Delta Canaris IV was a class Q planet located somewhere in the Alpha or Beta Quadrants of the galaxy. Near the border between Federation and Klingon space, Delta Canaris IV was the fourth planet in the Delta Canaris star system, and was within subspace communication range of Starbase 16.
This planet was discovered three years into the Federation starship USS Enterprise's five-year mission. On stardate 4720.1, the Enterprise began conducting a mapping survey of the planet which was interrupted by an emergency on Alnath II. The survey and primary contact with the intelligences there wasn't completed until stardate 4769.1.
Delta Canaris IV was a high-gravity planet that emanated violent gravitic waves which required constant orbital corrections be made for any ship near the planet. It had a methane atmosphere and resembled Jupiter, even to the large red spot.
Sensor readings were positive for lifeforms, though in a part of the life-spectrum indicating beings unlike any previously discovered by a Federation starship. Computer analysis of these sensor readings indicated wafer-thin lifeforms similar to a sheet of paper. These life-forms were slightly larger than a humanoid hand and less than a millimeter thick, due to the intense gravity of the planet. Their exact thickness fluctuated due to food intake, movement and other factors. The analysis indicated a 94.2% probability that they were sentient life.
The Enterprise even detected distinct roadways, structures believed to be cities and even indications of a trade spanning the ammonia ocean. First contact was made using techniques that established new standards to be used for primary-contact for many years to come. (TOS novels: The Klingon Gambit, Mutiny on the Enterprise)