The binary world of Kennesawu is home to two sentient life forms: the Guigu and the Symtraya. Both Kennu (the larger world) and Sawu (the smaller one) are tidally locked to each other, with the same hemisphere of each one facing the other permanently. The Symtraya, a naturally spacefaring species, occupy the prime launch sites-points on either side of the binary system's main axis, at the equator. The Guigu—a small primate species, well-adapted to both warm and chilly climates—have become the dominant civilization on the planet, filling most of the rest of the land area.
Kennesawu has a 38º axial tilt, long days (44 hours), and a long year (twice as long as Earth's year). On Kennu, this results in wide temperature extremes between seasons, but the planetary average temperature is always just below freezing. In the northern hemisphere's summer, the average temperature is 20ºC (during this time, the `TMP` value is 3). In winter, the average temperature is -25ºC. During the dead of both the summer and winter, the equator is below freezing, but it remains above freezing most other times.
Most of the water on Kennu is locked up in snow for most of the year. Underground hot springs are plentiful, and the Guigu take advantage of these when they retreat into their burrows for the winter. When the summer comes, the snow thaws, the hot springs turn into river sources, and the frozen forest comes to life.
Finally, Kennu has an extraordinarily strong magnetic field, which is what allows the Symtraya's natural spacefaring capabilities. Many species of life migrate from the north to the south to follow the warm seasons, and many of those take advantage of the magnetic field to make this flight easier.