Chapter 9

_HOW TO FIND THE PLANETS_ 256

It is easy to make acquaintance with the planets and to follow them among the stars--The first step a knowledge of the constellations--How this is to be acquired--How to use the Nautical Almanac in connection with the charts in this book--The visibility of Mercury and Venus--The oppositions of Mars, Jupiter, and Saturn

INDEX 277

LIST OF ILLUSTRATIONS

PAGE Chart of Mars _Frontispiece_

Diagram showing causes of day and night on portions of Mercury 35

Regions of day and night on Mercury 38

Venus's atmosphere seen as a ring of light 56

View of Jupiter _facing_ 168

Three views of Saturn _facing_ 186

Diagram showing the moon's path through space 217

The lunar Alps, Apennines, and Caucasus _facing_ 222

The moon at first and last quarter _facing_ 226

Phases and rotation of the moon 250

Charts showing the zodiacal constellations: 1. From right ascension 0 hours to 4 hours 259 2. " " 4 " " 8 " 261 3. " " 8 " " 2 " 263 4. " " 12 " " 16 " 265 5. " " 16 " " 20 " 267 6. " " 20 " " 24 " 269

OTHER WORLDS