Astronomy For Dummies

Introduction 1 About This Book 2 Foolish Assumptions 2 Icons Used in This Book 3 Beyond the Book 3 Where to Go from Here 4 Part 1: Getting Started with Astronomy 5 Chapter 1: Seeing the Light: The Art and Science of Astronomy 7 Astronomy: The Science of Observation 8 What You See: The Language of Light 9 They wondered as they wandered: Understanding planets versus stars 10 If you see a Great Bear, start worrying: Naming stars and constellations 10 What do I spy? Spotting the Messier Catalog and other sky objects 18 The smaller, the brighter: Getting to the root of magnitudes 19 Looking back on light-years 19 Keep on moving: Figuring the positions of the stars 22 Gravity: A Force to Be Reckoned With 25 Space: A Commotion of Motion 26 Chapter 2: Join the Crowd: Skywatching Activities and Resources 29 You're Not Alone: Astronomy Clubs, Websites, Smartphone Apps, and More 30 Joining an astronomy club for star-studded company 30 Checking websites, magazines, software, and apps 31 Visiting Observatories and Planetariums 34 Ogling the observatories 35 Popping in on planetariums 38 Vacationing with the Stars: Star Parties, Eclipse Trips, Dark Sky Parks, and More 38 Party on! Attending star parties 39 Getting festive at an AstroFest 40 Tapping into Astronomy on Tap 40 To the path of totality: Taking eclipse cruises and tours 40 Motoring to telescope motels 42 Setting up camp at dark sky parks 44 Chapter 3: Terrific Tools for Observing the Skies 47 Seeing Stars: A Sky Geography Primer 48 As Earth turns 48 keep an eye on the North Star 50 Beginning with Naked-Eye Observation 52 Using Binoculars or a Telescope for a Better View 55 Binoculars: Sweeping the night sky 56 Telescopes: When closeness counts 60 Planning Your First Steps into Astronomy 66 Chapter 4: Just Passing Through: Meteors, Comets, and Artificial Satellites 69 Meteors: Wishing on a Shooting Star 70 Spotting sporadic meteors, fireballs, and bolides 72 Watching a radiant sight: Meteor showers 74 Comets: The Lowdown on Dirty Ice Balls 79 Making heads and tails of a comet's structure 80 Waiting for the comets of the century 84 Hunting for the great comet 86 Artificial Satellites: Enduring a Love-Hate Relationship 88 Skywatching for artificial satellites 89 Finding satellite viewing predictions 91 Part 2: Going Once Around the Solar System 93 Chapter 5: A Matched Pair: Earth and Its Moon 95 Putting Earth under the Astronomical Microscope 96 One of a kind: Earth's unique characteristics 96 Spheres of influence: Earth's distinct regions 99 Examining Earth's Time, Seasons, and Age 101 Orbiting for all time 102 Tilting toward the seasons 103 Estimating Earth's age 105 Making Sense of the Moon 106 Get ready to howl: Identifying phases of the Moon 107 In the shadows: Watching lunar eclipses 110 Cultivating an interest in the occult(ations) 111 Hard rock: Surveying lunar geology 112 Quite an impact: Considering a theory about the Moon's origin 117 Chapter 6: Earth's Near Neighbors: Mercury, Venus, and Mars 119 Mercury: Weird, Hot, and Mostly Metal 120 Dry, Acidic, and Hilly: Steering Clear of Venus 121 Red, Cold, and Barren: Uncovering the Mysteries of Mars 123 Where has all the water gone? 124 Does Mars support life? 126 Differentiating Earth through Comparative Planetology 128 Observing the Terrestrial Planets with Ease 129 Understanding elongation, opposition, and conjunction 130 Viewing Venus and its phases 132 Watching Mars as it loops around 134 Outdoing Copernicus by observing Mercury 138 Chapter 7: Rock On: The Asteroid Belt and Near-Earth Objects 141 Taking a Brief Tour of the Asteroid Belt 141 Understanding the Threat That Near-Earth Objects Pose 145 When push comes to shove: Nudging an asteroid 147 