Water in the Universe

by Arnold Hanslmeier

Overview

Due to its specific chemical and physical properties, water is essential for life on Earth. And it is assumed that this would be the case for extraterrestrial life as well. Therefore it is important to investigate where water can be found in the Universe. Although there are places that are completely dry, places where the last rainfall happened probably several 100 million years ago, surprisingly this substance is quite omnipresent. In the outer solar system the large satellites of Jupiter and Saturn are covered by a thick layer of ice that could be hiding a liquid ocean below. This of course brings up the question of whether the recently detected extrasolar planets could have some water on their surfaces and how we can detect this. Water molecules are also found in interstellar gas and dust clouds. This book begins with an introductory chapter reviewing the physical and chemical properties of water. Then it illuminates the apparent connection between water and life. This is followed by chapters dealing with our current knowledge of water in the solar system, followed by a discussion concerning the potential presence and possible detection of water on exoplanets. The signature of water in interstellar space and stars are reviewed before the origin of water in the Universe is finally discussed. The book ends with an appendix on detection methods, satellite missions and astrophysical concepts touched upon in the main parts of the book. The search for water in the Universe is related to the search for extraterrestrial life and is of fundamental importance for astrophysics, astrobiology and other related topics. This book therefore addresses students and researchers in these fields.

Product Details

ISBN-13:	9789048199839
Publisher:	Springer Netherlands
Publication date:	09/30/2010
Series:	Astrophysics and Space Science Library , #368
Edition description:	2011
Pages:	242
Product dimensions:	6.10(w) x 9.20(h) x 0.80(d)

