It's not the size that matters...
Purrfang is the homeword of the K'Nes species and capital of the K'Nes Llan. Purrfang is not actually a planet, but the largest moon obiting a superjovian gas giant, the third planet in that solar system. The capital city is Awuon, and their Impball team is the Purrfang Cats.
Astronomical Data[]
Aphelion: 1.24 AU
Perihelion: 0.89 AU
Axial Tilt: 0.01°
Orbital Period: 10.85 Earth years
Rotational Period: 7.2 Earth days
Influence on K'Nes Evolution[]
Purrfang orbits its gas giant planet once every 172.8 hours – so one Purrfang "day" is equal to 7.2 Earth days. As the moon has almost no axial tilt, Purrfang's days and nights last roughly equal lengths of time – 86.4 hours (3.6 Earth days) each of daylight and nighttime. The K'Nes sleep cycle has evolved to match the Purrfangian day. During their active phase, K'Nes have incredible stamina and can stay awake and active much, much longer than humans. Their extended nocturnal phase, however, has earned them a reputation among humans for "sleeping all the time."
Purrfang's planet orbits the system's sun once every 550 Purrfang days (95,040 hours). One Purrfang "year" is equal to 10.85 Earth years. The K'Nes calendar is broken up into 11 months of 50 days each (or 360 Earth days, just under one Earth year per Purrfang month).
The orbit of the gas giant and its moon Purrfang takes it to the inner and outer edges of the habitable zone around their sun. At the height of the Purrfang winter, at its farthest point from the sun, the polar ice caps expand, the temperate zones freeze, the sea level drops, and water only remains in a liquid state near the equator. At the height of the Purrfang summer, at its closest point to the sun, the polar caps almost disappear, the sea level rises, the equatorial and temperate zones become hot, humid swamps, and plant life booms. One theory of K'Nes evolution proposes that K'Nes developed the ability to float in order to cross terrain alternately frozen or flooded with equal ease.
The K'Nes reproductive life cycle has evolved to match this long, long orbit around the sun. To take advantage of the long, bountiful Purrfang summers when food sources are plentiful, K'Nes young are conceived, born, and mature to adolescence during the summers, a period of about 3.6 Earth years. As K'Nes only reproduce once every eleven years, they conceive several offspring simultaneous, birthing litters of between three and twelve cubs. Compared to humans and Jurvain, K'Nes have a very low birth rate, resulting in comparatively small populations and very slow population growth. This is one of the many reasons why K'Nes have generally preferred economic expansion over military expansion for much of their history.
The moon Purrfang is tidally locked in geosynchronous orbit around its gas giant, meaning one side of the moon always faces toward the planet, and one side always faces away from it. During the day, however, the "dark side" of Purrfang is still illuminated by light reflected off the planet (which is so big it can seem to fill the whole sky). Still, even in summer, the dark side of Purrfang is colder than the bright side, leading to the evolution of long-haired and short-haired K'Nes.