions for the heliocentric coordinates of the giant planets from 1998 to 2025 (appendix IV), and new chapters about the Jewish and Moslem Calendars, and the satellites of Saturn. J.M.

The Analytical Foundations of Celestial Mechanics

Abstract: FROM the beginning of civilization one need must make itself felt, namely, for some form of calendar. In turn, this gives rise to the primitive study of astronomy, involving some knowledge of the sun and the moon. When the planets are added in the next stage, the astronomer needs an ephemeris or almanac ; the modern Nautical Almanac, with its perfection within narrow limits, is the final outcome. There have been many stages on the road, and some apparent interruptions. But the urge has always been the same, essentially a practical one. The Analytical Foundations of Celestial Mechanics By Aurel Wintner. (Princeton Mathematical Series, No. 5.) Pp. xii + 448. (Princeton, N.J.: Princeton University Press; London: Oxford University Press, 1941.) 36s. net.

The Black Cloud

Abstract: This is a 1959 classic 'hard' science-fiction novel by renowned Cambridge astronomer and cosmologist Fred Hoyle. It tracks the progress of a giant black cloud that comes towards Earth and sits in front of the sun, causing widespread panic and death. A select group of scientists and astronomers - including the dignified Astronomer Royal, the pipe smoking Dr. Marlowe and the maverick, eccentric Professor Kingsly - engage in a mad race to understand and communicate with the cloud, battling against trigger happy politicians. In the pacy, engaging style of John Wyndham and John Christopher, with plenty of hard science thrown in to add to the chillingly credible premise (he manages to foretell Artificial Intelligence, Optical Character Recognition and Text-to-Speech converters), Hoyle carries you breathlessly through to its thrilling end.

The Age of Wonder: How the Romantic Generation Discovered the Beauty and Terror of Science

Abstract: Richard Holmes, prize-winning biographer of Coleridge and Shelley, explores the scientific ferment that swept across Britain at the end of 18th century in his ground-breaking new biography 'The Age of Wonder'. 'The Age of Wonder' is Richard Holmes's first major work of biography in over a decade. It has been inspired by the scientific ferment that swept through Britain at the end of the eighteenth century, 'The Age of Wonder' and which Holmes now radically redefines as 'the revolution of Romantic Science'. The book opens with Joseph Banks, botanist on Captain Cook's first Endeavour voyage, stepping onto a Tahitian beach in 1769, hoping to discover Paradise. Many other voyages of discovery swiftly follow, while Banks, now President of the Royal Society in London, becomes our narrative guide to what truly emerges as an Age of Wonder. Banks introduces us to the two scientific figures that dominate the book: astronomer William Herschel and chemist Humphry Davy.Herschel's tireless dedication to the stars, assisted (and perhaps rivalled) by his comet-finding sister Caroline, changed forever the public conception of the solar system, the Milky Way galaxy and the meaning of the universe itself. Davy first shocked the scientific community with his near-suicidal gas experiments in Bristol, then went on to save thousands of lives with his Safety Lamp and established British chemistry as the leading professional science in Europe. But at the cost, perhaps, of his own heart. Holmes proposes a radical vision of science before Darwin, exploring the earliest ideas of deep time and deep space, the creative rivalry with the French scientific establishment, and the startling impact of discovery on great writers and poets such as Mary Shelley, Coleridge, Byron and Keats. With his trademark sense of the human drama, he shows how great ideas and experiments are born out of lonely passion, how scientific discoveries (and errors) are made, how intense relationships are forged and broken by research, and how religious faith and scientific truth collide.The result is breathtaking in its originality, its story-telling energy, and not least, in its intellectual significance.

Coming of Age in the Milky Way

Abstract: Popular science with witty anecdotes that lighten the intellectual load, integtrated with scientific ideas, and philosophical and religious contexts. From Aristotle to the Big Bang, from the music of the spheres to the unimaginable ancient light of a quasar, this is the story of man's long search for an understanding of cosmic space and time. He relates Kepler struggling to define the orbit of Mars, Galileo locked under house arrest for offending the Church, William Herschel plumbing deep in space in his study of galaxies, Murray Gell-Mann plotting the particles inside protons and neutrons. Written by a professional astronomer, he aims to be accessible to the general reader. He has also written "The Red Limit" and has received a number of awards for his work and teaches science writing and astronomy at the Univesity of Californai, Verkeley.