Kryten: Hmm yes, he's giving us 5 hanaka to decide.
Rimmer: How long's a hanaka?
Kryten: Well, curiously enough, it's exactly the same as one Earth minute.
Cat: 5 hanaka! That only gives us 28 hours!
Red Dwarf, "Emohawk"

Fictional universes call for fictional measurements of time. After all, why would an alien culture use the same words for time as an Earth-based culture?

Strangely, 'alien' time units correlate pretty well with Earth time units in the majority of cases. 'Cycle' is the most common of these, usually referring to a year (though sometimes a day).

This can be justified easily enough; aliens probably live on a planet that orbits a star and has a day-night cycle, so they might well have natural units of time corresponding to "day" and "year," though probably not exactly the same length (unless, of course, the planet in question is almost identical to Earth and the star it circles is the same as the Sun, in which case it may be the same distance away and would therefore have about the same length for a year. No accounting for days, though.)

If an alien character doesn't use their own measurements, but instead uses Earth measurements in a jarring manner, they're talking in terms of Two of Your Earth Minutes. If these units are used across multiple worlds or civilizations, they are Standard Time Units. See also Fantastic Measurement System for other fictional units.


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     Anime and Manga  

  • There's an example in the first chapter of Sensei No Bulge: the protagonist is said to be earning 7 quarks an hour, with a footnote saying a quark is worth about as much as a yen (¥7 ≈ $0.09). That's no doubt meant to tell the readers how poor he is, and presumably that's based on purchasing power as opposed to exchange rate, as Earth is implied not to exist in that universe.

     Comic Books  

  • In the Bronze Age, Superman comics stated that Kryptonian time was divided into "dendars", their equivalent of a minute that consists of one hundred seconds, which implies that Kryptonians were very enthusiastic about the metric system.
  • The New Krypton story arc has the Kryptonians using a weird time unit, apparently of an order of magnitude similar to the minute.
  • The Marvel Transformers Generation 1 comic book series introduced two Cybertronian time units: a "Breem" (8.3 minutes) and a "Vorn" (83 years). Apparently, giant shape-shifting robots never bothered with units of time greater than 8.3 minutes and less than 83 years...note 
  • In Paperinik New Adventures we are shown the Evronian time units: the basic unit is the spetung, then we have the secron (ten spetungs), the minutron (100 secrons), the houron (24 minutrons), the dayron (12 hourons, 18 in the rink (final dayron in all monthrons but those of Tamit and Hoxon)), the monthron (15 dayrons organized in groups of 5, it's grossly equivalent to a month of the gregorian calendar and start halfway during our months) and the yearhon (12 monthrons, equivalent of an Earth solar year. Starts on 15 august). Yearhons are grouped into millennia, named after the reigning emperor (implying an emperor can live up to one thousand years, at which point its successor will kill him). Due having been created half-jokingly shortly before the fall of the Evronian Empire, Evronian time units appear only in one story. Also, the Evronian calendar has a couple in-jokes: 15 august (Earth equivalent to the start of the Evronian calendar) was the day of publication of the annual special issue (the Evronian calendar was attached to the 1999 special), and the names of the normal days (po, ra, da, qu, pa) are the initials of the phrase "Poche ragazze da quelle parti" ("there's little girls in your neighbourhood"), a joking answer the staff tended to give to particularly strange fan mails.

     Fan Works  

  • The time system in Ketafa in With Strings Attached (and, later, also in Baravada in The Keys Stand Alone: The Soft World) is some strange thing divided into five big chunks, four sets of five smaller chunks, and 400 smaller units. Times are called, very prosaically, “2-3” or “5-5” or whatever. The four never bother to find out anything about it, and the only time it matters to them is in Keys when they need to be somewhere at a particular time, or when one of the minor magic items they acquire has a time limit. They do, however, get a pocket watch.
    • The clock starts at noon, when all hands are at 1; this is called “All Up,” signals lunch, and is the only known Ketafan clock setting to correspond with any 24-hour clock setting.
    • No calendar, day names, etc. are mentioned at any time, but the inhabitants on both continents refer to “hands” of days or years.
  • In Kyon: Big Damn Hero, Kuyou Suou measures time in terms of number of rotations of a black hole rotating at approximately maximum speed, which is about 1,150 per second.
  • In Plan 7 of 9 from Outer Space a hostile plant alien demands the human authorities hand over twenty gurqs of uranium (a gurq is equivalent to one Earth kilogram) and a hundred geeks of fertilizer (a geek is equivalent to the weight of one sci-fi fan) within one neegath (equivalent to one Earth hour minus 0.0095746338th of a microsecond). There are also neeps, each equivalent to one Hollywood minute: a circumstantially-variable duration of time.
  • Pokémon Reset Bloodlines has this come up with one of the show's longest running mysteries: Ash's age. In fic, Ash himself has no idea how long his journey pre time travel was as per one of the stories ongoing jokes, so he eventually starts to measure the length of time he was traveling in gym battles.


