The Earth… But Not As We Know It – An Exploration

All human beings, by nature, desire to know." —Aristotle, The Metaphysics. For well over 2,000 years, much of our fundamental "desire to know" has focused on the area we now call science. In fact, our commitment to science and technology has been so profound that these now stand as probably the most powerful of all influences on human culture.

Every single day of your life is spent within a civilization—an elaborate system composed of governing bodies, detailed laws, dense urban centers, elaborate trade networks, visual and written cultures, class structures, militaries, and more.

Energy, chemistry, solvents, and habitats – the basic elements of living systems - define the opportunities and limitations for life on other worlds. This class-tested text examines each of these parameters in crucial depth and makes the argument that life forms we would recognize may be more common in our solar system than many assume. It also considers, however, exotic forms of life that would not have to rely on carbon as basic chemical element, solar energy as a main energy source, or water as primary solvent. Finally the question of detecting bio- and geosignature of such life forms is discussed, ranging from Earth environments to deep space.