Out of the Silent Planet is a science fiction novel by the British author C. S. Lewis, published in 1938 by John Lane, The Bodley Head. Five years later it was published in the U.S. (MacMillan, 1943). Two sequels were published in 1943 and 1945, completing the so-called Cosmic Trilogy or Space Trilogy.

The trilogy was inspired and influenced by David Lindsay's A Voyage to Arcturus (1920).

According to biographer A. N. Wilson, Lewis wrote the novel after a conversation with J.R.R. Tolkien in which both men lamented the state of contemporary fiction. They agreed that Lewis would write a space-travel story, and Tolkien would write a time-travel one. Tolkien's story only exists as a fragment, published in The Lost Road and other writings (1987) edited by his son Christopher. - from Amazon