Time travel Time travel is having the ability to or the act of traveling forward or backward in time , thus breaking the seemingly irreversible flow of time . The study of this phenomenon is one of the focuses of temporal mechanics . Alterations to historical events can cause , among other things , alternate timeline s and realities . As late as 2154 , time travel was deemed impossible by the Vulcan Science Directorate . ( ) The United Federation of Planets had some form of time travel ability since at least 2268 . It is possible that at least some of the regulations regarding time travel trace their origins back to this date . However , capability at this point was most likely inaccurate , making any attempt at time travel experimental and dangerous . In addition to the Federation , the Borg Collective , Bajoran s , and Klingon Empire were known to have some form of time travel capabilities . ( ; ; ) History . Overview . A historical research in 2268 suggests the Federation was capable of controlled time travel and used this ability at the very least for research purposes . ( ) As of 2378 , at least forty different instances of some form of time travel had been noted in Federation records . Technologically speaking , the Federation ' s capabilities concerning time travel , for the most part , remained unclear . In the 25th century , time travel was mostly possible but still risky . ( ) As of the 26th century , historians and anthropologists used time - travel pod s to travel through time to observe historical events . ( ) In the 29th century , the Federation has the ability to scan time as well as space , and travel back ( and presumably forward ) in time to attempt to fix issues and anomalies . ( ) Events . Crewman , an alleged time traveler from the 31st century , showed Jonathan Archer a group of time - traveling anthropologists from 2769 observing the building of the pyramid s of Giza . ( ) The , after being transported to another universe in late 2256 or early 2257 as a result of difficulties navigating the mycelial network , returned to her original universe nine months later . Her crew ended the shortly thereafter . ( ) The first experienced time travel in 2266 when an emergency cold start of its warp drive slingshot the ship and crew 71 hours into the past . ( ) In 2267 , after an encounter with a black star , the " Enterprise " was hurled three hundred years into the past . Eventually , the " Enterprise " s science officer Spock devised a method for returning the " Enterprise " back to its original period . ( ) Though other instances of time travel had been noted , this appears to be the first instance of controlled time travel by the Federation . Later that year , officers Kirk , Spock , and McCoy traveled to Earth ' s early 20th century and back via the Guardian of Forever . ( ) Sometime in 2268 the " Enterprise " traveled back in time , using the light - speed breakaway factor , to 1968 on a historical research mission . ( ) In 2286 , Admiral James T . Kirk and his senior staff took a stolen Klingon Bird - of - Prey back in time to the year 1986 to retrieve a pair of then ( 2286 ) - extinct humpback whale s to save Earth from destruction by an alien probe . ( ) In 2371 , Captains Jean - Luc Picard and James T . Kirk used the Nexus as a means of controlled time travel , going to just before the destruction of the Veridian star , which Picard intended to save . ( Picard arrived at the Nexus from just after the destruction of said star , whereas Kirk arrived from some 78 years before ) . ( ) Data , unknowingly at first , traveled back in time to Earth circa . 1900 while investigating an alien species that was later found to be ingesting the neural energy from humans of that time period . The aliens acquired their sustenance by travelling through a portal back to that time and place from Devidia II , and were able to shield their presence from outsiders by being slightly out of temporal sync with everyone else , disguising their presence further by taking advantage of a local cholera outbreak . Picard , Riker , Crusher , La Forge , and Troi soon followed to retrieve Data and assess the situation . As the " Enterprise " crewmembers covertly endeavored to stop the aliens and return to their own time , Samuel Clemens was suspicious of them , and was accidentally sent to the 24th century with the " Enterprise " crewmembers ( except Picard ) when they used the alien portal to return to their own time . Luckily , Clemmens was able to go back through the portal and retrieve Picard , returning each man to his own time period before the " Enterprise " destroyed the aliens and their portal . ( ) Twice , Q took Picard back in time ; once when Picard lay dying in a Starbase Medical facility during a replacement of a defective artificial heart that he received as a result of a a Nausicaan knife being stabbed through his heart immediately after Picard had graduated from Starfleet Academy on Starbase Earhart ( ) and another time to the beginning of life on Earth and also back and forth in Picard ' s lifetime . ( ) During a transporter accident above