How long can the main-sequence lifespan of a K-type orange dwarf potentially extend beyond that of the Sun?
K-type stars can live for tens of billions of years, potentially trillions.
The primary advantage cited for K-type stars is their significantly extended longevity compared to a G-type star like the Sun, which lasts about ten billion years on the main sequence. Because K-stars are less massive, they burn their fuel much more slowly, a process described as sipping fuel over eons. This translates directly into potential main-sequence lifespans reaching fifteen, fifty, or even trillions of years, depending on the subtype. This massive evolutionary buffer provides an enormous stretch of stable time, allowing vastly greater opportunities for biological complexity to arise and evolve without the immediate threat of stellar evolution ending the support window.
