On a Sunbeam is a science fiction webcomic, later released as a graphic novel, by American cartoonist Tillie Walden. Set in a spacefaring science fiction world, the plot follows the development of the protagonist Mia, who joins the crew of the maintenance ship Aktis and attempts to reconnect with a lost love. It was nominated for the 2017 Eisner Award for Best Digital Comic and the graphic novel won the 2018 Los Angeles Times Book Prize.