Prologue Scale of the Universe

Figure P.1a The Constellation Orion

Figure P.1b The Constellation Orion

Figure P.2 The Celestial Sphere

Figure P.3 The Northern Sky

Figure P.4 Right Ascension and Declination

Figure P.5 Solar and Sidereal Days

Figure P.6 The Zodiac

Figure P.7 Ecliptic

Figure P.8 Seasons

Figure P.9 Precession

More Precisely P-1 Angular Measure

Figure P.10 Triangulation

Figure P.11 Parallax

Figure P.12 Parallax Geometry

More Precisely P-2a Measuring Distances with Geometry

More Precisely P-2b Measuring Distances with Geometry

Discovery P-1 Sizing Up Planet Earth