Forewarned is forearmed: Surveying NEOs to protect Earth 148 Searching for Small Points of Light 149 Helping to track an occultation 150 Timing an asteroidal occultation 151 Chapter 8: Great Balls of Gas: Jupiter and Saturn 153 The Pressure's On: Journeying Inside Jupiter and Saturn 153 Almost a Star: Gazing at Jupiter 154 Scanning for the Great Red Spot 156 Shooting for Galileo's moons 157 Our Main Planetary Attraction: Setting Your Sights on Saturn 161 Ringing around the planet 161 Storm chasing across Saturn 162 Monitoring a moon of major proportions 163 Venting about geysers on Enceladus 165 Chapter 9: Far Out! Uranus, Neptune, Pluto, and Beyond 167 Breaking the Ice with Uranus and Neptune 167 Bull's-eye! Tilted Uranus and its features 168 Against the grain: Neptune and its biggest moon 169 Meeting Pluto, the Amazing Dwarf Planet 170 Getting to the heart of Pluto 171 Looking at Pluto's makeup 173 The moon chip doesn't float far from the planet 174 Buckling Down to the Kuiper Belt 175 Viewing the Outer Planets 176 Sighting Uranus 176 Distinguishing Neptune from a star 177 Straining to see Pluto 178 Hunting New Planet Number Nine 178 Part 3: Meeting Old Sol and Other Stars 181 Chapter 10: The Sun: Star of Earth 183 Surveying the Sunscape 184 The Sun's size and shape: A great bundle of gas 185 The Sun's regions: Caught between the core and the corona 185 Solar activity: What's going on out there? 187 Solar wind: Playing with magnets 191 Solar CSI: The mystery of the missing solar neutrinos 192 Four billion and counting: The life expectancy of the Sun 193 Don't Make a Blinding Mistake: Safe Techniques for Solar Viewing 194 Viewing the Sun by projection 194 Viewing the Sun through front-end filters 198 Fun with the Sun: Solar Observation 200 Tracking sunspots 200 Experiencing solar eclipses 202 Looking at solar pictures on the Net 206 Chapter 11: Taking a Trip to the Stars 209 Life Cycles of the Hot and Massive 210 Young stellar objects: Taking baby steps 211 Main sequence stars: Enjoying a long adulthood 212 Red giants: Burning out the golden years 213 Closing time: Coming up on the tail end of stellar evolution 213 Star Color, Brightness, and Mass 219 Spectral types: What color is my star? 220 Star light, star bright: Luminosity classifications 221 The brighter they burn, the bigger they swell: Mass determines class 222 The H-R diagram 223 Eternal Partners: Binary and Multiple Stars 225 Binary stars and the Doppler effect 225 Two stars are binary, but three's a crowd: Multiple stars 228 Change Is Good: Variable Stars 230 Go the distance: Pulsating stars 231 Explosive neighbors: Flare stars 232 Nice to nova: Exploding stars 233 Stellar hide-and-seek: Eclipsing binary stars 235 Hog the starlight: Microlensing events 236 Your Stellar Neighbors 237 How to Help Scientists by Observing the Stars 239 Star Studies to Aid with Your Brain and Computer 240 Chapter 12: Galaxies: The Milky Way and Beyond 241 Unwrapping the Milky Way 241 How and when did the Milky Way form? 243 What shape is the Milky Way? 243 Where can you find the Milky Way? 245 Star Clusters: Meeting Galactic Associates 246 A loose fit: Open clusters 246 A tight squeeze: Globular clusters 248 Fun while it lasted: OB associations 250 Taking a Shine to Nebulae 250 Picking out planetary nebulae 252 Breezing through supernova remnants 253 Enjoying Earth's best nebular views 254 Getting a Grip on Galaxies 256 Surveying spiral, barred spiral, and lenticular galaxies 257 Examining elliptical galaxies 258 Looking at irregular, dwarf, and low surface brightness galaxies 259 Gawking at great galaxies 260 Discovering the Local Group of Galaxies 263 Checking out clusters of galaxies 263 Sizing up superclusters, cosmic voids, and