The paper describes an upper-division university course in Mars literature taught online since Fall 2013. The course readings comprise six novels relating to Mars. Authors include H.G. Wells, Edgar Rice Burroughs, Ray Bradbury, Phillip K. Dick, Greg Bear, and Kim Stanley Robinson. After an introduction, sections of the paper discuss course organization and syllabus, Americanist conceptual approaches, anti-colonialism, habitat sustainability, and pedagogical possibilities for future discussion of Mars literature. The paper argues for a fiction-based approach to understanding historical and potential future relationships with Mars and Mars science.