The Star Trek: Voyager Wikipedia article says:

(...) show is initially set on the other side of the Milky Way galaxy, 75,000 light-years from Earth (...) and (...) Voyager to make the estimated 75-year journey home.

This is confirmed by Captain Janeway, who says in the first episode, that (I don't have access to direct quotation) "even with maximum speed, our travel home will take approximately 75 years" (unless they find some "shortcuts"). The general assumption here is, that Voyager will be travelling approximately 75 years until it reach Earth.

In Warp drive Wiki article, The Next Generation onwards section it is said that:

The Intrepid-class starship Voyager has a maximum sustainable cruising speed of warp 9.975.

According to my calculations (correct me, if I'm wrong), 9.975 warp is around 1680 times light speed. This theoretically means, that traveling entire year with constant maximum speed would allow Voyager to pass 1680 light years, not 1000 (not mentioning these shortcuts, they used like subspace corridors, trans-warp technology etc.).

This means, that Voyager would actually need only around 45 years to reach home (pass 75,000 light years distance). It would be impossible to travel all the time at maximum speed, but that would be compensated by using "extra additions" (subspace corridors, trans-warp etc.).

What am I missing?

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    There is a pretty radiatively challenging super-massive black hole near the center of the galaxy. I would imagine that it is much more dangerous than run-of-the-mill black holes that are millions of times smaller. They might have to take a curved path to avoid it. Also they likely want to go along a path of semi-habitable planets (galaxies have habitable zones just as solar systems do) so they can replenish or stop if they have to. They like to explore sol-type stars to meet new civilizations. These push it to be not a straight line path. Commented Jul 29, 2015 at 20:30
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    @EngrStudent Don't forget the barrier around the galactic core.
    – JAB
    Commented Dec 1, 2015 at 14:02
  • 3
    There's always a Borg Collective or Dominion or the occasional empire that seems to be in your way no matter how much you try to avoid them. Commented Aug 8, 2016 at 3:55
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    There's "sustainable," and then there's "sustainable for decades and decades." I think the assumption is that they wouldn't be able to constantly run at max for THAT long. Commented Aug 8, 2016 at 16:32
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    Star Trek: The Ship that was Flung Far Away and Came Home On Cruise Control wouldn't be very exciting.
    – PhasedOut
    Commented Oct 19, 2017 at 19:12

9 Answers 9


They were (presumably) using the old warp scale. From later in the Wikipedia article you linked:

Exact velocities were given in a few episodes, one being "Relativity", where Kathryn Janeway describes Voyager's velocity at warp factor 9.975. Voyager was about 70,000 light-years away from home, and crew would often use "75 years" as the time it would take to get back home at top speed. This means the Voyager series used the old method of Warp calculation. 70,000/9.9753 is roughly 71 years. Accounting for delays to refuel, repair, restock and downtime, 75 years is a logical rounding.

  • 1
    in the season 2 episode the 37s Tom Paris states that Voyagers top speed is warp 9.9 or approximately 4 billion miles per second which is a little over 20000 times the speed of light
    – severa
    Commented Mar 13, 2014 at 5:01
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    @severa That would clearly mean, that they would return home after less than four years or sth. And that (probably) clearly mean, that each Star Trek eposiode's writers had no bloody idea, what are they writing or talking about. Was memory-alpha, memory-beta or any other Start Trek good quality source available at that time? Maybe episode writers should have own "wiki" to compare results they show in every episode? :]
    – trejder
    Commented Mar 13, 2014 at 20:40
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    From what I remember running @ 9.9 would damage Voyager, for instance even a top of the line sports car couldn't be ran at maximum speed continuously for long periods of time. Eventually the stress and heat from extreme speed would put too much wear and tear on the engine.
    – Jared
    Commented Jul 21, 2014 at 4:24
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    A Ferrari at top Speed will empty it's tank in 60 miles or so. The mpg decreases severely as you get to the limit. Same applies to federation ships.
    – user16696
    Commented Jun 28, 2015 at 20:59
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    From TNG episode The Chase: Captain's log, stardate 46735.2. Our frequent use of high warp over the last few days has overextended the propulsion systems. We are finishing minor repairs before returning to Federation territory. That's just high warp for one episode, and they shut down the core for maintenance. Voyager had to juggle maintenance with stops for fuel & energy resources, food for the crew, and anomaly investigation. On a perfect week, we have to think maybe there's an efficient stretch or two where they don't run out of 1 thing prematurely and have to stop. Commented Jul 17, 2015 at 19:14

"According to my calculations (correct me, if I'm wrong), 9.975 warp is around 1680 times light speed."

