800,000 light years away there is a heavenly body called the Hydra cluster; far beyond it spin still un-named islands of matter. Man is probing into this inconceivable vastness. He is already on the first lap of the journey to new worlds, new existences. How did this remarkable scientific renaissance occur in such a minute portion of human time? In this gripping and vivid study, Lloyd Motz, a leading American astronomer, tells just what present-day scientific thought has to say about the universe. he shows how Einstein's theory of the fourth dimension opposed the classic Euclidean concept, revolutionizing our ideas of matter, energy, time, and space. Here are the fascinating theories of cosmic history, including the most recent achievements of the men who are providing a breakthrough to the stars. This Is Outer Space is one of the books in the Signet Science Library, works by leading scientists and educators that present nontechnical explanations of the latest knowledge, developments, and discoveries in the field of science.