The Deltans are an extraterrestrial humanoid species from planet Delta IV and are members of the United Federation of Planets in the 23rd century. They physically resemble humans with smooth skin and no body hair except for eyebrows. They are known for their peaceful, unified culture, emotionally balanced nature and open sexuality. However, Deltans who serve Starfleet are required to swear an oath of celibacy to not get involved in relationships of other species. It is likely that Deltans are telepathic to some extent. They are known to have the ability to relieve pain with physical contact, although the effects are purely psychological and don't have an actual healing effect.