I think your numbers are wrong, and I also think the wikipedia article is wrong to suggest they were using the old-style warp scale (they give no source for this claim, it seems to be a speculation by a random wiki editor). The article at http://en.memory-alpha.org/wiki/Warp_factor notes that "In Star Trek: Voyager Technical Manual (pp. 12 & 13) several other speed equivalents are established: Warp 9.6 is 1,909 times the speed of light." So 9.975 must be even faster than that. The Voyager Technical Manual was an unpublished guide for writers on the show, you can see it online at http://www.cygnus-x1.net/links/lcars/star-trek-voyager-technical-manual.php ...p. 12 has the part about Warp 9.6 being 1,909 times light speed, but also note that p. 6 says "Maximum sustainable speed is Warp 9.2", and two sentences later says "Even at the incredible speeds afforded by warp drive, Federation space is still some 75 years away for Voyager." So, the natural implication is that the writers of the Technical Manual meant that it would take 75 years at Warp 9.2. Page 12 also notes that "The ship can exceed Warp 9.9 for only a few minutes."

The wiki article probably got its claim of a sustainable speed of Warp 9.975 from the episode "Caretaker", where the character of Stadi says of Voyager "Intrepid class. Sustainable cruise velocity of warp factor nine point nine seven five", but it's possible this was a mistake on the part of the writers (not checking with technical consultants Michael Okuda and Rick Sternbach), or that Okuda and Sternbach just changed their minds about the top sustainable speed later on. Either way, you could easily retcon it as just a mistake on Stadi's part, or that Stadi was using "sustainable" to mean something different from the technical manual (perhaps Voyager could 'sustain' that speed for a few minutes, or even just a few seconds).

One other consideration which may be relevant: the Star Trek: The Next Generation Technical Manual gives on p. 55 various "approximate values for integer warp factors" (in multiples of c, the speed of light), but then goes on to say:

The actual values are dependent upon interstellar conditions, e.g., gas density, electric and magnetic fields within the different regions of the Milky Way glaxy, and fluctuations in the subspace domain. Starships routinely travel at multiples of c, but they suffer from energy penalties resulting from quantum drag forces and motive power oscillation inefficiencies.

edit: the "Warp Drive Capabilities" section of the Intrepid Class article on memory-alpha notes the confusion surrounding various "top" speeds for Voyager, and what they would translate to in terms of multiples of light speed:

According to Star Trek: Starship Spotter and the Star Trek: Voyager Technical Manual, warp factor 6 is the actual cruising speed for the Intrepid-class. "Dragon's Teeth" would support this, as the episode begins with Voyager cruising at warp 6, as does "Pathfinder", in which the average speed of warp 6.2 was estimated as the speed Voyager was traveling towards the Alpha Quadrant. According to the text of the Technical Manual, warp 9.2 is supposed to be the maximum sustainable speed, while warp 9.6 is the rated top speed and warp 9.9 is a speed that can be sustained for only a few minutes. In a speed chart, the Manual contradicts itself by giving instead warp 9.975 as the top rated speed, that can be maintained for 12 hours. According to the chart, the 9.975 speed corresponds to a velocity of 3,056 times the speed of light. This would be much slower than what warp 9.9 was canonically established to be in "The 37's", well over twenty-one thousand times the speed of light.

Canonically in "Caretaker", "Relativity" and "Barge of the Dead", Voyager is specifically stated having the maximum cruising speed of warp 9.975. In the episode "Threshold", when accelerating to and attempting to match warp 9.97, the computer warned of imminent structural collapse. In the episode "The Swarm", it is only possible to maintain warp 9.75 for twelve hours. It is also stated in the episode by Chakotay, that Voyager is not able to sustain its maximum warp at that time. The maximum warp is however used in several episodes before and after "The Swarm" for extended periods. Finally the maximum warp is given a canonical speed estimate in two episodes. In "Friendship One", the ship is capable of crossing 132 light years in one month at maximum warp. This turns out to be only about 1,554 - 1,721 times the speed of light. In "Scorpion, Part II", the ship is capable of crossing 40 light years in 5 days at maximum warp. This in turn is 2,922 times the speed of light. The later estimate is closer to the 3,056 times the speed of light mentioned in the Manual.

