Description:

Astronomy: A Physical Perspective Marc L. Kutner This fully revised and updated text is a comprehensive introduction to astronomical objects and phenomena. By applying some basic physical principles to various situations students will learn how to relate everyday physics to the astronomical world. Starting with simple objects, the text contains thorough explanations of how and why astronomical phenomena occur and how astronomers collect and interpret information about stars, galaxies, and the Solar System. The text examines properties of stars, star formation and evolution; neutron stars and black holes; nature of galaxies; structure of the universe. It also looks at past present and future states of the universe; final chapters use concepts developed to study the Solar System its formation possibility finding other planetary systems search for extraterrestrial life. This comprehensive text contains useful equations chapter summaries, worked examples and end-of-chapter problem sets. Suitable for undergraduate students taking a first course in astronomy it assumes basic knowledge of physics with calculus. Marc L. Kutner obtained his doctorate in physics from Columbia University in 1972. He has been a Visiting Scientist in the Department of Astronomy at the University of Texas at Austin since 1998 prior to which he was Professor in the Department of Physics and Astronomy at Rensselaer Polytechnic Institute, New York and Visiting Scientist at the National Radio Observatory Tucson Arizona His main area of research involves use of radio astronomy to study star formation in the Milky Way and other galaxies. He has also done some research in cosmology. Contents List of abbreviations used in figure credits Preface 1 Introduction 1.1 An understandable universe 1.2 The scale of the universe Part I Properties of ordinary stars 2 Continuous radiation from stars 2.1 Brightness of starlight 2.2 The electromagnetic spectrum 2.3 Colors of stars 2.3.1 Quantifying color 2.3.2 Blackbodies 2.4 Planck’s law and photons 2.4.1 Planck’s law 2.4.2 Photons 2.5 Stellar colors 2.6 Stellar distances 2.7 Absolute magnitudes Chapter summary Questions Problems Computer problems 3 Spectral lines in stars 3.1 Spectral lines 3.2 Spectral types 3.3 The origin of spectral lines 3.3.1 The Bohr atom 3.3.2 Quantum mechanics 3.4 Formation of spectral lines 3.4.1 Excitation 3.4.2 Ionization 3.4.3 Intensities of spectral lines 3.5 The Hertzprung–Russell diagram Chapter summary Questions Problems Computer problems 4 Telescopes 4.1 What a telescope does 4.1.1 Light gathering 4.1.2 Angular resolution 4.1.3 Image formation in a camera Page xv xvii 1 1 3 7 9 9 10 12 12 13 15 15 16 17 18 20 21 21 22 23 25 25 26 27 28 31 32 32 33 34 36 38 39 39 40 vi CONTENTS 4.2 Refracting telescopes 45 4.3 Reflecting telescopes 46 4.4 Observatories 53 4.4.1 Ground-based observing 53 4.4.2 Observations from space 56 4.5 Data handling 58 4.5.1 Detection 58 4.5.2 Spectroscopy 60 4.6 Observing in the ultraviolet 62 4.7 Observing in the infrared 63 4.8 Radio astronomy 68 4.9 High energy astronomy 75 Chapter summary Questions Problems Computer problems 5 Binary stars and stellar masses 83 5.1 Binary stars 83 5.2 Doppler shift 84 5.2.1 Moving sources and observers 84 5.2.2 Circular orbits 86 5.3 Binary stars and circular orbits 87 5.4 Elliptical orbits 91 5.4.1 Geometry of ellipses 91 5.4.2 Angular momentum in elliptical orbits 91 5.4.3 Energy in elliptical orbits 93 5.4.4 Observing elliptical orbits 93 5.5 Stellar masses 94 5.6 Stellar sizes 96 Chapter summary