  • Men in Black uses this trope in a grimly comedic way, tossing 'week' in where it really shouldn't go...
    Kay: Arquillian battle rules, kid: first we get an ultimatum, then a warning shot, then we have a galactic standard week to respond.
    Jay: A "galactic standard week?" How the hell long is that?
    Zed: One hour.
  • Coneheads: Seven Remulakian zerls correspond to approximately 16 earth years. Beldar and Prymat are understandably worried when the home planet said it would take that long for a rescue ship to arrive.
  • In Man of Steel, Zod and his followers are sentenced to the Phantom Zone for 300 "cycles". These are persumerly Kryptonian years, but since no matter how much time they measure, Krypton doesn't have 300 of them left, so it quickly become a moot point.


  • Inverted in The Wheel of Time, where a ten-day period is called a week. This is mentioned exactly once in the story, in an offhand mention going something like, "Four more two-day festivals scheduled for this week," leading the casual, non-glossary-reading reader to believe that Robert Jordan was an idiot.
    • Many fans have been confused by the combination of the above and Moiraine's conversation with Nynaeve about when she began channelling, where she asks if Nynaeve experienced certain things in "a week or ten days." So apparently she meant "a week, i.e. ten days".
    • This is due to the fact in Randland most people who aren`t merchants pay little mind to the calendar, preferring to go by seasons. This is so prevalent that most of the viewpoint characters are unaware of the names of the days of the week.
      • Which is understandable since most of those viewpoint characters are from a backwater village in the middle of nowhere, two of them have memories of people who died a long time ago, one has a mental link to animals, and others are from cultures that probably have an entirely different calendar.
  • In Steven Brust's Dragaera novels, a Dragaeran week is 5 days. Humans/Easterners still use seven-day weeks, and even fortnights (14 days), which Vlad (raised in Dragaera) thinks is a really weird period of time to have a name for because it is "...one day shorter than three weeks."
  • Most of L.E. Modesitt's novels, even those in entirely different settings, have "eightdays" instead of weeks and use "kays" for distance.
  • Edgar Rice Burroughs' John Carter of Mars stories. Martian civilization used the following time units: 1 Xat = 200 tals, 50 xats = 1 zode, and 10 zodes = 1 Martian day. Mars has a day almost identical to Earth (24 hours 39.6 minutes), so 1 zode = 2 hours 28 minutes, 1 xat = 3 minutes and 1 tal = .9 second.
  • Gor (based a lot on Barsoom) measures 80 Ihn (seconds) to the Ehn, 40 Ehn (minutes) to the Ahn, and 20 Ahn (hours) to the day.
  • Mercedes Lackey's Heralds of Valdemar books call an hour a "candlemark". In her Obsidian Trilogy, characters from a certain city reckon time in units of "bells", each of which is two hours. The city is chock-full of bell towers that all ring on that interval.
    • The whole "candlemark" thing comes from a real-word form of clock from the medieval period, which was simply a candle made in a length which would (theoretically) take X hours to burn down. The candle was striped in hour-long segments, so you could tell by looking at it how long it had been since you lit it. Obviously there was much potential for imprecision in the real world; in Valdemar they've got it down to a bit more of a science.
    • Valdemar's neighboring countries use other units called "[something]marks" or just plain "marks." They're all on the same order of magnitude, but no two of the same length, leading to some in-universe confusion.
  • The Race in Harry Turtledove's Worldwar series apparently operates on metric time, as their phrase "one tenth of a daytenth" equals out to about fifteen minutes.
  • The giant, moving city on rails in The Inverted World uses "miles" as a measure of time. Though initially confusing, this is eventually explained when it is revealed that the City has to move 1/10 of a mile per day in order to survive; thus, a character might say "a mile ago" to mean "ten days ago".
  • Deliberately averted in the novel based on Nightfall. The author says this is to simplify readng the narrative. So the narrative uses words like "mile" "hour" and so forth. They do specifically say there may not be 60 minutes in an hour.
  • In Isaac Asimov's Robot City series (by Rob Chilson, William F. Wu, Arthur Byron Cover, Michael P. Kube-McDowell and Mike McQuay) the robots use normal time units, but since the days in the titular city are of a different length, the human heroes get metric watches dividing the day into decades and centades.
  • Often used in the Star Trek Novel Verse. For example, 6 human months equals about 4 Vostigye ronds, and nearly 40 Talaxian niziks. A Romulan Veraku is about 63 Earth minutes, and a Siuren is roughly 50 seconds.
    • The novels actually have standardized terms for the full range of Vulcan, Romulan and Klingon time measurements, from seconds through to years. They're used quite often if these races are the POV characters in a given scene.
    • The Aluwnans in Genesis Force use the rather uninspired "instants" and "units" in place of minutes and hours.
  • At one point in the Dragonback series, Alison Kayna notices that the Valahguan "Death" weapons the scout fleet gets hit with cut off after three minutes and 47 seconds, which led her (correctly) to the conclusion that the weapons were strictly a loaner and that the enemy alliance wasn't that firm. Draycos mentions that that would fit, since 3 minutes 47 seconds works out to two birs of Valahguan time measurement.
  • A "week" on Discworld is eight days long. This could, potentially, have caused difficulties with the Discworld Diaries line of humorous datebooks, but the quandry was resolved by saving Octeday for amusing anecdotes and character sketches.
    • It is also canonically established that a year (a full revolution of the Disc) is 800 days and has eight seasons. This is never respected after being established, so a linked system of �short years� of 400 days and 4 systems was retconned in. If you�re going forward along the turtle�s left side in summer in an odd short year, you�ll be going backwards on the right side in an even summer. To keep things simple, each short year has 13 months.
  • In Joan Vinge's The Outcasts Of Heaven Belt, all time units have been replaced by multiples of seconds (megaseconds,gigaseconds), freeing them from dependence on any local rotation or revolution cycles.
  • In the Darkover books, a Darkover day is twenty-eight hours. Why twenty-eight? Presumably (in the author's attempt to retcon this), the original Lost Colony approximated the Earth hour (before they forgot their origin), but adjusted to a new day length.
  • In Journey To The Morning Star, the Etherians measure time in tils, tiltils, soltans, and ladoses. A til is a hair longer than a second. A tiltil is a hundred tils. A soltan is a hundred tiltils. A lados (Etherian day) is eighteen soltans. It's not specified what they call a year, although they also measure orbital cycles, and one full orbit of Etheri Tau around Lado is equal to 422 ladoses.
  • In Wiz Biz series the World measures time in "day-tenths" which is 1/10th between today's sunrise and sunset. Yes, their length varies as the day length changes. Interestingly, the time in Wizard's Keep seems to be in synch with California — "two day-tenths from sunrise" is the same in both places.