The reasons for Voyager's lack of ability to maintain optimal warp speeds are given in the Star Trek: Voyager Technical Manual. There were very limited refueling and overhaul assets available during the journey, and the crew had to allow the engines down time for cooling. Furthermore according to the Manual, the 75 year travel time figure established in "Caretaker" was never meant to be a realistic estimate. It was based on the assumption that Voyager would maintain warp 9.6 or warp 9.99 and travel uninterruptedly directly to Earth. A more realistic figure of two to four hundred years to cross the Delta Quadrant and into the Beta Quadrant was the more realistic predicament at the beginning of the series.

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    YEah, this makes more sense than Stadti reverting to the old scale. Especially since the old scale had Warp 10 not be infinite speed, which is explicitly stated to be true in Voyager.................................................................................................................................................................................................................................... If anything was changed about the Warp scale, I would think it was recalculating based on actual observations or changes made in the Warp engine to not tear up subspace.
    – trlkly
    Commented Oct 4, 2015 at 0:54
  • I would say that any changes with regards to what the top speed is could be put down to the drive is damaged and repaired and altered throughout the series and it's all jerry rigged so this could change it constantly. Also the design is a new design and it is possible that it messed up. And the ship was never meant for a long term deep space mission so it likely wasn't even remotely prepared for such a journey all of which limits how much they could push the engine.
    – Durakken
    Commented Aug 8, 2016 at 4:23
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    It should also be noted that warp engines tend to be rated for their absolute maximums. As we see again and again throughout multiple series, the closer a starship gets to max speed, the more strain on the engines. A warp 5 engine can't do warp 5 for long, but can sustain for brief periods. So max speed isn't sustainable long term.
    – Ted Miller
    Commented Jan 5, 2019 at 20:48

We do have a few instances from TNG stating that Warp speed of 9.2 and 9.4 are much faster than what was stated for Voyager. Also, even Paris himself mentioned in 'The 37's' episode that Warp 9.9 is 'about 4 billion miles per second', which comes out to 21,473 times the speed of light.

From TNG in Season 1, 'Where no one has gone before' episode, Data stated that the Enterprise-D would take over 300 years to traverse 2.7 million Ly's at maximum Warp. From 'Encounter at Farpoint', we learned that the maximum Warp velocity (which puts strain on the engines) the Enterprise-D can achieve is Warp 9.2 (though they were able to match Q's net which was travelling at warp 9.8 'at an extreme risk' - obviously they were unable to sustain 9.8 for very long, so 9.2 was at the time the maximum [cruising?] limit).

In 'Q Who', the Q has thrown the Enterprise-D 7000 Ly's from their previous coordinates. Data estimated that at maximum Warp velocity, the ship would need 2 years and 7 months to reach the nearest starbase (which granted we don't know how far away it was from their relative position, BUT if we estimate that the Enterprise was likely on the (or close to the) border of Federation space to begin with, then it is possible the starbase in question was about 6000 to 7000 LY's away).

So, Warp 9.2 from Season 1 would equate to roughly 41.2 Ly's per day (or 15330 times the speed of light - with a reasonable estimation that crossing 2.7 million Ly's would last about 305 years).

In 'Q Who', The Enterprise-D was able to achieve Warp 9.8 easily enough on Picard's orders, whereas 9.9 was established as their 'maximum'.

So, if Warp 9.9 from ‘Q Who’ takes 2 years and 7 months to traverse 7000 lightyears, that puts it at roughly 2800 times the speed of light (if I'm not mistaken) - a much greater reduction in speed from Season 1, which continued to reduce until it landed at 9.975 = about 1000 ly's per year for Voyager (and Ds9 also mentioned this – but even Ds9 was inconsistent at times with its Warp speeds).

Now... I personally find Paris statement about Warp 9.9 being 4 billion miles per second much more in the range of what is possible for the Federation in the late 24th century by the time Voyager was launched and a decent/consistent increase over Warp 9.2 from Enterprise-D. I think it was stated that exponential increase doesn't happen until you pass Warp 9.9, meaning that with every increment past 9.9, the velocity of the ship doubles. So, Warp 9.975 would equate roughly 11452.2 Ly’s per day (if we go by Paris statement of 4 billion miles per second) - and this would allow Voyager to get back to the Federation in just under a week. Incidentally, this speed would mean the ship would traverse 440.46 Ly's every hour (which is 140.46 Ly's faster than Slipstream version 1 maximum velocity of 300 Ly's per hour which the fake Dauntless used). If we go by the speeds from ‘Q Who’ though, Warp 9.9 = about 7.67 Ly’s per day … and 9.97 would be roughly 981.76 Ly’s per day, and Warp 9.975 would be about 1472.64 Ly’s per day (537 513 times the speed of light) – at this velocity, Voyager would take just under 51 days to traverse 75 000 Ly’s.

