The Paradox of Patience
The dream of interstellar travel collides with an unsettling idea: maybe we shouldn’t go—yet. Physicist and writer Robert L. Forward argued that launching a mission that takes longer than about 50 years is wasteful, because progress in propulsion might produce a faster ship later that races past the pioneer.
This is the “incessant obsolescence” problem. If technology keeps improving, every starship risks being overtaken by a better one launched afterward.
Timing the Jump to the Stars
In 2006, Andrew Kennedy took this idea further, devising a more precise wait calculation. He asked: if propulsion performance grows at a steady rate, when is the ideal moment to launch so that your ship arrives sooner than any that could depart later?
Looking at a destination about six light-years away, Kennedy found that if propulsion tech improves by around 1.4% per year, the optimal launch date falls roughly 635 years in the future, around the year 2641. Launch earlier, and you risk being overtaken; launch later, and you miss your moment.
Competing Futures
This simple calculation has profound implications. For competing cultures aiming to settle or explore the same star systems, timing becomes a strategic decision. A civilization that understands and optimizes its wait calculation might dominate the galactic expansion game, while impatient rivals waste colossal resources on missions doomed to be second.
Takeaway
Interstellar travel isn’t just about building engines—it’s about choosing when to light them. In a universe governed by both physics and progress, patience can be its own kind of propulsion.