     Live Action TV  

  • Trope Namer Farscape's alien characters commonly use 'microt', 'arn' and 'cycle' in place of 'second', 'hour' and 'year' (roughly). John Crichton (the only Earth character in the series) picks up on it, and often counters with nonsense of his own.
  • The original 1979 Battlestar Galactica series used "microns" for seconds, "centons" for minutes (or for hours in the series pilot), "centars" for hours, "sectons" for weeks, and "yahrens" for years.
    • "Yahren" is pronounced exactly like the German Jahren, the dative form of the word Jahre meaning "years". In fact, the plural of "yahren" in old BSG was "yahren". So yes, BSG did just rip off German.
    • In real life, "micron" is slang for micrometre, is one-thousandth of a millimetre, but that would mean that when the Cylon raiders were "ninety microns and closing," they were 0.09 mm away. But seriously, folks, the Viper coordinator probably meant the raiders would arrive in 90 seconds on their present course and speed.
    • The show hung a Lampshade on it in the episode Greetings From Earth where other human space colonists used seconds, minutes, and hours while Apollo said "Wait just a centon!" trying to figure it out.
  • Re-imagined Battlestar Galactica averts this, except for some documents visible onscreen in Armistice Station in the Miniseries, which use original-series terminology. Spoken dialogue and other writings have "years", "minutes", etc.
  • In Doctor Who, Daleks use "rels" to indicate a short period of time, which varies between about one and two seconds from one episode to another.
  • In Babylon 5, Drazi cycle not Drazi week. Cycle Drazi year. It can be assumed that almost all species have their own time units, but the Babylon station runs on Earth time. Some early episodes referred to on-station time in terms of "cycles", but this was dropped in favor of standard Earth time units.
  • Starting with Star Trek III: The Search for Spock and continuing on at least one episode of Star Trek: The Next Generation, Klingon Battlecuiser crews call out the distance to their targets in "Kellecams". (Or "killicams". Or "kilicams". There doesn't seem to me much agreement on the spelling. As they're translating from Klingon, the closest would probably be something like qelI'qam.)
    • Beginning with Star Trek: The Next Generation, stardates were (sort of) standardized to a year being 1,000 units long, with each unit being subdivided into 10 subunits. That would mean that 1 unit is equal to roughly 8 hours, a subunit is roughly 48 minutes, while a day is 3 units. Thus, the launch date of the Enterprise-D, stardate 41153.7, correlates to February 20, 2364 at 5:36 am.
  • Star Trek: Voyager
    • The planet in "Time and Again" used rotations, intervals, and fractions. And Hindu-Arabic numerals.
    • Averted in "Prime Factors" when an alien gives a measurement based on the distance between the sun and her home planet, and Harry Kim mentally converts it to light years.
    • A recently de-assimilated Seven Of Nine once attempted to participate in a conversation regarding children by remarking that "Children assimilated by the Borg are placed in maturation chambers for seven cycles". That went over about as well as could be expected. The exact length of the "cycles" she mentioned was not stated, and considering the nature of the Borg could be anywhere from seconds to years (though probably closer to the latter).