Table of Contents

1 Water on Earth, Properties of Water 1

1.1 The Role of Water in History 1

1.1.1 Water in Ancient Cultures 1

1.1.2 Modern Society and Water 5

1.2 The Chemical Elements Water Consists of 6

1.2.1 Hydrogen 6

1.2.2 Oxygen 8

1.3 Water, Chemical and Physical Properties 11

1.3.1 Chemical Properties 11

1.3.2 Physical Properties of Water 12

1.3.3 Evaporation and Condensation 16

1.3.4 Ice 17

1.3.5 H₂O+ 19

1.4 Chemical Reactions and Water 20

1.4.1 Chemical Bonds 20

1.4.2 Acids and pH Value 20

1.4.3 Hydrates, Water in Crystals 20

1.4.4 Water: Spectral Signatures 21

1.5 The Hydrologic Cycle 22

1.5.1 Evaporation and Precipitation Balance 22

1.5.2 The Hydrologic Cycle and Climate Change 24

2 Life and Water 25

2.1 Life and Environment 25

2.1.1 The Importance of Water 25

2.1.2 Definition of Life 25

2.1.3 Evolution of Life 27

2.1.4 Life Under Extreme Conditions 30

2.2 Water and Other Solvents 30

2.2.1 The Importance of Solvents to Life 30

2.2.2 Other Solvents than Water 32

2.3 Energy for Life 33

2.3.1 Energy 33

2.3.2 Metabolic Diversity 33

2.3.3 Solar Energy 34

2.3.4 Photosynthesis and Respiration 35

3 Water on Planets and Dwarf Planets 37

3.1 Classification of Objects in the Solar System 37

3.1.1 Overview 37

3.1.2 Physical Parameters of Planets 38

3.2 Terrestrial Planets 38

3.2.1 Earth 39

3.2.2 Mercury 40

3.2.3 Venus 41

3.2.4 Mars 44

3.2.5 The Early Sun and Evolution of Terrestrial Planets 47

3.2.6 Dry Venus-Humid Earth-Climate Changes on Mars 49

3.3 Giant Planets 58

3.3.1 Jupiter 58

3.3.2 Saturn 60

3.3.3 Uranus 61

3.3.4 Neptune 62

3.3.5 Water on Giant Planets 65

3.4 Dwarf Planets 66

3.4.1 Pluto 67

3.4.2 Ices on Other Dwarf Planets 69

4 Satellites of Planets in the Solar System 71

4.1 Galilean Satellites 71

4.1.1 Io 71

4.1.2 Europa 73

4.1.3 Callisto 77

4.1.4 Ganymede 77

4.2 Satellites of Saturn 79

4.2.1 Overview 79

4.2.2 Titan 80

4.2.3 Other Satellites of Saturn 84

4.3 Satellites of Uranus and Neptune 93

4.3.1 The Satellites of Uranus 93

4.3.2 The Satellites of Neptune 97

4.4 The Earth Moon 99

4.4.1 Water on the Moon" 100

5 Water on Small Solar System Bodies 105

5.1 Clouds of Particles 105

5.1.1 The Kuiper Belt 105

5.1.2 The Oort Cloud 110

5.2 Comets 112

5.2.1 Early Observations 112

5.2.2 Orbital Characteristics of Comets 112

5.2.3 Physics of Comets 113

5.2.4 Collisions with Comets 116

5.2.5 Detection of Water on Comets 117

5.3 Asteroids 119

5.3.1 General Properties 119

5.3.2 Classification of Asteroids 119

5.3.3 NEOs 120

5.3.4 The Cretaceous-Tertiary Impact 121

5.3.5 Water and Ice on Asteroids 122

5.3.6 Asteroids as a Source for Water on Earth 124

5.4 Meteorites 124

5.4.1 General Properties 124

5.4.2 Classification 125

5.4.3 Water in Meteorites 126

6 Water on Extrasolar Planets" 129

6.1 How to Detect Extrasolar Planets 129

6.1.1 Detection Methods 129

6.1.2 Extrasolar Planets Found by Different Detection Methods 132

6.1.3 Some Examples of Extrasolar Planets 134

6.2 Habitable Zones 134

6.2.1 Habitability 135

6.2.2 Circumstellar Habitable Zones 135

6.2.3 Galactic Habitable Zone 136

6.2.4 Habitable Zone Around Giant Planets 137

6.3 Dust Debris Around Stars 137

6.3.1 Signatures of Dust Around Stars 138

6.3.2 Dust Around Vega 139

6.4 Water Detection on Extrasolar Planets 141

6.4.1 Detection of Planetary Atmospheres 141

6.4.2 Hot Jupiters 142

6.4.3 Water on Extrasolar Planets 146

6.4.4 Some Model Calculations 146

6.4.5 Super Earth Planets 150

7 Water in Interstellar Space and Stars 153

7.1 Interstellar Medium 153

7.1.1 Physical Properties 153

7.1.2 Molecules in the Interstellar Medium 155

7.1.3 Interstellar Dust Lifecycle 157

7.1.4 Water Masers 158

7.2 Water in Starforming Regions 160

7.2.1 Clouds and Cloud Collapse 160

7.2.2 H₂O Masers in Star Forming Regions-A Model 163

7.2.3 Water Signatures in Protostars 164

7.2.4 T Tauri Stars 166

7.3 Water Signatures in Spectra of Late Type Stars and the Sun 169

7.3.1 Late Type Stars and Water 169

7.3.2 Water in Sunspots" 172

7.4 Water in Galaxies 173

7.4.1 The Milky Way Galaxy 173

7.4.2 Water in the Galaxy" 174

7.4.3 Water in Galaxies 174

7.4.4 Galaxy Clusters 176

7.4.5 IR-Galaxies 176

7.4.6 Water Masers in Nearby Galaxies 178

7.4.7 Mega-Masers 179

8 Water-Where Does It Come from" 181

8.1 The Evolution of the Universe 181

8.1.1 An Expanding Universe 181

8.1.2 Radiation from the Early Universe 182

8.1.3 Abundance of Elements 184

8.1.4 No Water in the Early Universe 185

8.2 Stellar Evolution 185

8.2.1 Red Giants 187

8.2.2 The Asymptotic Giant Branch 189

8.2.3 A Carbon Flash" 189

8.2.4 Post AGB Evolution 190

8.2.5 Elements Heavier than He 190

8.2.6 The Ultimate Fate of a Low Massive Star: White Dwarfs 192

8.3 Massive Stars 192

8.3.1 Main Sequence Evolution of Massive Stars 192

8.3.2 Supernova Explosion 194

8.3.3 Stellar Populations 196

9 Appendix 199

9.1 How to Detect Water 199

9.1.1 Transparency of the Earth's Atmosphere 199

9.1.2 In Situ Measurements 200

9.1.3 Spectroscopic Signatures 201

9.2 Satellite Missions 206

9.2.1 Water Detection with SWAS 206

9.2.2 IR Satellites 207

9.2.3 Future Astronomical Telescopes 208

9.3 Some Astrophysical Concepts 209

9.3.1 Apparent Magnitude 209

9.3.2 Spectral Classes 210

9.3.3 The Hertzsprung-Russell Diagram, HRD 211

References 213

Index 231