This foundational work on astronomy by Robert S. Ball opens with a detailed examination of the astronomical observatory, detailing the evolution of optical instruments from Tycho Brahe's primitive tools to the great reflecting telescopes of Lord Rosse and the precise measurements of the meridian circle. The author explains how modern astrophotography and spectroscopy have revolutionized our understanding of the cosmos by allowing scientists to analyze starlight and determine the chemical composition of celestial bodies. Moving beyond instrumentation, Ball turns to our peerless sun, examining its immense dimensions, its granulated photosphere, the periodicity of sunspots, and their mysterious connection to terrestrial magnetism.
The reader is guided through the brilliant phenomena of prominences and the corona revealed during total eclipses, as well as the profound physical principles of spectrum analysis that identify terrestrial elements within the solar atmosphere. The narrative then shifts to the moon, exploring its profound influence on ocean tides, the mechanics of lunar and solar eclipses, and the rugged, waterless topography of lunar craters like Plato and Tycho. Ball evaluates the theories of volcanic and impact origins for these structures, and discusses the complete absence of air and water, rendering organic life as we know it impossible on our satellite.
Expanding the horizon, the author introduces the solar system as an isolated island group in space, examining the orbits, distances, and relative sizes of the planets from Mercury to Neptune. The final sections elucidate the universal law of gravitation, demonstrating how Newton's genius united Kepler's empirical laws of planetary motion into a single majestic doctrine. Through clear illustrations and rigorous reasoning, Ball explains how celestial bodies move in elliptic paths under the control of central attraction, providing a comprehensive foundation for the study of the heavens.
