An Introduction to Distance Measurement in Astronomy

by de Grijs, Richard

• ISBN13: 9781119978176
• ISBN10: 1119978173
• Edition: 1st
• Format: eBook
• Copyright: 2011-09-06
• Publisher: Wiley

Summary

Distance determination is an essential technique in astronomy, and is briefly covered in most textbooks on astrophysics and cosmology. It is rarely covered as a coherent topic in its own right. When it is discussed the approach is frequently very dry, splitting the teaching into, for example, stars, galaxies and cosmologies, and as a consequence, books lack depth and are rarely comprehensive. Adopting a unique and engaging approach to the subject An Introduction to distance Measurement in Astronomy will take the reader on a journey from the solar neighbourhood to the edge of the Universe, discussing the range of distance measurements methods on the way. The book will focus on the physical processes discussing properties that underlie each method, rather than just presenting a collection of techniques. As well as providing the most compressive account of distance measurements to date, the book will use the common theme of distance measurement to impart basic concepts relevant to a wide variety of areas in astronomy/astrophysics. The book will provide an updated account of the progress made in a large number of subfields in astrophysics, leading to improved distance estimates particularly focusing on the underlying physics. Additionally it will illustrate the pitfalls in these areas and discuss the impact of the remaining uncertainties in the complete understanding of the Universes at large. As a result the book will not only provide a comprehensive study of distance measurement, but also include many recent advances in astrophysics.

Table of Contents

Preface xi

1 The Importance of Astrophysical Distance Measurements 1

1.1 The Distance to the Galactic Centre 2

1.1.1 Early Determinations of R0 3

1.1.2 Modern Results 6

1.2 The Distance to the Large Magellanic Cloud 11

1.3 Benchmarks Beyond the Magellanic Clouds: the 3D Universe on Large(r) Scales 15

Bibliography 22

2 The Solar Neighbourhood 31

2.1 Geometric Parallax Measurements 31

2.1.1 Trigonometric Parallax 31

2.1.2 Astrometric Advances: Space-Based Missions and Interferometry 33

2.1.3 Secular and Statistical Parallaxes: Moving Groups Method 39

2.2 Dynamical Parallax 42

2.2.1 Mass–Luminosity Relations 46

2.3 Spectroscopic and Photometric Parallaxes 50

Bibliography 55

3 From the MilkyWay to the Local Group 63

3.1 Basic Stellar Physics as the Key to Understanding Distance Measurements

to Local Group Galaxies 63

3.1.1 Stellar Evolution Through the Hertzsprung–Russell Diagram 63

3.1.2 From Two to Multiple Stellar Populations 68

3.2 Open and Globular Cluster Hertzsprung–Russell Diagrams 70

3.2.1 Main-Sequence and Subdwarf Fitting 70

3.2.2 Red Clump Stars 72

3.2.3 The (Zero-Age) Horizontal Branch Level 74

3.3 Giants and Supergiants as Standard Candles 76

3.3.1 The Tip of the Red Giant Branch 76

3.3.2 The Red Giant Branch Bump 78

3.3.3 Supergiants as Standard Candles 80

3.4 White Dwarf Sequences 83

3.5 Period–Density Relations 84

3.5.1 The Baade–Wesselink Method 85

3.5.2 Classical Cepheid Variables 87

3.5.3 Mira Variables 90

3.5.4 W Virginis and Other ‘Population II’ Cepheids 93

3.5.5 RR Lyrae Stars 95

3.5.6 Dwarf and Anomalous Cepheids 97

3.6 Novae as Standard Candles 98

3.7 Geometric Methods 100

3.7.1 Planetary Nebula Expansion Parallaxes 101

3.7.2 Supernova Light Echoes 102

3.7.3 Eclipsing Binary Stars 106

3.7.4 Maser-Based Distance Determinations 108

3.8 Pulsars: Distance Measurements Outside the ‘Classical’ Wavelength Range 110

Bibliography 114

4 Reaching Virgo Cluster Distances and Beyond 135

4.1 The Hubble Space Telescope Key Project 135

4.2 Surface Brightness Fluctuations 136

4.3 The Globular Cluster Luminosity Function 140

4.3.1 Elliptical Versus Spiral Galaxy GCLFs 141

4.3.2 The Stellar Population Mix 144

4.3.3 GCLF and GCMF Universality Through Dynamical Evolution 144

4.4 The Planetary Nebulae Luminosity Function 148

4.4.1 Applicability 149

4.4.2 Physical Basis 150

4.5 The Tully–Fisher Relation 151

4.5.1 Wavelength Dependence 152

4.5.2 The Scatter in the Tully–Fisher Relation 154

4.6 Distance Indicators Specific to Elliptical Galaxies 156

4.7 The Colour–Magnitude Relation 161

4.8 Hii Regions as Distance Indicators? 164

Bibliography 165

5 From Nearby Galaxy Clusters to Cosmological Distances 175

5.1 Cosmological Redshifts 175

5.1.1 Determination of the Current Expansion Rate of the Universe 175

5.1.2 Redshift Surveys and Peculiar Velocities 176

5.1.3 The Prevailing Cosmological Model 179

5.2 Supernovae as Beacons 186

5.2.1 Type Ia Supernovae 188

5.2.2 Type II-P Supernovae 197

5.2.3 A Link to Gamma-Ray Bursts as Standard Candles? 207

5.3 Indirect Techniques to Measure H0 210

5.3.1 Gravitational Lensing: Time Delays 210

5.3.2 The Sunyaev–Zel’dovich Effect 215

5.3.3 Anisotropies in the Cosmic Microwave Background 222

5.3.4 The Drive for Improved Accuracy 225

Bibliography 227

6 Systematic Uncertainties and Common Pitfalls 243

6.1 Common Biases 244

6.1.1 Extinction: Spatial Distribution and Wavelength Dependence 244

6.1.2 Parallaxes: Lutz–Kelker Bias 246

6.1.3 Malmquist Bias 251

6.2 High Versus Low Values of the Hubble Constant: Science or Philosophy? 255

Bibliography 259

7 Promises and Prospects 267

7.1 The Way Forward: Where Are Significant Gains Achievable? 267

7.2 The Pleiades Distance Controversy 270

7.3 X-Ray Scattering Haloes 273

7.4 Standard Sirens: Listening to Gravitational Waves 276

7.5 Three-Dimensional Mapping of Redshifted Neutral Hydrogen 280

7.6 The Present-Day Distance Ladder 283

Bibliography 285

Glossary 293

Figure Credits 305

Index 309