Earth in the caused by chroniton particles being accidentally fused to the ship ' s hull , Benjamin Sisko , Julian Bashir , and Jadzia Dax were sent back in time to early - 21st century , just before the Bell Riots . This caused the Federation and Starfleet to vanish in the present , after the time travelers ' interference leads to the death of Gabriel Bell before his crucial role in history . Only the " Defiant " was left protected by the chroniton particles . Sisko took on the identity of Gabriel Bell to ensure that he was remembered for saving hostages during the events , and ultimately allowing the Federation to come into being over a century later . ( ) While on a trip to Earth to take Nog to Starfleet Acadamy , Quark , Rom , Nog , and Odo were accidentally propelled back to circa . 1950 , crashing near Roswell , New Mexico , due to a sabotaged warp core on the ship that had been given to them by Quark ' s . They were able to return to their own time using the reaction between kemocite and the radiation of a nuclear explosion on Earth . These events - which included Quark attempting to alter the timeline by selling goods to the United States of America during the Cold War , and the Ferengi subsequently being interrogated on the suspicion that they were secretly planning an invasion - were kept secret from the public on Earth at the time . ( ) Akorem Laan , a poet and seer from Bajor ' s past ( which history had recorded had mysteriously disappeared ) was sent to the future by the Prophet s , believing he was the Emissary of the Prophets . Ultimately , Sisko convinced the Prophets to send Laan back into his own period . Laan later went on to finish one of his prophetic poems , which Kira remembered as unfinished , after Laan had disappeared . Sisko points out that the ending of the poem had appeared in databases , along with new history of his life after his return to Bajor . Kira wonders why she could remember the previous timeline , if said previous timeline had been wiped out . Sisko commented that time works in mysterious ways whenever the Prophets are involved . ( ) Quinn took the back in time to the Big Bang to hide from Q . ( ) In 2373 , the , commanded by Captain Sisko , traveled back in time to 2268 via the Bajoran Orb of Time , in an attempt by Arne Darvin to kill James T . Kirk and change the timeline . The crew of the " Defiant " stopped Darvin without any notable damage . Major Kira found a way to use the Orb to get the " Defiant " and its crew back to its own time . ( ) Around Stardate 50814 . 2 in 2373 , the " Defiant " became stuck behind a barrier on a planet in the Gamma Quadrant , where they met the inhabitants who told them they were the descendants of the crew of that crashed on the planet two hundred years in the past . With foreknowledge of the crash , the crew surmised that if they escaped that fate , the timeline would collapse and everything on the planet cease to exist . The descendant of Jadzia Dax , Yedrin , surmised that it would be possible to save their colony , due to an energy discharge that had hit Major Kira , which had created a subspace doubling effect , and for an instant created corresponding quantum duplicates of every molecule in her body . By amplifying the doubling effect through modifications to the " Defiant " , they could make a quantum duplicate of the entire ship , and this second ship would then be the one that would crash on the planet preserving the original timeline . However , the other " Defiant " would be able to escape as well . However , Yedrin had falsified information in his plan , with the intent of making sure that the original ( un - duplicated ) single " Defiant " would crash on the planet , thus ensuring that the colony would continue to exist . The " Defiant " crew ultimately made the decision to sacrifice the ship by flying into the temporal anomaly , in order to save the eight thousand colony members . However , the ship ' s flight plan was changed by the Odo who lived on the colony so that it would clear the barrier , the future Odo wanting to save Kira ' s life . This erased the settlement and all of its ' inhabitants from the planet . ( ) Kira used the Orb of Time to learn about her mother ' s life on Terok Nor . Before she began her orb experience , she was warned not to interfere with the timeline by Sisko . Kira nearly assassinated her own mother and Dukat , but changed her mind at the last moment . The orb then returned her to the present . ( ) During a visit to the planet Golana with her family , Molly O ' Brien was accidentally sent three hundred years into the past via a time portal created by the planet ' s long - lost civilization . She was retrieved by her parents , but was now a teenager reduced to a feral mindset , forcing them to use the portal to send her back . However , their subsequent use of the portal sent the teenage Molly back to shortly after her past self arrived in the past in the first place , allowing her to send her past self back to the present . Shortly after saving the younger Molly , the older Molly ceased to exist , vanishing from existence