Moore The Amateur Astronomer

12th Auflage 2006
ISBN: 978-1-84628-286-7
Verlag: Springer
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, 293 Seiten

This 2000 Edition of Sir Patrick Moore's classic book has been completely revised in the light of changes in technology. Not only do these changes include commercially available astronomical telescopes and software, but also what we know and understand about the universe. There are many new photographs and illustrations. Packs a great deal of valuable information into appendices which make up almost half the book. These are hugely comprehensive and provide hints and tips, as well as data (year 2000 onwards) for pretty well every aspect of amateur astronomy. This is probably the only book in which all this information is collected in one place.

Autoren/Hrsg.

Moore, Patrick

Inhaltsverzeichnis

1;Publisher’s Note;5
2;Preface to the First Edition;7
3;Preface to the Twelfth Edition;9
4;Contents;11
5;1 Astronomy as a Hobby;14
6;2 The Unfolding Universe;16
7;3 Telescopes and Observatories;30
8;4 The Solar System;44
9;5 The Sun;54
10;6 The Moon;64
11;7 Occultations and Eclipses;80
12;8 Aurorae and the Zodiacal Light;90
13;9 The Nearer Planets;96
14;10 The Outer Planets;106
15;11 Comets and Meteors;118
16;12 The Stellar Sky;132
17;13 The Nature of a Star;140
18;14 Double Stars;146
19;15 Variable Stars;152
20;16 Star Clusters and Nebulae;162
21;17 Galaxies;172
22;18 Beginnings and Endings;180
23;Appendicies;182
23.1;1 Planetary Data;182
23.2;2 Planetary Satellites of Magnitude 14.5 or Brighter;183
23.3;3 Minor Planet Data;184
23.4;4 Elongations and Transits of the Inferior Planets;185
23.5;5 Map of Mars;187
23.6;6 Jupiter: Transit Work;189
23.7;7 Saturn: Intensity Estimates;191
23.8;8 Forthcoming Eclipses;192
23.9;9 The Limiting Lunar Detail Visible with Different Apertures;193
23.10;10 The Lunar Maps;194
23.11;11 Some of the More Important Annual Meteor Showers;206
23.12;12 The Constellations;207
23.13;13 Proper Names of Stars;210
23.14;14 Stars of the First Magnitude;217
23.15;15 Standard Stars for Each Magnitude;218
23.16;16 The Greek Alphabet;220
23.17;17 Stellar Spectra;221
23.18;18 Limiting Magnitudes and Separations for Various Apertures;222
23.19;19 Angular Measure;223
23.20;20 Test Double Stars;224
23.21;21 Extinction;225
23.22;22 Bright Novae;226
23.23;23 Messier’s Catalogue;228
23.24;24 The Caldwell Catalogue;231
23.25;25 The Star Maps;234
23.26;Map;235
23.26.1;Map I. Key Map: Ursa Major ( The Great Bear);235
23.26.2;Map II. Key Map: Orion;237
23.26.3;Map III. Ursa Major, Ursa Minor, Draco, Cepheus, Camelopardus;239
23.26.4;Map IV. Orion, Lepus, Eridanus, Taurus, Cetus, Auriga, Columba, Caelum, Fornax;242
23.26.5;Map V. Gemini, Cancer, Canis Major, Canis Minor, Monoceros, Hydra;246
23.26.6;Map VI. Leo, Virgo, Coma Berenices, Corvus, Crater, Leo Minor;250
23.26.7;Map VII. Cassiopeia, Cepheus, Lacerta, Perseus, Andromeda, Lynx, Triangulum;253
23.26.8;Map VIII. Cygnus, Lyra, Sagitta, Vulpecula, Delphinus, Equuleus, Capricornus, Aquila, Sagittarius, Scutum, Serpens, Aquarius;256
23.26.9;Map IX. Boötes, Corona Borealis, Hercules, Serpens, Ophiuchus, Libra, Scorpio;261
23.26.10;Map X. Pegasus, Andromeda, Pisces, Triangulum, Aries, Cetus, Aquarius, Sculptor, Pisces Australis;265
23.26.11;Map XI. Key Map: Crux Australis ( The Southern Cross);268
23.26.12;Map XII. Key Map: Orion;271
23.26.13;Map XIII. Crux, Centaurus, Lupus, Circinus, Triangulum Australe, Norma, Ara, Telescopium, Sagittarius, Corona Australis, Scorpio;273
23.26.14;Map XIV. Carina, Vela, Puppis, Pyxis, Volans, Antila;277
23.26.15;Map XV. Octans, Apus, Musca, Chamaeleon, Mensa, Hydrus, Reticulum, Dorado, Pictor, Eridanus, Horologium;280
23.26.16;Map XVI. Pavo, Indus, Tucana, Grus, Phoenix, Microscopium;283
23.27;26 The Observation of Variable Stars;286
23.28;Binocular Variables;289
23.29;Telescopic Variables;293
23.30;27 Some Periodical Comets;298
23.31;28 Amateur Observatories;299
23.32;29 Astronomical Societies;301
23.33;30 Bibliography;302
24;Index;304

