Magazine in 1981 but now available in King's short story collection
The Skeleton Key, "The Jaunt" tells the story of a future where teleportation technology has been developed, which the story derives its name from, as humankind starts "jaunt-ing" around the solar system, slowly colonising other planets. The story itself revolves around a man named Mark Oates, who's preparing his children for their trip from Schenectady, New York to Mars, by telling them about the history of how this form of travel even came to be — and how it can only be done while a person is unconscious as the process either kills people or drives them insane.