in the decades following mariner and apollo, the once-popular subgenre of realistic stories about a first expedition to mars fell out of fashion, possibly due to the failure of the apollo program to continue on to mars. the early 1990s saw a revival and re-envisioning of realistic novels about mars expeditions. early novels in this renaissance were jack williamson's novel "beachhead" and ben bova's novel "mars" (both 1992), which envisioned large-scale expeditions to mars according to the thinking of the 1990s. these were followed by gregory benford's "the martian race" (1999), geoffrey a. landis's "mars crossing" (2000), and robert zubrin's "first landing" (2002), which took as their starting points the smaller and more focussed expedition strategies evolved in the late 1990s, mostly building on the concepts of mars direct.