The space traveler Elwin in C.S. Lewis’s Space Trilogy is Elwin Ransom.
Ransom is the central human character in Out of the Silent Planet, Perelandra, and That Hideous Strength. He begins the series as a philologist who is abducted and taken to Malacandra, the planet commonly identified with Mars. His knowledge of languages becomes crucial as he encounters unfamiliar peoples and cultures.
The surname is sometimes confused with other important characters in the trilogy. Edward Weston is a scientist and antagonist in the first two books, while Mark Studdock is a major character in That Hideous Strength. Ransom, however, is the recurring protagonist whose experiences link the trilogy together.
Lewis published the three novels between 1938 and 1945. They combine planetary adventure with Christian theology, moral philosophy, language, and speculation about humanity’s place in the universe. The books are often called the Cosmic Trilogy as well as the Space Trilogy.