As for Voyager taking 75 years to get back to Federation space... some people have stated that Voyager used Kirk era Warp scale instead of the revised one from TNG which put Warp 9.975 at those low speeds. What I find more credible as to why it would have taken them that long, is that the Caretaker's pull damaged the ship on a level the crew was unable to repair while so far away from home, resulting in much lower attainable Warp velocities (the ship WAS indeed critically damaged after it was pulled to the DQ).

We even saw that Voyager was unable to sustain high Warp in 'Threshold' episode and the computer said 'nearing maximum warp velocity' [which in this instance would be 9.975 according to the dialogue]. But, voyager was repeatedly stated on the show that Warp 9.975 is its 'top cruising speed' or its 'maximum sustainable cruise velocity'. Maximum cruise velocity indicates that an engine would effectively be able to sustain it indefinitely without trouble... but apparently, this did not carry out. Which leads me to think that Voyager's hull or Warp systems (or both) took heavier damage in transit to the Delta Quadrant which they were unable to isolate or repair in full, forcing the crew to use lower Warp velocities at all times and lowering their top cruising speed as a result – and it was never mentioned.

It wouldn't be the first time that characters said something inconsistent or failed to describe completely. Various individuals kept asking themselves how was Voyager able to destroy various shuttles and always had more to spare… or its torpedo compliment being initially 36 I think which Janeway said there was no way to replace after they are gone.

In short, I think the writers wanted to make things more dramatic while ignoring their technical capabilities. For instance, Voyager could easily replicate various torpedo parts and casing and just assemble the thing without antimatter. Then trade with other friendly species such as the Talaxians or others who had antimatter to spare so they can supply their photon torpedoes as opposed to replicating antimatter (or in emergencies, the crew might have used antimatter from the warp core itself).

Similarly, Voyager made numerous pit stops in uninhabited star systems and harvested raw materials which they probably used for easier replication – matter to matter (as opposed to using direct energy to matter process) that resulted in reconstructed shuttlecrafts. Damaged shuttlecrafts were likely recovered off-screen and then salvaged as much as possible. We’ve seen them building the Delta Flyer after all, so its not beyond their capabilities – albeit I found a distinct lack of automation for Delta Flyer construction a tad unrealistic.

  • 2
    For what its worth, the Star Trek novels (non canon) consistently mention the Enterprise-E maximum sustainable Warp velocity of 9.7 or 9.8 if I am not mistaken, and I recall that the ship was mentioned it would be able to traverse 26 lightyears per day (the day lasting 26 hours in the Federation). This means that the Enterprise-E from the novels can achieve and sustain 9490 times the speed of light. The Warp speeds are highly inconsistent, but I still think that Warp 9.9 = 4 billion miles per second has merit, and it helps explain 'the speed of plot' for some episodes.
    – Deks
    Commented Jun 29, 2015 at 1:05

A very old statement about warp numbers was that the speed expressed as a multiple of c was equal to the cube of the warp number, so Voyager's quoted top speed of 9.975 equated to something just under 1000c. This would have made the 70,000 light year journey an undertaking of something just over 70 years (non-stop).

Out-of-universe, the writers may have based their numbers on the old method mixed with a bit of license to fudge it up to 75 years. After all, if the ship didn't have to stop or detour for an adventure here or there, there wouldn't be much room for weekly stories.


Voyager was 70,000 light years away, warp 10 TOS was 10 cubed, or 1000 times the speed of light. 70,000 light years divided by 1000 times speed of light equals 70 years. Less than a parsec per day. But they would get home - eventually.

I understand speed was limited for literary reasons, to keep space from becoming too small. That didn't bother writers like Doc Smith, whose space ships with their inertia-less drives cruised at 60 parsecs per hour. 70,000 light years? 15 days, vs 70 years. (That would make for a very short series)


In Maneuvers (season 2 ep 11) Torres suggests using the transporter at warp speed which Kim says is 2 billion kilometers per second at 35 minutes in. That surely is not maximum warp - they'd go as slowly as possible. At that speed they'd do 6,671 light years per year and so would do 70,000 light years in a bit over ten years.

