- Technology Marches On:
- In the distant interstellar future, tape is the most common sound recording medium.
- In "Ribbon in the Sky" there is a mention of spaceship navigation computers being programmed using punched cards.
- Also in "Ribbon in the Sky", following an error in the navigation computer, Calhoun is faced with the task of determining his location by matching the stars around him with those in the records. This involves taking a physical photograph of the display on the ship's viewscreen, developing the photograph, and manually comparing it with a set of similar photographs stored on microfilm.
Trivia / Med Ship