as the timeline corrected itself . ( ) Also in 2373 , an encounter with the 29th century timeship " Aeon " threw " Voyager " back to 1996 , while the " Aeon " crash - landed in 1967 and was discovered by Henry Starling , who used its future technology to make himself rich . History was corrected when Captain Janeway destroyed the timeship before it could travel to the future and accidentally cause a temporal explosion . " Voyager " was returned to the correct time by an alternate version of the " Aeon " from the correct timeline . ( ) An alternate future version of Janeway ( from 2404 ) traveled back to 2378 through the use of a chrono deflector to bring " Voyager " home from the Delta Quadrant sixteen years earlier than it had arrived in that alternate future . This future Janeway was killed in the attempt but succeeded in returning " Voyager " home and even delivered a crippling if not fatal blow to the Borg . ( ) In 2387 , Nero and Spock were sent back in time through a Red matter black hole which had prevented a supernova from destroying the galaxy ( but not before it had destroyed Romulus in the process ) . Nero was sent back to the past to 2233 , inadvertently creating a new spacetime continuum where he destroyed the . He and his crew then went into hiding for twenty - five years awaiting Spock ' s arrival . Spock arrived in Nero ' s new timeline in 2258 . Nero destroyed , while Spock watched from . The crew of the with the help of , stopped Nero from destroying Earth . ( ) Temporal Cold War . The events of the Temporal Cold War further complicated the understanding of Federation time travel capabilities . As of the 28th century , a time traveling faction represented by a mysterious individual , could only communicate and exchange information and technologies through time , appearing as non - corporeal entities . By the 29th century , this technology was perfected to allow physical travel . According to a Temporal Enforcement Agent from the 31st century named Daniels , all time travelers were bound by the observance of strict procedures set forth in the Temporal Accord s . Daniels stated that the Temporal Accords were enacted after time travel was developed by all time travel - capable species to prevent catastrophic tampering with the timeline . In 2153 , the Sphere - Builder s , a group previously thought to possess the ability only to examine alternate timelines , sent Xindi - Reptilian s back to 21st century Detroit to develop a bio - weapon to destroy the Human race . ( ) Ultimately the war ended when the Na ' kuhl returned from an alternate 1944 ( created by their very actions ) and caused the Cold War to become a war with time - travelers changing time as they liked . Daniels brought " Enterprise " and Archer back to 1944 to stop Vosk , leader of the Nak ' uhl , from returning to the future . With the help of Silik , a member of another faction of the Temporal Cold War , Archer shut off Vosk ' s compound ' s shields , allowing " Enterprise " to destroy it and thus destroying the temporal conduit and killing Vosk just as he was about to travel back to the future . Daniels pulled Archer to a place where they watched the time stream as all of the events that occurred when the Temporal War were undone and time reset itself to normal . Archer refused to have anything to do anymore with Daniels ' " damn Temporal Cold War " and Daniels agreed , claiming it was finally coming to an end thanks to Archer ' s actions . ( ) Apocrypha . In the novel " Ishmael " , Captain Spock embarked incognito aboard a Klingon ore transport , refitted with time travel capacity . The ore transport managed to go back to 1867 Earth after an acceleration close to a white dwarf near Starbase 12 . The was modified to follow the ship to 1867 , becoming the first instance that a Federation ship utilized intentional and controlled time travel . In the video game " " for the Super Nintendo , the computer mentions several temporal near - catastrophes in the 23rd century : the New York incident , the above - mentioned " Ishmael incident , " and the " Eyeglass Loop Paradox " referring to what Kirk did in " Voyage Home " with his glasses . The " " novels " Watching the Clock " and " Forgotten History " go into detail about the principles of time travel , as well as the hows and whys of the various time travel incidents in " Star Trek " s history . The most significant of these demonstrates how Starfleet became aware that history could change - previously they had assumed that changing history just created an alternate timeline that those who changed history happened to get ' stuck ' in - ; when the DTI created " Timeship One " with the intention of deliberately travelling three days into the future , a future version of the ship appeared in their time thirty - two hours before it was due to launch , the crew all dead or dying from an accident that had occurred when they overshot . With this discovery postponing the planned launch , the future " Timeship One " and its crew disappeared once the time of the original launch had passed , confirming that history could be changed .