Understanding Our Universe (Fourth Edition)

Cover
Publisher’s Notice
Half-title Page
Title Page
Copyright
Dedication
Brief Table of Contents
Contents
AstroTours
Interactive Simulations
Astronomy in Action Videos
Preface
About the Authors
Half-title Page
1: Our Place in the Universe
1.1: Astronomy Creates a Universal Context
1.2: Science Is a Way of Viewing the World
1.3: Astronomers Use Mathematics to Find Patterns
Reading Astronomy News
Summary
Exploration: Scaling the Solar System
2: Patterns in the Sky—Motions of Earth and the Moon
2.1: Earth Spins on Its Axis
2.2: Revolution around the Sun Leads to Changes during the Year
2.3: The Moon’s Appearance Changes As It Orbits Earth
2.4: Shadows Cause Eclipses
Reading Astronomy News
Summary
Exploration: Phases of the Moon
3: Laws of Motion
3.1: Astronomers Have Studied the Motions of the Planets since Ancient Times
3.2: Galileo Was the First Modern Scientist
3.3: Newton’s Laws Govern Motion
3.4: Gravity Is a Force between Any Two Massive Objects
3.5: Orbits Are One Body “Falling around” Another
Reading Astronomy News
Summary
Exploration: Newtonian Orbits
4: Light and Telescopes
4.1: What Is Light?
4.2: Cameras and Spectrographs Record Astronomical Data
4.3: Telescopes Collect Light
Reading Astronomy News
Summary
Exploration: Light as a Wave
5: The Formation of Stars and Planets
5.1: Molecular Clouds Are the Cradles of Star Formation
5.2: The Protostar Becomes a Star
5.3: Planets Form in a Disk around the Protostar
5.4: The Inner and Outer Disk Have Different Compositions
5.5: A Case Study: The Solar System
5.6: Planetary Systems Are Common
Reading Astronomy News
Summary
Exploration: Exploring Exoplanets
6: Terrestrial Worlds in the Inner Solar System
6.1: Impacts Help Shape the Terrestrial Planets
6.2: The Surfaces of Terrestrial Planets Are Affected by Processes in the Interior
6.3: Planetary Surfaces Evolve through Tectonism
6.4: Volcanism Reveals a Geologically Active Planet
6.5: Wind and Water Modify Surfaces
Reading Astronomy News
Summary
Exploration: Earth’s Tides
7: Atmospheres of Venus, Earth, and Mars
7.1: Atmospheres Change over Time
7.2: Secondary Atmospheres Evolve
7.3: Earth’s Atmosphere Has Detailed Structure
7.4: The Atmospheres of Venus and Mars Differ from Earth’s
7.5: Earth’s Climate Is Changing
Reading Astronomy News
Summary
Exploration: Climate Change
8: The Giant Planets
8.1: Giant Planets Are Large, Cold, and Massive
8.2: The Giant Planets Have Clouds and Weather
8.3: The Interiors of the Giant Planets Are Hot and Dense
8.4: The Giant Planets Are Magnetic Powerhouses
8.5: Rings Surround the Giant Planets
Reading Astronomy News
Summary
Exploration: Estimating Rotation Periods of Giant Planets
9: Small Bodies of the Solar System
9.1: Dwarf Planets May Outnumber Planets
9.2: Moons as Small Worlds
9.3: Asteroids Are Pieces of the Past
9.4: Comets Are Clumps of Ice
9.5: Comet and Asteroid Collisions Still Happen Today
9.6: Meteorites Are Remnants of the Early Solar System
Reading Astronomy News
Summary
Exploration: Comparative Dwarf Planetology
10: Measuring the Stars
10.1: The Luminosity of a Star Can Be Found from Its Brightness and Distance
10.2: Radiation Tells Us the Temperature, Size, and Composition of Stars
10.3: The Mass of a Star Can Be Determined in Some Binary Systems
10.4: The Hertzsprung-Russell Diagram Is the Key to Understanding Stars
Reading Astronomy News
Summary
Exploration: The Hertzsprung-Russell Diagram
11: Our Star: The Sun
11.1: The Structure of the Sun Is a Matter of Balance
11.2: Energy in the Sun’s Core Moves through Radiation and Convection
11.3: The Atmosphere of the Sun
11.4: The Atmosphere of the Sun Is Very Active
Reading Astronomy News
Summary
Exploration: The Proton-Proton Chain
12: Evolution of Low-Mass Stars
12.1: The Life of a Main-Sequence Star Follows a Predictable Path
12.2: A Star Runs Out of Hydrogen and Leaves the Main Sequence
12.3: Helium Begins to Burn in the Degenerate Core
12.4: The Low-Mass Star Enters the Last Stages of Its Evolution
12.5: Binary Stars Sometimes Share Mass, Resulting in Novae and Supernovae
12.6: Star Clusters Are Snapshots of Stellar Evolution
Reading Astronomy News
Summary
Exploration: Evolution of Low-Mass Stars
13: Evolution of High-Mass Stars
13.1: High-Mass Stars Follow Their Own Path
13.2: High-Mass Stars Go Out with a Bang
13.3: Supernovae Change the Galaxy
13.4: Einstein Moved beyond Newtonian Physics
13.5: Gravity Is a Distortion of Spacetime
13.6: Black Holes Are a Natural Limit
Reading Astronomy News
Summary
Exploration: The CNO Cycle
14: Measuring Galaxies
14.1: Galaxies Come in Many Sizes and Shapes
14.2: There Are Many Ways to Measure Astronomical Distances
14.3: We Live in an Expanding Universe
14.4: A Supermassive Black Hole Exists at the Heart of Most Galaxies
Reading Astronomy News
Summary
Exploration: Galaxy Classification
15: Dark Matter and the Milky Way
15.1: Galaxies Are Mostly Dark Matter
15.2: Stars Form in the Spiral Arms of a Galaxy’s Disk
15.3: Components of the Milky Way Reveal Its Evolution
15.4: The Milky Way Offers Clues about How Galaxies Form
Reading Astronomy News
Summary
Exploration: Dark Matter in a Galaxy
16: The Evolution of the Universe
16.1: Hubble’s Law Implies a Hot, Dense Beginning
16.2: The Cosmic Microwave Background Confirms the Big Bang
16.3: The Expansion of the Universe Is Speeding Up
16.4: The Earliest Moments of the Universe Connect the Very Largest Size Scales to the Very Smallest
16.5: Inflation Solves Several Problems in Cosmology
16.6: Are There Other Universes?
Reading Astronomy News
Summary
Exploration: Hubble’s Law for Balloons
17: Formation of Structure
17.1: Galaxies Form Groups, Clusters, and Larger Structures
17.2: Gravity Drives the Formation of Large-Scale Structure
17.3: The First Stars and Galaxies Form
17.4: Galaxies Evolve
17.5: Astronomers Think about the Far Future
Reading Astronomy News
Summary
Exploration: The Story of a Proton
18: Life in the Universe
18.1: Life on Earth Began Early and Evolved over Time
18.2: Life beyond Earth Is Possible
18.3: Scientists Search for Signs of Intelligent Life
18.4: The Fate of Life on Earth
Reading Astronomy News
Summary
Exploration: Fermi Problems and the Drake Equation
Appendix 1: Periodic Table of the Elements
Appendix 2: Properties of Planets, Dwarf Planets, and Moons
Appendix 3: Nearest and Brightest Stars
Appendix 4: Star Maps
Glossary
Selected Answers
Credits
Index