pluto

Orbiting at the edge of the outer Solar System, Pluto is anintriguing object in astronomy. Since the fascinating eventssurrounding its discovery, it has helped increase our understandingof the origin and evolution of the Solar System, and raisedquestions about the nature and benefits of scientificclassification. This is a timely and exciting account of Pluto andits satellites. The author uses Pluto as a case study to discussdiscovery in astronomy, how remote astronomical bodies areinvestigated, and the role of classification in science bydiscussing Pluto's recent classification as a dwarf planet. BesidesPluto, the book also explores the rich assortment of bodies thatconstitute the Edgeworth–Kuiper Belt, of which Pluto is the largestinnermost member. Richly illustrated, this text is written forgeneral readers, amateur astronomers and students alike. Boxed textprovides more advanced information especially for readers who wishto delve deeper into the subject.

Shows how studies of Pluto have increased our knowledge inimportant areas in planetary science, including the origin andevolution of the Solar System · Uses Pluto as a case study toillustrate how remote astronomical bodies are investigated, and therole of classification in science · Explores the entireEdgeworth–Kuiper Belt, of which Pluto is the innermost member. ^[1] 

List of tables ix

Preface x

Acknowledgements xii

1　The Solar System 1

1.1　A journey into our Galaxy 1

1.2　The Solar System: sizes and orbits 3

1.3　Planetary compositions 14

1.4　The Sun 23

1.5　The origin of the Solar System 27

1.6　Making measurements of distances, sizes and masses 32

2　The discovery of Uranus, Neptune and Pluto 37

2.1　The discovery of Uranus 37

2.2　The discovery of Neptune 42

2.3　The discovery of Pluto 56

2.4　Pluto surprises 68

2.5　Why no collisions with Neptune? 71

3　Pluto: a diminishing world 74

3.1　Pluto's size 74

3.2　Pluto's mass 82

3.3　Pluto's density and global composition 87

4　Pluto's family 93

4.1　Revolutions and rotations 93

4.2　Masses, sizes, densities and global compositions 101

4.3　The origin of Pluto and its satellites 105

5　Surfaces, atmospheres and interiors of Pluto and Charon 112

5.1　Reflection and emission spectra 112

5.2　Surfaces 117

5.3　Atmospheres 128

5.4　Interiors 139

6　The Edgeworth-Kuiper belt 146

6.1　Why search for more trans-Neptunian objects? 146

6.2　The trickle and the flood 149

6.3　Kuiper belt objects 152

6.4　The origin and evolution of the E-K belt 162

6.5　Centaurs and short-period comets 166

7　Is Pluto a planet? 169

7.1　The role of classification in science 169

7.2　Planets before Pluto's discovery: antiquity to 1930 171

7.3　The classification of Pluto 174

8　The New Horizons mission to Pluto (and beyond) 183

8.1　The long path to New Horizons 183

8.2　Mission objectives 187

8.3　The spacecraft: instrumentation and journey 190

9　Pluto: gateway to beyond? 195

9.1　To stand on Pluto 195

9.2　Pluto: a launch platform? 203

Glossary 207

Further reading and other resources 213

Index 226 ^[1]