The frontier falls away
Pluto is still close enough to fill the cockpit view when departure is confirmed. A countdown breaks the stillness; then blue-white fire lifts the ship from the frozen bay. For a few moments, the frontier remains beneath it—solid, visible, almost within reach.
As altitude becomes distance, the meaning of the launch changes. This is no longer only a machine escaping gravity. The last human threshold is receding, and the expedition is entering the dark before it knows what waits there.
The known world does not disappear at once. It falls away slowly enough for the departure to be watched.
When does a liftoff cease to be ascent and become departure?