I think it is just a matter of the script writers not trying to keep distances consistent. After all they also show stars moving past the spaceship at such a speed during warp - and even when traveling sublight - that they'd be back home in a matter of days. And things like the way boundaries between great star empires are measured so precisely that you move just a few hundred meters and you cross them, and dropping out of warp within kilometers of another ship etc etc. It's just artistic license and you can't make a coherent scientific model out of it all.

  • there's that, and the fact that Warp 9.9 was mentioned by Paris to be 4 billion miles per second. So Kim's statement does have merit. Except, Voyager was thrown into the DQ and in the process severely damaged the hull, engines and Warp core itself. This could have resulted in damage the crew was unable to repair, resulting in lower attainable Warp speeds, and of course, the writers wanted to make things dramatic by keeping the ship 'decades away from home' - which could have been done by having Voyager being thrown millions of ly's instead and taking 7 decades to get back at 9.975
    – Deks
    Commented Aug 26, 2019 at 18:57

You should not compare warp factor speed to the actual speed achieved. The actual speed achieved at a certain warp factor is inversely proportional to the amount of mass/gravity in the area. Voyager would have to go through the center of the galaxy in order to get a direct path to home. However, the center of the galaxy is extremely dense with stars. The fastest route is an indirect one, going around the center of the galaxy, which would certainly add time to the journey. Staying at the same distance from the center would result in a trip distance increase of π/2 times or ~1.57x, but may actually result in a shorter travel time, since you go through the same amount of space faster.

Source: in the movie Star Trek: Generations, Commander Data explains why the ideal path of starships is slightly altered by the blowing up of a star. The reason is because the amount of mass/gravity interference changes slightly.


In Star Trek Voyager s1 ep8 Emanations Cpt Janeway orders Tom Paris to take them away from the rings around a planet. At least 0.6 lightyears. Tom responds after about 2 seconds that it’s done. Simple calculations show that they would travel 1080 lightyears every hour. This will take them home in a bit less than 65 hours...

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    Two seconds on-screen does not necessarily equate to two seconds in-universe.
    – Politank-Z
    Commented Dec 25, 2017 at 11:55
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    You are absolutely correct. In episode 1 of season 2 Mr. Tom Paris tells Mrs. earhart that warp 9.9 is about miles/second. In metric this would be about 6,44 billion km per second. Given the fact that the journey is roughly 6,627x10e17km it would take 3 years and 95 days and 7 hours to get home... I was incorrect at first.
    – Guest
    Commented Jan 4, 2018 at 23:42
  • Plus, Warp 9.9 was not seen as something VOyager can actually sustain. If episode 'Threshold' has any merit, 9.9 was the 'maximum' (definitely not a cruising speed). And, in TNG, no Federation ship was seen to be able to achieve and sustain 9.9 for long periods of time (9.6 was what Ent-D topped out at). Voyager suffered heavy damage from its pull to the DQ. So its possible the ship was unable to reach their sustainable cruise velocity of 9.975 under those conditions. Otherwise, 9.9 = 4 billion miles per second seems more credible.
    – Deks
    Commented Aug 26, 2019 at 19:00

I would say that no one is perfect. But purely from the creative side the 75 years rounds out to make it nearly impossible for most of those living on the ship to be alive when they would reach home. However I can't say how well a ship like voyager would fair after 75 years. Chakotay's maquis ship was in rough shape and if I'm remembering correctly it was 30 yes old. So when you ad aged parts and hull with aged crew. If not for short cuts even at warp 9.975 things will need to be repairs and in the episode "the cloud their energy reserves are down some 22%. Which would cause them not to beable to remain at max speed, and thus require them to find a way yo supliment their energy. I also recall in a later episode its name escapes me. But I remember seven and b'elana worrying about the supply of bio neurol gel Pak's. So the ship pike the crew was in a way a living thing and could not sustane more than an average warp speed of 6.2-6.7. Because like people just because you can run a mile in 9.5 seconds doesn't mean you can run at that speed for 75 miles. Sorry if I got off point. But sometimes the since of something is in the fiction not the science. I love voyager, Janeway is my favorite Captain and there are times when it is required to look at the story with the science not the science in the story.

Hope this helped.

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    Hi Tina, I can tell you've put some effort into this answer, but as it stands I'm struggling to read it. Could you edit some structure into it? Maybe back up some of the claims?
    – AncientSwordRage
    Commented Jun 15, 2015 at 15:28

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