Great Walls 264 Joining Galaxy Zoo for Fun and Science 265 Chapter 13: Digging into Black Holes and Quasars 267 Black Holes: Keeping Your Distance 267 Looking over the black hole roster 268 Poking around the black hole interior 269 Surveying a black hole's surroundings 271 Warping space and time 272 Detecting black hole collisions 274 Watching stars get swallowed by black holes 275 Quasars: Defying Definitions 276 Measuring the size of a quasar 277 Getting up to speed on jets 277 Exploring quasar spectra 278 Active Galactic Nuclei: Welcome to the Quasar Family 278 Sifting through different types of AGN 278 Examining the power behind AGN 280 Proposing the Unified Model of AGN 281 Part 4: Pondering the Remarkable Universe 283 Chapter 14: Is Anybody Out There? SETI and Planets of Other Suns 285 Using Drake's Equation to Discuss SETI 286 SETI Projects: Listening for E T 289 The flight of Project Phoenix 290 Space scanning with other SETI projects 291 Hot targets for SETI 292 SETI wants you! 293 Discovering Alien Worlds 293 Changing ideas on exoplanets 294 Finding exoplanets 295 Meeting the (exo)planets 298 Catching Proxima fever: Focusing on red dwarfs 300 Finding Earth-class planets orbiting TRAPPIST-1 302 Checking out planets for fun and science 303 Astrobiology: How's Life on Other Worlds? 304 Extremophiles: Living the hard way 304 Seeking life in the solar system 305 Chapter 15: Delving into Dark Matter and Antimatter 309 Dark Matter: Understanding the Universal Glue 309 Gathering the evidence for dark matter 310 Debating the makeup of dark matter 314 Taking a Shot in the Dark: Searching for Dark Matter 315 Looking for WIMPs and other microscopic dark matter 316 MACHOs: Making a brighter image 317 Mapping dark matter with gravitational lensing 318 Dueling Antimatter: Proving That Opposites Attract 319 Chapter 16: The Big Bang and the Evolution of the Universe 321 Evidence for the Big Bang 322 Inflation: A Swell Time in the Universe 324 Something from nothing: Inflation and the vacuum 325 Falling flat: Inflation and the shape of the universe 325 Dark Energy: The Universal Accelerator 326 Universal Info Pulled from the Cosmic Microwave Background 327 Finding the lumps in the cosmic microwave background 328 Mapping the universe with the cosmic microwave background 328 In a Galaxy Far Away: Standard Candles and the Hubble Constant 330 Standard candles: How do scientists measure galaxy distances? 330 The Hubble constant: How fast do galaxies really move? 331 The Fate of the Universe 332 Part 5: The Part of Tens 333 Chapter 17: Ten Strange Facts about Astronomy and Space 335 You Have Tiny Meteorites in Your Hair 335 A Comet's Tail Often Leads the Way 336 Earth Is Made of Rare and Unusual Matter 336 High Tide Comes on Both Sides of Earth at the Same Time 336 On Venus, the Rain Never Falls on the Plain 336 Rocks from Mars Dot Earth 337 Pluto Was Discovered from the Predictions of a False Theory 337 Sunspots Aren't Dark 337 A Star in Plain View May Have Exploded, but No One Knows 338 You May Have Seen the Big Bang on an Old Television 338 Chapter 18: Ten Common Errors about Astronomy and Space 339 The Light from That Star Took 1,000 Light-Years to Reach Earth 339 A Freshly Fallen Meteorite Is Still Hot 340 Summer Always Comes When Earth Is Closest to the Sun 340 The Back of the Moon Is Dark 340 The Morning Star Is a Star 340 If You Vacation in the Asteroid Belt, You'll See Asteroids All Around You 341 Nuking a Killer Asteroid on a Collision Course for Earth Will Save Us 341 The Sun Is an Average Star 342 The Hubble Telescope Gets Up Close and Personal 342 The Big Bang Is Dead 342 Part 6: Appendixes 343 Appendix A: Star Maps 345 Appendix B: Glossary 353 Sky Measures 356 Index 357