Questions Problems Computer problems 6 The Sun: a typical star 101 6.1 Basic structure 101 6.2 Elements of radiation transport theory 101 6.3 The photosphere 105 6.3.1 Appearance of the photosphere 105 6.3.2 Temperature distribution 107 6.3.3 Doppler broadening of spectral lines 108 6.4 The chromosphere 109 6.5 The corona 110 6.5.1 Parts of the corona 110 6.5.2 Temperature of the corona 112 6.6 Solar activity 113 6.6.1 Sunspots 113 6.6.2 Other activity 116 Chapter summary Questions Problems Computer problems Part II Relativity 7 Special relativity 7.1 Foundations of special relativity 7.1.1 Problems with electromagnetic radiation 7.1.2 Problems with simultaneity 7.2 Time dilation 7.3 Length contraction 7.4 The Doppler shift 7.4.1 Moving source 7.4.2 Moving observer 7.4.3 General result 7.5 Space-time 7.5.1 Four-vectors and Lorentz transformation 7.5.2 Energy and momentum Chapter summary Questions Problems Computer problems 8 General relativity 8.1 Curved space-time 8.2 Principle of equivalence 8.3 Tests of general relativity 8.3.1 Orbiting bodies 8.3.2 Bending electromagnetic radiation 8.3.3 Gravitational redshift 8.3.4 Gravitational radiation 8.3.5 Competing theories 8.4 Black holes Relativity, 143 Orbiting Solar Observatory 7 (OSO 7), 111 organic compounds, 450 origin of comets, 527 origin of dipole anisotropy, 402 INDEX 577 origin of life, 537–49 origin of the Moon, 474 origin of Solar System, 429 origin of spectral lines, 27 Orion Nebula, 67, 269, 287, 288, 289 Orion region, 287–9, 287 CO map, 269 energetic flow, 289 giant molecular clouds (GMCs), 269, 287 HII regions, 287 Horsehead Nebula, 239, 288 OB association, 287 Orion Nebula, 67, 269, 287, 288, 289 oscillating universe, 384, 384 other planetary systems, see extrasolar planets outer planets, 429, 497–519 atmospheres, 500–5 basic features, 497–500 distance to, 434 Galilean satellites, 512 interiors, 506, 506 moons, 512–19 ring system, 506–12 overcoming the fusion barrier, 162–4 ozone (O3), 450 ozone hole, 462 ozone layer, 462 p–e–p reaction, 174 p–p chain, 165 pair production and black hole, 151 panoramic quality of photographic plate, 58 paraboloid, 48 parallax spectroscopic, 38 parallax angle, 18 parallax measurements, 19 paramagnetic material, 243 parameters of cosmological models, 385 parity, 413 parsec, 19 particle orbits Saturn, 507–8 particle–antiparticle pairs, 418 Pathfinder landing site Mars, 488 pattern speed explanations of spiral structure, 327–8 Pauli exclusion principle, 186, 197, 414 pc see parsec peculiar galaxies, 322 penumbra, 113, 113, 437 Penzias Arno, 251, 398, 399 perihelion comets, 527 of Mercury advance of, 144 period changes in pulsars, 203–5 period–luminosity relation for Cepheids, 182 PG115+080 gravitational lensed quasar, 369 Phobos, 494, 494 photocells, 16 photoelectric devices, 58 photoelectric effect, 16, 244–45 photographic plate, 58 panoramic quality, 58 photomultiplier, 59 photon, 16–17, 28, 412, 415, 418 photon diffusion, 177 photon number density primordial, 408 photon sphere, 150 photosphere, 101, 105–9 base temperature, 109 photosynthesis on early Earth, 540 physics of big and small merging, 417–22 pion, 411–12 Pioneer spacecraft Jupiter, 497 Pioneer Venus Orbiter, 480 pixel, 58 plages, 117 Planck Max, 16 Planck constant, 16 Planck function cosmic background radiation, 397 Planck time, 417 Planck’s law, 15–16 planetary nebulae, 183–5 lines of sight through, 185 planets see also under individual planet names planitesimals, 539–40 plant life on early Earth, 540 plasma, 395 plate tectonics, 450–2 Pleiades, 