Hodunk was the third planet of the Votannis star system, located in Federation space in the Alpha or Beta Quadrant. It had a single moon and was one of two class M planets in its system, the other being Bensonia.
The dominant lifeform on the planet was the Selm, an intelligent race of cetaceans who inhabited Hodunk's oceans. They were similar to Terran porpoises, and like them they were playful and friendly. However, the Selm possessed an advanced civilization despite not having created a single artifact. Their language was equally advanced and highly complex, relying on a wide range of sounds transmitted through water. By the late 23rd century, universal translators did not allow for conversation with the Selm beyond that of crude pidgin.
The Selm were first discovered by the Federation when the USS Kitty Hawk was carrying out a routine survey of Hodunk. The Prime Directive automatically protected the Selm, and a team of fifteen Federation scientists were then stationed on the planet to study them.
The people of the neighboring Federation colony of Bensonia proposed colonizing Hodunk with the aim of keeping criminal elements from exploiting it. Since Hodunk was already inhabited, with the Selm protected by the Prime Directive, the colonists were informed that they could not settle the planet. Regardless, settlers did arrive, and the scientists protested to the Federation Council, where the matter sat under consideration. Thankfully, the colonists' settlement was far inland and did not rely upon the oceans for its resources, and so they had no apparent effect on the Selm.
The Selm, meanwhile, appeared unconcerned with the goings-on of the new inhabitants. They were too busy to care about the affairs of the surface-dwellers, who were regarded as being only semi-intelligent due to their poor language skills.
Hodunk had a total surface area of 642,424,260 square kilometers and, with 21% land mass, a total land area of 134,909,090 square kilometers. Approximately 18% of its makeup was normal metals and 7% was radioactive elements, and it had only trace amounts of gemstones, industrial crystals and special minerals. It had a terrestrial atmosphere and a tropical climate, with a 21-hour day.