Alien Skies: A Travelogue of the Universe

719 Pages·2016·94.49 MB·English

by  Mario Mateo

ALIEN SKIES
A Travelogue of the Universe
First Edition
By Mario Mateo
University of Michigan - Ann Arbor
cognellcf JSSKs
Bassim Hamadeh, CEO and Publisher
Kassie Graves, Director of Acquisitions
Jamie Giganti, Senior Managing Editor
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Sean Adams, Project Editor
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Chelsey Schmid, Associate Editor
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Printed in the United States of America
ISBN: 978-1-5165-0632-3 (pbk) / 978-1-5165-0633-0 (br)
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CONTENTS
ACKNOWLEDGMENTS XI
FOREWORD XIII
DESTINATION 1 : THE MOON:
OUR FIRST STEP OFF EARTH
1.1 In Search of Alien Skies 1
1.2 The Sky from Home 3
1.3 Our First Step 11
DESTINATION 2: THE VIEW FROM MARS
2.1 Terror and Fear in the Sky of Mars 21
2.2 The Riddle of Planetary Motion 28
2.3 Kepler’s Third Law: The Triumph of Simplicity 34
DESTINATION 3: THE SKY FROM EARTH:
A LAST LOOK FROM HOME
3.1 Preparations for a Long Voyage 43
3.2 Navigating in the Sky 44
3.3 The Distances of Stars: Stellar Parallax 53
DESTINATION 4: THE SKY FROM a CENTAURI
4.1 A Familiar Light in an Alien Sky 61
4.2 An Alien Light in an Alien Sky 67
4.3 A Faint Light in an Alien Sky 73
DESTINATION 5: THE 'EMPTY' SKY OF DEEP
SPACE: AT ‘ANTI-CENTAURI’
5.1 No Place in Particular 81
5.2 The Matter of'Empty Space' 83
5.3 Seeing the Invisible: Neutral Hydrogen and 21-cm Radiation 91
5.4 Hot Matter in Cold Space 98
DESTINATION 6: THE ORION NEBULA
6.1 Secrets of a Celestial Hunter 103
6.2 The Bright Sky of the Orion Nebula 106
6.3 The Dark Clouds of the Orion Nebula 115
6.4 The Stars of the Orion Nebula 127
DESTINATION 7: EXTRASOLAR PLANETARY
SYSTEMS: 51 PEGASI
7.1 A Star in Pegasus 137
7.2 What We Really Came to See 140
7.3 The Properties and Formation of Planetary Systems 149
7.4 Do Planets Imply Life? 154
DESTINATION 8: THE PLEIADES
8.1 A Sky Without Night 163
8.2 The Stars of the Pleiades Cluster 167
8.3 The Spectra of Stars 172
8.4 Why Do Stars Shine? 180
DESTINATION 9: EXPLORING THE MILKY WAY
9.1 Our Home’s Home 193
9.2 Rising up from the Milky Way 197
9.3 The Galactic Disk 202
9.4 Through the Galactic Plane 207
9.5 Rotation of the Galaxy 211
9.6 A Summary of a Fantastic Journey 219
DESTINATION 10: INWARD BOUND:
THE GALACTIC CENTER
10.1 To the Galactic Center: Through the Inner Galactic Disk 227
10.2 To the Galactic Center: From the Disk to the Bulge 233
10.3 A Strange New World: The Galactic Center 238
DESTINATION 11: A BLAZING SKY OF STARS:
THE GLOBULAR CLUSTER M 92
11.1 Summer in Paris 251
11.2 The Sky Ablaze: The View from M 92 254
11.3 Stellar Death 261
11.4 White Dwarfs: The Corpses of Low-Mass Stars 266
11.5 A Window to an Ancient Past 272
11.6 A Different Way to Stay Together 274
DESTINATION 12: THE MAGELLANIC CLOUDS:
THE NEAREST GALAXIES
12.1 The Magellanic Clouds: Beyond the Galaxy 281
12.2 The Case of the Missing White Dwarfs 286
12.3 The Evolution of High-Mass Stars 290
12.4 Witnessing High-Mass Stellar Evolution 296
