Callisto was discovered by astronomer Galileo Galilei in 1610. The likely presence of water, low levels of radiation and geological stability of this moon has caused scientific interest. It is often viewed as a likely location for human colonization, provided space travel technology improves within the 21st century. 
 
Callisto features frequently in science fiction settings. Howard Phillips Lovecraft (1890-1937), Robert Anson Heinlein (1907-1988), Isaac Asimov (1920-1992), Philip Kindred Dick (1928-1982),  and Lin Carter (1930-1988) are among the writers who have featured a habitable Callisto as part of their stories.