Temporal rift A temporal rift is a distortion in the spacetime continuum , which can allow for temporal displacement through space and time . Encounters . In 2344 , the drifted through a symmetrical temporal rift , which itself was formed through the intense energy discharges of weapons fire as the ship defended the Klingon outpost at Narendra III from a Romulan attack . Emerging 22 years later , the " Enterprise " - C encountered the " Enterprise " - D , the vessel ' s immediate successor . Sensor readings taken by the " Enterprise " - D indicated that the temporal rift was the formation of a Kerr loop from superstring material , and that the energy from the weapons fire was the catalyst for the rift . The surviving crew of the " Enterprise " - C discovered that , in their absence , negotiations with the Klingon Empire had broken down , and the Federation was on the brink of losing a twenty - year - long war with the Empire . Based on the unique perception of Guinan , the " Enterprise " - D crew realized that , as a result of the " Enterprise " - C traveling through time , an alternate timeline had been created , and that the " Enterprise " - C had to be returned through the rift , where their heroic sacrifice in defense of the Klingons would avert the war . Although returning to the battle would mean their almost - certain deaths , the " Enterprise " - C crew elected to return , and arrived at almost the exact moment from which they had originally departed . The " Enterprise " - C ' s actions in the past had the effect of returning the timeline to normal , leaving the crew of the " Enterprise " - D with no memories of what had transpired in the alternate timeline . ( ) In the 29th century , Federation timeship s utilized artificially - generated temporal rifts to travel through time , as part of their efforts to protect the timeline from temporal incursion s . One such rift was encountered by the crew of the in 2373 , when Captain Braxton traveled back in time in the " Aeon " to destroy " Voyager " , believing that they would be responsible for a devastating temporal explosion which would destroy all of Earth ' s solar system . Countering Braxton ' s attack , the " Voyager " crew destabilized the rift , which pulled both ships in and sent them back to Earth , Braxton to 1967 , " Voyager " to 1996 . While there , they discovered that the " Aeon " had been stolen by an industrialist named Henry Starling , who was planning to take the timeship to the 29th century , where he would inadvertently cause the explosion . As Starling launched the " Aeon " , Captain Janeway managed to destroy it with a manually - launched photon torpedo moments before Starling could enter the rift , an act which had the effect of creating a new timeline in which the explosion never occurred . Moments after Starling ' s rift dissipated , a new rift formed , created by Captain Braxton ' s counterpart from the new timeline , who traveled back to escort " Voyager " to its proper place and time . ( ) In 2404 , Janeway , by then an admiral , generated a temporal rift using a time travel device called a chrono deflector , which produced a tachyon pulse which Janeway directed to the Delta Quadrant , the year 2378 . Traveling through the rift in a shuttlecraft , Janeway encountered " Voyager " , and instructed her counterpart to seal the rift using an antitachyon pulse . In the past , Admiral Janeway successfully collaborated with the " Voyager " crew to change history and return " Voyager " to the Alpha Quadrant much sooner than it would have without the admiral ' s intervention . ( )