     Tabletop Games  

  • Exalted has a year... that's made up of 15 months and 5 days that are "outside the year", called Calibration. Also, every month is made of exactly 28 days.
  • The Forgotten Realms has the "tenday", which some nations call a "ride." Hilarity sometimes ensues due to confusion, when a person says "two rides" and listeners think they mean two days of riding.
  • Paranoia supplement Acute Paranoia. Alpha Complex used the phrase "half a cycle" for the period between 1 wake-up call and the next (i.e. 1 day). A "cycle" was therefore 2 days.
  • In the old Dungeons & Dragons setting "Hollow World," where the setting lacked a day-night cycle, the basic unit of time was the "march."

     Video Games  

  • The X-Universe series has the "sezura", "mizura", "tezura", "wozura", "mazura" and "jazura". None of them directly correspond to Earth time units. 1 sezura = 1.7 seconds, 1 mizura = 96 sezuras (2 min, 43 sec), and continuing into ever more irregular measurements. X2: The Threat dropped the alternate measurements; the games still use the alternate names, but they correspond directly with standard time measurements, like one mizura being one minute.
  • The Slylandro in Star Control II have "rotation," "Drahnasa," and "Drahn" which are something like their equivalent of days, years, and millennia (not particularly similar in duration to ours though). It would be tricky to decode these except that pretty much everything interesting that's happened on a galactic scale happens in one of three time periods (Quite Recently, A Long Time Ago and A Really, Really Long Time Ago) so luckily it's not too hard to figure out what they're on about.
    • To be more precise, one "rotation" is one "day" of their planet, 1 Drahn is equal to 4 million rotations and one Drahn is divided into two thousand Drahnasa. Some code examination reveals that the rotation of the Slylandro homeplanet is 14.2 earth hours which tells us that one Drahnasa is equal to 1180 earth days (a little over 3 years) and one Drahn is 2370000 earth days (roughly 6500 years).
  • The people of the Metroid universe use "cycles" for a span of time somewhere between a few months and about a year. Space Pirate logs often talk about projects being developed over the course of a few cycles, for example figuring out how to infuse their troops with Phazon, especially as it took multiple failed attempts. U'mos in Metroid Prime 2 is mentioned to be several centicycles old (technically it should be centocycles, but that's a different trope entirely). Might it be some based on other planet's year?
  • In Iji, The Tasen and Komato use "cycles", "pulsecycles", and "starturns", although how they correspond to human units of time is unknown. Starturns would presumably be a Komato year, but since we don't know how long it takes their planet to orbit, it doesn't help much.
    • According to Word of God, a Starturn equals a year (how long it takes Origin (i.e. Earth) to make a full orbit around its star), a Longturn equals a month (but it's unknown how many make up a Starturn), a Turn a day (how long it takes Origin to make one rotation around its axis), a Cycle an hour (unknown how many make up a Turn), a Shortcycle a minute (unknown how many make up a Cycle), and a pulsecycle a second (whatever the Komato pulse was when they came up with it).

     Web Comics  

  • In The Inexplicable Adventures of Bob!, the dragons and Nemesites measure time in "zarps." Since "half a zarp" seems to equal at least a short night's sleep, we can guess a full zarp is probably something between 12 and 16 hours. An author's comment when they first appear compares them to astroseconds, centons, and rels.
  • The trolls in Homestuck call years "sweeps", although the Alternian year is equal to around 2.16 Earth years.
  • In Escape from Terra most Belters use a decimalized calendar and time-keeping system designed by the Mars colonists. Particularly "centimes" (about 14.8 minutes, if my math is correct) and "decadays" (10 Martian days).
  • In Last Res0rt the galaxy has apparently adopted Swatch Internet Time

