Trivia / Tau Zero

• Science Marches On:
  • The Bussard engine which is used in this novel (and many others during the time period) doesn't really work as advertised. In short, the enormous drag of collecting interstellar hydrogen limits the ramjet's speed to about 12% light-speed.
  • One of the scenes in the book has the ship coasting in blackness (they're essentially moving too fast to see the light from the stars) while the crew goes outside to make repairs. Missing from the scene is the cosmic microwave background, discovered at around the time the original short story was written. At the speed the ship was going, it would be blueshifted far enough into the gamma spectrum to kill people instantly from radiation poisoning.
  • The recent discovery of Dark Energy pretty much seals the coffin on having a "big crunch" at the end of the universe, like the Big Crunch described in the novel.