Ratner's Star is a 1976 novel by Don DeLillo. It relates the story of a child prodigy mathematician who arrives at a secret installation to work on the problem of deciphering a mysterious message that appears to come from outer space. The novel has been described as "famously impenetrable".^[1]

The novel is described as Menippean satire and akin to the works of Thomas Pynchon.^[2] In critical reviews, the protagonist, Billy Twillig, is compared to Vonnegut's Billy Pilgrim.^[3]

The novel is told in two parts; the first is a conventional narrative, the second is less so. The author has said that the structural model was Alice's Adventures in Wonderland and Through the Looking-Glass.^[4] The novel develops the idea that science, mathematics, and logic—in parting from mysticism—do not contain the fear of death, and therefore offer no respite.