221, 222 Pluto, 523–4, 524 polar caps Mars, 480, 489–90 polarization, 242 polycyclic aromatic hydrocarbons (PAHs), 243 population I stars, 232 population II stars, 232 population inversion, 280–1 populations in cluster of stars, 232 level, 33, 255–7, 399–401 positron, 162 postulate of special relativity, 125 potential energy for globular cluster, 227 power absorbed by Earth, 453 power law spectrum, 197 power radiated by Earth, 453 Poynting Robertson drag, 511 Poynting Robertson effect, 540 pre-biotic soup origin of life, 542 precession Earth, 468–9, 468 pressure distribution Earth, 455–7, 456 pressure in a degenerate gas, 187 prime focus, 48 blockage, 48 primordial abundances, 409 principle of equivalence, 140–3, 140 probability of a nuclear reaction, 164 problems in cosmology, 417–19 problems with simultaneity, 127 Procyon, 27 Project Gemini, 55, 56 prominences, 117, 118 proper length, 130 proper motion in moving cluster, 221 proper time, 128 proportional counters, 75 proteins and origin of life, 542 proton primordial, 407–8 proton decay, 416–17 proton rest energy, 161 proton–proton chain, 165 protostars, 272–4 protostellar cores, 286, 287 Proxima Centauri, 20 pseudo-force, 142 asteroids Earth, 463–4 Ptolemy, 9, 430 pulsars, 199–205 Crab Pulsar, 205 energy loss, 204 glitches, 203, 204 magnetic field Ключевые слова: hydrogen, dirty snowball, ir nm, au, global warming, causally connected, telescope, magnitude, yr, fn fn, pc, field, gravitational binding, rotation, virial theorem, wa, electrical attraction, dv, space, mb, center, atmosphere, everything else, range, artists conception, big crunch, amino acid, force, terra ishta, close, relativity, fi, nobel prize, velocity, optical counterpart, mass, black hole, radiation, electric repulsion, equation, moon, hopeless task, harlow shapley, cloud, type, white dwarf, coulomb repulsion, elastic medium, stellar, chi persei, mauna kea, waveparticle duality, electron, chapter, study, process, region, angular, matter, interstellar, observation, kao, higher, period, electrical repulsion, jupiter, problem, spectral, national atmospheric, thermodynamic equilibrium, olympus mons, main sequence, mn, star, roman numeral, dadt, spectroscopic parallax, standard candle, source, magnetic, sulfuric acid, ambipolar diffusion, distribution, angular magnification, visiting scientist, motion, cluster, case, doe, atom, silla, light, dr, larger, interstellar medium, luminosity, difference, magnetic monopoles, object, crab nebula, speed, fourier transform, universe, ori, theory, large, form, distance, high, number, photon, seismic disturbance, particle, thermal equilibrium, vr, structure, bell laboratories, work, scale, rc rp, non-zero, nh, point, gm, radio, reection nebula, direction, alexandria egypt, nuclear processing, orbit, galaxy, constant, vx px, ha, ehkt, moving, gravitational, size, fs, model, area, earth, time, panoramic quality, density, proton, white oval, magellanic clouds, nm, dt, tarantula nebula, solar, ln, wavelength, molecule, small, emission, level, year, trigonometric parallax, dynamical entity, radius, dust, change, shift, ring, cm, nuclear attraction, pressure, hole, olberss paradox, long, optical, molecular, ww ii, sun, cerro paranal, big bang, spiral, formation, radar mapping, rate, remote sensing, everest, energy, gas, quantum mechanic, spectrum, temperature, measure, angular scale, nucleus, atmospheric scientist, cerro pachon, stellar masses, hydrostatic equilibrium, einstein, planet, place, black, traffic jam, result, neutron, image, surface, material, gmm