"Encounter in the Dawn" (also known as "Expedition to Earth") is a short story by English writer Arthur C. Clarke, first published in 1953 in the magazine Amazing Stories. It was originally collected in the anthology Expedition to Earth, and, in one edition of the book, is titled "Expedition to Earth". In a later collection the title "Encounter at Dawn" is used. The story was later restyled and used as the basis for the first section of Clarke's 1968 novel 2001 A Space Odyssey. In Clarke's 1972 book The Lost Worlds of 2001, the author noted: