2 books -- The Cosmological Distance Ladder: Distance and Time in the Universe + Theories of the Universe

The scale of cosmological distances has been a topic of dramatic controversy during the past decade. Experts estimating the size of the universe, as measured by the Hubble constant, have differed by as much as a factor of two. Just how big is the universe, and why have distance measurements varied to greatly? Michael Rowan-Robinson sheds new light on the origins of this controversy, critically reviewing the main techniques of measuring distances between astronomical bodies both within and outside our galaxy. Stars, galaxies, and cluster of galaxies all play a major part in the distance ladder, and knowledge of distance is essential for all branches of astronomy. As we examine the geometrical speculations of the Greeks and the first correct estimates of the relative distances of the planets from the Sun by Copernicus we realize that this is also a history of mankind's expanding horizon. Offering a fair, balanced review and a clear synthesis of the variety of techniques and methods for measuring cosmological distances (including the work of Gerard del Vaucouleurs, Allan Sandage, Gustav Tammann, and others), Rowan-Robinson integrates the various distance-measuring methods and presents a new, revised distance scale for the known universe. He supplies a unique perspective on modern astronomy itself as he pursues and expanding scale of distance from the solar system outward. Extensively illustrated with photographs and line drawings.