Delphic Expanse The Delphic Expanse was an area of space approximately fifty light year s away from Earth . It was nearly two thousand light years across , according to the Vulcan Ambassador Soval . The Expanse was riddled with a web of dangerous spatial anomalies and was surrounded by a dense layer of thermobaric cloud s , which made navigation extremely hazardous for starship s . Artificially created by transdimensional beings using a vast number of massive spheres , the Delphic Expanse ceased to exist in 2154 , when the Earth starship destroyed them . ( ) History . In 2133 , a Klingon starship attempted to enter the Delphic Expanse . When it reemerged , the entire crew was anatomically inverted but still alive . After this incident the Klingons would not enter the Expanse . Vulcan ships had also entered the Expanse , but only a few had ever returned . ( ) In December of 2152 , the Vulcan ship " Seleya " embarked on a mission to chart the thermobaric clouds surrounding the Expanse . After several days the ship ' s crew reported that the " Seleya " was caught in a subspace eddy and being pulled into the Expanse and contact was lost . The crew of the Vulcan ship " Vaankara " , sent to search for the lost " Seleya " , went insane , killing each other and self - destruct ing the ship after only two days inside the Expanse . After this the Vulcans considered any expedition into the Expanse to be a foolishly risky action . The " Enterprise " later found the " Seleya " adrift , with its crew gone insane due to trellium - D exposure . ( ) When Earth suffered a devastating attack which resulted in the deaths of seven million people in of 2153 , Captain Jonathan Archer received intelligence from the Suliban Cabal ' s mysterious benefactor that the attack had been launched by the Xindi , a race native to the Expanse . With this information , the " Enterprise " embarked on a mission into the Expanse to find the Xindi , in an attempt to prevent another attack which would destroy Earth . ( ) While in the Expanse , " Enterprise " encountered the Triannon s , a native species which regarded the Expanse as the " Chosen Realm , " an area that had been created by supernatural beings they referred to as " the Makers , " in preparation for their eventual return . As they spent more time in the Expanse , the " Enterprise " crew discovered that the Triannon myth was based in fact , and that the Expanse had been created by a race of transdimensional beings who were attempting to reconfigure space to make it habitable for their species as a prelude to invasion . ( ) The crew discovered that this race had constructed a series of massive spheres , each one of which emitted powerful waves of gravimetric energy , which were responsible for the spatial anomalies . Possessing advanced temporal technology which allowed them to examine alternate timeline s , the Sphere - Builders discovered that , in the 26th century , the Federation was destined to finally defeat the Sphere - Builders and drive them back into their transdimensional realm . In an attempt to prevent this future , the Builders contacted the Xindi and led them to believe that Humanity would eventually be responsible for the destruction of their homeworld , and that the only way to save themselves was to destroy Earth first . ( ) In early 2154 , Captain Archer was eventually able to convince the Xindi that they had been manipulated , and entered into an alliance against the Sphere - Builders . " Enterprise " was successful in disabling one of the Spheres with a deflector pulse , causing a chain reaction which destroyed the entire Sphere network . This effectively caused the Expanse to cease to exist , and the thermobaric cloud perimeter dissipated . ( ) Appendices . Background information . The size , mentioned by Soval , presumably did not refer to a spherical diameter of the expanse , as such a huge phenomenon would be a dominant feature within the galaxy . If the size is accurate , it would suggest the expanse was a somewhat flat region of space . In the final draft script of , the Delphic Expanse was said to be nearly a light year across , rather than almost two light years . According to " " ( " Stellar Cartography " p . 17 ; " Federation Historical Highlights , 2161 - 2385 " ) , the Delphic Expanse was located in the Beta Quadrant . This expanse was " " angled some 2 , 000 light years from " top to bottom " within the 10 , 000 light year thickness of the galactic disk " " . According to , this region could be likened to Earth ' s " Bermuda Triangle " . Apocrypha . The novel " Rosetta " establishes the technical scientific name of the Expanse as " the D - 4853 anomaly . " A form of the Delphic Expanse also appears in the alternate reality ( " " Kelvin " timeline " ) in " Agents of Yesterday " , the third expansion to " Star Trek Online " . In the mission " Terminal Expanse " , the player character from the " main " timeline - tasked by Agent Daniels to battle the Sphere - Builders and their mysterious " Envoy " - arrives in the alternate reality in the year 2260 , and joins with Science Officer 0718 and the USS " Yorktown " to stop the Sphere - Builders from creating an Expanse in that universe . " Terminal Expanse " also indicates that the Sphere - Builders have attempted to create Expanses in numerous realities , all with often catastrophic results .