Leseproben

Chapter 15
Variable Stars (p.139-140)

Fortunately for us, our Sun is a steady, well-behaved star. It may have periods of unusual activity, when its disk is disturbed by spot-groups and flares, but at least its output of energy does not alter greatly over the lapse of hundreds of centuries. Other suns are not so quiescent. Some of them vary in brightness from day to day, even from hour to hour, either regularly or in an erratic manner.

They swell and shrink, and their temperatures change with their fluctuations, so that any planet circling round them would be subject to most uncomfortable changes of climate. Variable stars are important both to the professional and to the amateur, and the owner of a small instrument can do useful work, particularly as his telescope need not be so perfect as that of the lunar or planetary observer (though, of course, the better the telescope the better the results).

It is true that the regular variables of short period have been closely studied at the great observatories, but there are other stars which seem to delight in springing surprises, so that they need constant watching. Variable stars are of many types, but it is not difficult to give a general classification. First there are the eclipsing binaries, such as Algol in Perseus,which are not true "variables" at all, even though they do seem to alter in brightness.

Perhaps the most important of the true short-period variables are the Cepheids, so named because the star Delta Cephei is the best-known member of the class; the periods range from a few days up to six or seven weeks. Of much shorter period are the RR Lyrae stars, whose periods range between 30 hours and less than 2 hours. Then there are the long-period variables, usually Red Giants of great size and comparatively low temperature,with periods ranging from 70 days to over 2 years. Irregular variables, as their name suggests, behave in an unpredictable manner. Lastly come the violently explosive "temporary stars" or novae. There are several variables which can be followed without any telescope at all.

The most famous of these is Betelgeux, the Red Giant in Orion. It belongs to the irregular class, though there is a very rough period of from 4 to 5 years, and it changes in brightness from magnitude 0 down to 1, so that whereas it may sometimes almost equal the glittering Rigel it may at others be comparable with Aldebaran, the "Eye of the Bull;". The alterations are slow, but they become noticeable over a week or two, and the beginner who estimates the magnitude of Betelgeux every few days will soon be able to detect the fluctuations.

However, most of the interesting variables cannot be followed without a telescope or at least binoculars, since when near minimum they are below naked-eye visibility. Before coming to the proper variables, it will be of interest to say something about the "fake variables", or eclipsing binaries. These might well have been described in the chapter dealing with double stars, but since they do seem to change in brilliancy they come under the scope of the variable star enthusiast. The best-known of these "fakes" is Algol, which lies in the constellation of Perseus and is shown in Map VII. In mythology, Perseus was the hero who slew the fearful Gorgon, Medusa, whose glance turned the hardiest onlooker to stone, and it is fitting that Algol should mark the Gorgon’s severed head.