Short Story
Barrier to Yesterday
- by Bob Shaw
- in Nebula Science Fiction #16, March 1956
The story revolves around tribes who migrate to follow the sun around a slowly rotating world. I don’t understand what the title refers to, but it is not time travel. —Michael Main
He seemed to think it was a privilege to live on a world whose spin had almost stopped, stretching the days and nights into years so that it was useless even to go underground.