Tycho IV was an uninhabited planet in the Tycho system. In 2257 and 2268, Starfleet starships visited Tycho IV.
- The Tycho star system was close enough to the Romulan Neutral Zone that the Farragut 's executive officer was wary of sending out a distress signal. (Debt of Honor)
On the USS Farragut's visit in 2257, a dikironium cloud creature killed over 200 Farragut personnel, including the Farragut's commanding officer, Steve Garrovick. Then-Lieutenant James Kirk survived the ordeal.
In 2268, now-USS Enterprise Captain Kirk returned to Tycho IV to determine if it was the cloud creature's home. Kirk and Garrovick's son, Steven, beamed down with an antimatter bomb. The bomb destroyed the creature and ripped half of Tycho IV's atmosphere away. (TOS: "Obsession")