This exemplary entry from the Encyclopedia of Science Fiction provides an erudite overview of the dozens of important works that have taken up Mars as a theme or setting. Here readers will learn how writings about Mars adapted and changed as the scientific understanding of the Red Planet grew. For instance, in the late 19th century Mars was often envisioned as a setting for utopian extraterrestrial societies that were used to critique social structures of class, exploitation, racism, and suppression of women in Europe and the United States. In contrast, by the mid-20th century, many authors imagined Mars as a place to which humans with a greater vision might escape to create their own utopian societies. There were also "planetary romance" stories throughout the 20th century that focused on relationships between humans and various kinds of Martians. More recently, of course, fiction based on Mars has taken a turn toward realism, as exemplified by Andy Wier's The Martian.