12.5 Victory of a Relentless Force 303
DESTINATION 13: THROUGH THE HEART OF
DARKNESS: THE GALACTIC HALO
13.1 The Lonely Outskirts of the Galaxy 311
13.2 Dark Matter in the Galactic Halo 317
13.3 The Structure of the Galactic Halo 325
DESTINATION 14: THE NEARBY SPIRAL
GALAXIES M 31 AND M 33
14.1 Leaving Our Galaxy Behind 335
14.2 Cepheid Variable Stars: A New Way to Estimate Extragalactic Distances 339
14.3 The Galaxy, M 31, and M 33: The Closest Spiral Galaxies 344
14.4 What Are Spiral Arms? 348
14.5 The Peculiar Role of Dark Matter 352
14.6 The Local Group 354
DESTINATION 15: THE GIANT ELLIPTICAL
GALAXY MAFFEI 1
15.1 Beyond the Local Group 363
15.2 Maffei 1: A Giant Elliptical Galaxy 368
15.3 Classifying Galaxies: The Hubble Sequence 377
DESTINATION 16: THE VIRGO CLUSTER:
A SKY OF GALAXIES
16.1 The Virgo Cluster of Galaxies 389
16.2 Galaxies in Collision 394
16.3 The Hubble Law 402
16.4 The Dark Matter of the Virgo Cluster 408
DESTINATION 17: THERE’S SOMETHING
STRANGE HERE: THE SEYFERT GALAXY M 77
17.1 The Monster in the Middle 417
17.2 The Two Faces of the Monster 424
17.3 The Name of the Monster 427
17.4 Einstein's Legacy: An Introduction 433
17.5 Einstein's Legacy: Getting Personal 438
17.6 The Maw of the Monster 442
17.7 In Memoriam 444
DESTINATION 18: THE BOOTES VOID
18.1 Mapping the Distribution of Galaxies 449
18.2 The Dark, Lumpy Universe 456
18.3 'Light' in the Darkness: The Cosmic Microwave Background 463
DESTINATION 19: BACK IN TIME TO A DISTANT
GALAXY CLUSTER
19.1 Navigating Space and Time 471
19.2 Telling Time in the Universe 473
19.3 What Kind of Universe Do We Inhabit? 483
19.4 MS1054-0321: A Galaxy Cluster at z = 0.8 490
DESTINATION 20: HIGH REDSHIFT GALAXIES:
THE YOUNG AND RESTLESS UNIVERSE
20.1 The Galaxies of the Early Universe 499
20.2 The Golden Era of Galaxy Formation 504
DESTINATION 21: QUASARS AT THE DAWN OF
GALAXY FORMATION
21.1 Young Galaxies and 'False Stars’ 513
21.2 Quasars: Extreme Active Galactic Nuclei 516
21.3 Quasars in the Early Universe: Implications for Galaxy Formation 530
DESTINATION 22: THE DARK AGES
22.1 A Simpler Universe 537
22.2 The Problem with Being Smooth, Part 1: Why So Lumpy Now? 541
22.3 The Problem with Being Smooth, Part 2: Why Is the CMB So Uniform? 545
DESTINATION 23: THE ERA OF RECOMBINATION
23.1 Into the Fog 553
23.2 Lifting the Veil: The Era of ‘Re’-combination 558
23.3 The Seeds of Creation 565
DESTINATION 24: THE FIRST ELEMENTS IN THE
UNIVERSE
24.1 The Evolution of the Chemical Elements: Getting Started 573
24.2 Fusion in an Expanding Universe 579
DESTINATION 25: TO A TIME BEFORE TIME
25.1 The Genesis of Matter 587
25.2 The Genesis of Physical Forces and the Inflation Era 596
25.3 As Far as We Can Go: The Planck Time 602
APPENDICES
Appendix A Summary of Destinations 611
Appendix B Units, Symbols, and Conversion Factors 621
Appendix C Constants 627
Appendix D Mathematical Formulae 629
Appendix E Basic Data for Selected Planets
and Dwarf Planets of the Solar System 641
Appendix F The Constellations of Earth's Sky 643
Appendix G The Natural Chemical Elements 649
FIGURE CREDITS 653
INDEX 669