Kelis' homeworld was a class L planet located in the Delta Quadrant and home to Kelis' species, a pre-warp civilization. The fourth planet orbiting an F-type star, it was only accessible by an area of space that was affected by spatial eddies causing affected ships to lose power.
Certain parts of the planet contained a great quantity of rocky, forested hillside and valley landscapes including areas with some sort of hunting game. The planet also contained several land masses and at least one body of water called the Eastern Sea. It had natural dilithium deposits on nearly every landmass, which the native species referred to as winter's tears. The planet also contained at least some deposits of copper, gold, and tin. The planet was capable of producing rain and at times even quite strong thunder and lightning storms. Kelis stated that wars were fought whenever the local warlords or autarchs were ensured of good weather.
In 2376, the Delta Flyer piloted by B'Elanna Torres and Harry Kim was forced to crash land on the planet while searching for dilithium. Lieutenant Commander Tuvok expressed concern that the USS Voyager might also fall victim to the eddies that had caused the disappearance of the Delta Flyer. After Ensign Kim, whose escape pod landed at a different location, finally reached Lt. Torres and the Flyer after walking two hundred kilometers with the part she needed to contact Voyager, both were evacuated. (VOY: "Muse")
Kelis' homeworld appeared somewhat atypical of a class L planet, which are otherwise described as "barely habitable", often with atmospheres unsuitable to humanoid life. Although Kim and Torres were not shown to use any visible life-sustaining equipment, little was seen of the planet's surface and the remainder of the planet might have been far less hospitable and more standard for a class L planet.
According to Star Trek: Star Charts (p. 93), Kelis' homeworld was located in the FGC-538960 system. The USS Voyager visited this system on stardate 53896.