What is Mars? From the ancients to the present, we have imagined Mars repeatedly and studied it longingly.As scientific knowledge of Mars has changed, so has the cultural imagination of this celestial neighbors.The earth-centered beginnings of astronomy connected the blood-red planet with the God of War.The Copernican Revolution and a later, simple mistranslation from Italian supported fantastic visions of distant Mars as the abode of life variously bizarre, ideal, or malignant.In the work of H. G. Wells and Orson Welles, in books, films, radio, and television, Mars reflected not only eternal hopes and fears but then-current political realities.In recent years, NASA-fication has brought Mars home, imagining the Red Planet almost as an eighth continent of Earth, a candidate for exploration and exploitation both in fiction and in fact.Rabkin weaves a chronological tale of many threads, including mythology, astrology, astronomy, literary criticism, and cultural studies.