Hyralan, also known as Alpha Caeli, was a star system in the Hyralan sector, Beta Quadrant. Hydralan was an alternate way of spelling this system's name.
Components[]
Stellar system[]
This was a binary star system. The primary Alpha Caeli A was a F-type dwarf. The companion Alpha Caeli B was a red dwarf. (ENT: "Cold Front")
History[]
In 2257, during the first Federation-Klingon War, this system was occupied by the Klingons. (DIS: "The War Without, The War Within")
Stellar cartography[]

Alpha/Beta Quadrant Overview (2256)
The Hyralan system was visible from Earth constellation Caelum. This system was approximately 66 light years from Sol.
In the 2150s, this system's position was labeled on an United Earth star chart which was displayed in several crew and guest quarters aboard the Enterprise. (Star Trek: Enterprise, set decoration)
In 2256, this system was labeled on the star chart "Alpha/Beta Quadrant Overview" in the ready room aboard the USS Discovery. (DIS: "Magic to Make the Sanest Man Go Mad")
In 2259, the location of this system was labeled on a stellar cartography chart that was seen on the USS Enterprise's ready room viewscreen. This system's symbol had a blue color, indicating that it was affiliated with the United Federation of Planets. (SNW: "Strange New Worlds", "Spock Amok", "A Quality of Mercy")
On stardate 1292.4, the location of this system was labeled in a chart used during a Section 31 Alpha Team briefing. (Star Trek: Section 31)
The system's location was labeled in a Federation star chart that was in Fleet Admiral Kirsten Clancy's office at Starfleet Headquarters in 2399 and on the bridge of the USS Titan-A in 2401. The Hyralan system was in or near to Federation space. (PIC: "Maps and Legends", "The Next Generation", "Disengage")
In 2401, this system's position was labeled on a star chart used by Captain William T. Riker during his attempt at finding the last known location of the SS Eleos XII. (PIC: "The Next Generation")

The location of Hyralan labeled on a star chart (3190)
In 3190, the location of Hyralan was labeled on a star chart used by Commander Paul Stamets for tracking the movement of the Dark Matter Anomaly through the galaxy. (DIS: "The Examples")
Appendices[]
Background information[]
This star system was only mentioned in writing.
On both Clancy's and Stamet's star charts, this system's name is spelled as "Hydralan".
Information on this system was derived from the episodes, the reference works Star Trek: Star Charts and Stellar Cartography: The Starfleet Reference Library, and real-world sources. The reference works were used extensively in the creation of star charts seen in Star Trek: Discovery, Star Trek: Picard, Star Trek: Strange New Worlds, Star Trek: Prodigy, and Star Trek: Lower Decks. The real-world information added to the article was current as of 2025.
The Hyralan sector was referenced in the Star Trek: The Next Generation episode "Gambit, Part II".
The star chart seen in the series Star Trek: Enterprise made its first appearance in Crewman Daniels quarters in "Cold Front". It was also seen in several other episodes of the series, from 2151 to 2154. (For more information, see Federation star charts#United Earth Alpha/Beta star chart)