     Western Animation  

  • In Beast Wars: Transformers, 'cycles' are used for minute-like timespans. There are also "nano-kliks" (roughly a second), "decacycles," "megacycles," and "stellar cycles," which varied Depending on the Writer (megacycles at one point going from roughly an hour to, from context, roughly a year).
  • In Teenage Mutant Ninja Turtles, Donatello calculates a ratio of 1 Triceraton trigon to 10 minutes.
  • Transformers Animated uses this so much you really wish they'd just break down and convert the damn units. "Wait a cycle!" "I haven't done this in deca-cycles!" "I have bided my time for eighty mega-cycles..."
    • The original Transformers series had the infamous "astroseconds," "astrominutes," "astrolitres," "a Cybertronic mili-inch," etc. The first episode mentioned a unit of time called a "quartex," but it was never mentioned again.
  • In Reboot, the characters said things like "In a nano" or "Gimme a nano." Nano as nanosecond. The characters living in a computer, this actually makes sense.
  • My Little Pony: Friendship Is Magic uses "moons" as a "longer-than-a-week-but-shorter-than-a-year" measurement of time, and never specifies exactly how long a "moon" is. A common theory is that it's simply a pony-ism for "month" due to how its used and the association with lunar cycles. Thing is, in FIM the moon is controlled manually, and every other unit of time is unchanged, implying that it's not a standard month. According to the show's director, "it's a unit of time with no human equivalent." It tends to be used when the writers don't want to worry too much about the timeline.

     Real Life  

  • Historically, attempts to replace seven-day weeks with something else have failed. This has been attributed to, of all things, bearded men preferring to trim their facial hair on the same day each week: wait longer than seven days and it grows enough to get tangled; don't wait as long, and they're grooming themselves before there's much need to do so.
    • The Metric calendar failed in part because pretty much everyone (this was revolution-era France) still had to use the old calendar to track the Sundays. A calendar change also causes problems for holidays like Easter, the date of which is based on the interface between a seven-day week and the lunar cycle and moves every year. note 
  • When NASA scientists are talking in terms of subjective time on another planet, they use "sols" to cover a single rotationnote  of the planet, to keep the Earth measurements lined up with the clock. The Martian sol is 2.7% longer than an Earth day, so the difference is about 40 minutes a day. This can really add up over the months and years. Since all on-site equipment is solar powered, all scheduling is done according to the length of sols, and some team members have Martian time watches. Some particularly dedicated researchers end up having rather peculiar sleep schedules by Earth standards.
    • Martian time isn't that bad; the 24-hour-40-minute day will let you keep a reasonably stable sleep cycle that's consistent with the rhythms of the human body. Heaven help you if you were dealing with a planet that has 16-hour or 30-hour days, though...
    • Although continually sleeping 40 minutes later every day means that after about two-and-a-half weeks your AM/PM has completely flipped over and you're going to bed around noon and getting up in the late evening.
      • Another Men in Black joke:
        Zed: The twins keep us on Centaurian time, standard thirty-seven hour day. Give it a few months. You'll get used to it. Or you'll have a psychotic episode.
  • In 1969 the Swiss company Helbros brought out a "lunar watch" for the use of astronauts, which divides the lunation into 30 "lunes" of 24 "lunours". (Centilunours and decilunours for shorter periods.)
  • Various forms of decimal divisions of the day.
  • The Other Wiki lists several unusual time units, such as the 1.2096 second "microfortnight".
    • An in-joke in the Arch Linux community are kiloseconds.
    • Combining the above, note that a "millifortnight" comes out to 1,209.6 seconds, i.e., very close to 20 minutes, or a third of an hour.
  • The stereotype of Native Americans using the phrase "many moons ago", or similar, comes from some of them using a lunar calendar rather than a solar or lunisolar one ("moon" meaning "actual lunar month" as opposed to the abstraction called a "month" on a lunisolar calendar). Other cultures primarily speak in terms of seasons; Navajos, for example, are religiously forbidden to discuss certain religious subjects or do certain tasks (like weaving) except in winter, "the Season when Thunder Sleeps". Some cultures may have eight or six seasons instead of four, depending on the local climate or what the calendar is designed around (hunter-gatherers, for instance, may find the breeding seasons of deer more important than the planting seasons for grains).
  • There's a "bilisecond" (sic) in Microsoft .Net SQL API. Documentation describes it as 1 billionth of a second. Actually, it's 1/1000th of a millisecond, i.e. a microsecond. There were suggestions that whoever designed the API had no idea of metric prefixes and assumed "milli-" to be 1 millionth and "billi-" 1 billointh. Or maybe named the unit after Bill Gates. And misspelled it.