Starlight (eBook)

Acknowledgements 5
Contents 6
About the Author 7
A River of Starlight 8
Starlight by Numbers 13
Large Numbers and Small Numbers 14
The Rule of Indices 15
The Rule of Indices for All Indices 17
Working with Powers of Ten 18
Scientific Notation 19
Star Distances by Numbers 22
Key Points 27
From Light to Starlight 29
Let There Be (an Idea About) Light 30
Natures Color Palette The Electromagnetic Spectrum 36
How to Measure the Wavelength of Light 40
The Spectrum, the Whole Spectrum, and Nothing but the Spectrum 43
A Brief Note on the Spectroscope 45
Light and Energy 46
Let There Be Another Idea About Light 48
The Parable of the Two Tables Blackbody Radiation 52
The Blackbody Spectrum 57
The Parable of the Blackbody and the Star 60
Key Points 62
Space -- The Great Radiation Field 64
Rivers of Energy 64
Measuring the Radiation Field 65
Sunlight Is Intense But Starlight Is Not 70
How Many Light Bulbs Must You Screw in to Make a Star? 72
From Flux to Flux Ratio to Magnitude 78
How to Calculate Magnitudes 82
Fixing the Magnitude Scale 84
Absolute Magnitude A Measure of Stellar Luminosity 86
Key Points 89
A Multitude of Magnitudes for the Colors of Starlight 91
Blackbody Stars 64
From Theories of Physics to Astronomical Observations 65
Star Partners Color and Magnitude 70
Color and Blackbody Temperature 72
Measuring Effective Temperatures for Real Stars 78
Yet Another Magnitude 82
Sorting Out Stellar Spectra 84
The HertzsprungRussell Diagram 86
Using the HR Diagram Template 89
A Different Kind of HR Diagram 117
Conclusion 118
Key Points 119
The Photons Must Get Through -- Radiative Transfer 122
Absorption The Photons Get Taken Out 64
The Photon Gets a Second Chance (and Maybe More) Scattering 65
New Photons for Old Emission 70
Symbiotic Nebulae An Illustration of Optical Depth in Action 72
Key Points 78
First Look Inside a Star -- The Atmosphere 147
Simple Radiative Transfer in the Photosphere 64
The Chromosphere and the Corona 65
Yet Another Kind of HR Diagram 70
A Photosphere Full of Hydrogen Atoms 72
The Hydrogen Absorption Lines 78
The Ups and Downs of a Hydrogen Atom 82
The Ups and Downs of a Hydrogen Atom in a Photosphere 84
The Temperature of Vega 86
Return to the ColorColor Diagram 89
Model Atmospheres for Stars 117
Key Points 118
Deep Inside a Star 176
Hot Gas The Basics 64
From a Cylinder of Gas to the Structure of a Star 65
The Principles of Stellar Structure 70
From a Cylinder of Gas to Stellar Pulsation 72
Cepheid Variable Stars The Other Story 78
How to Make a Star Pulsate 82
Yet Another Gas Cylinder Experiment 84
Exciting Stellar Pulsation 86
The Right Kind of Gas in the Right Kind of Star 89
Details, Details 117
From a Cylinder of Gas to a Red Giant Star 118
Convection in Stars 119
The Stellar Core Source of the River of Starlight 207
Nuclear Fusion in Stars The Details 210
The CNO Cycle 213
Key Points 214
In the Space Between Stars 216
Winds from the Stars 64
Stardust 65
When the Galaxy Shrank 70
Space Dust 72
The Dimming of Starlight 78
Through the Atmosphere 82
Key Points 84
A Star Story 0 10 Billion Years in the Making 235
The Middle of the Story Life on the Main Sequence 235
The Beginning of the Story From Atoms to Stars 239
The End of the Story Life After the Main Sequence 245
Stellar Evolution in Action 253
Old Stars, Young Stars, and New Stars from Old 257
The Legacy of Starlight 259
Conclusion 260
Key Points 262
Appendix 1: The Greek Alphabet 264
Appendix 2: Astronomical and Physical Units and Constants 265
Important Units 266
Constants 267
Physical Constants 267
Astronomical Constants 267
Appendix 3: The Doppler Effect 268
Index 270