T'Pol's World was a large gas giant and was noted as the as the largest such planet within the borders of the United Federation of Planets in the 24th century. This world was named for the 22nd century Vulcan space explorer, T'Pol.
The Klingon orbital skydiver K'Thale was noted to have disappeared whilst performing a sky diving over T'Pol's World. Legend states that he fell through a wormhole and trapped to fall for all eternity. (TOS novel: Captain's Peril)