How do you measure time on a tide locked planet?

In summary, the planet is tide-locked and thus there is no day/night cycle, no seasons, and no way to measure time by the sun or the stars. Because the world is tide-locked, the sky is not readily visible and it's often raining. At ground level, there is a continuous stiff breeze coming from the dark side to the light side. To measure time, a plant or creature or primitive neolithic tribe would have to develop a system of their own.
  • #71
Vanadium 50 said:
Which is a criticism that can be lobbed at any unfavored idea.
You've got a tougher hill to climb than I do.
I need only demonstrate one path to plausibility.
You need to close off all paths in order to demonstrate implausibility.

And yes, in the creative world of sci-fi/fantasy stories, all things are possible until they shown to not be.

Meta: The circuitous road to the conjecture at the heart of this thread (a culture that doesn't rely standardized timekeeping) is the inspiration the OP might use to write a good story. You don't write a story explaining things already obvious. (Correction, you don't sell a story explaining things already obvious); you write a story to lead readers on a path they might not have taken on their own.I'll add one "last" note: I wonder if we all have different visions of this alien culture. If you and Russ are envisioning a culture with flying cars and skyscrapers, I can see your point; It would be pretty hard to get to that level of technology without accurate time-keeping. But that's only the last century or two of Earth society.

What about a culture that's equivalent to anything 2 centuries to 20 centuries behind us? Do you still think it is utterly implausible that a farming level society didn't ubiquitously use time-keeping as an aide? (Remember, their crops don't have to contend with day-night cycles, and seasonal changes are directly observable.) Time might be something for the scholars, but they might find it pointless in the fields and markets.
 
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  • #72
PeterDonis said:
No, it's not. Its period of rotation is about 58 days and its period of revolution about the Sun is about 88 days.

It used to be believed that Mercury was tidally locked to the Sun but that belief was found to be wrong when spacecraft were able to get close enough to Mercury to make detailed observations, sometime in the 1960s IIRC.

Mercury is as tidally locked as a planet in an elliptical orbit can be.
 
  • #73
Hornbein said:
Mercury is as tidally locked as a planet in an elliptical orbit can be.
No, it's not. As @Vanadium 50 said, the reason Mercury is stuck in the 3:2 tidal lock is that there is a potential energy barrier between it and the lowest energy 1:1 tidal lock.
 
  • #74
Some natural oscillatory behavior would be a natural timepiece. Perhaps near the terminator there would be an obvious sunset/sunrise due to the planet’s libration? Assumes the orbit is somewhat elliptical.
 
  • #75
DaveC426913 said:
What about a culture that's equivalent to anything 2 centuries to 20 centuries behind us? Do you still think it is utterly implausible that a farming level society didn't ubiquitously use time-keeping as an aide? (Remember, their crops don't have to contend with day-night cycles, and seasonal changes are directly observable.) Time might be something for the scholars, but they might find it pointless in the fields and markets.

Even without a growing cycle, farmers need to track how long it will take to plant or harvest an acre of vegetables, how long it takes them to mature, how long until the harvested produce spoils and cannot be sold, how long it takes to haul a wagonload to the town market, when the next market will be if there isn't a continual one, etc.
 
  • #76
Malapine said:
Even without a growing cycle, farmers need to track how long it will take to plant or harvest an acre of vegetables, how long it takes them to mature, how long until the harvested produce spoils and cannot be sold, how long it takes to haul a wagonload to the town market, when the next market will be if there isn't a continual one, etc.
Why?

Why track it? Why not just look at it?
The blorn stalks are 4 feet high. By the time we get the threshers out of storage, it'll be perfect for harvest. And market is always on the day the first leaves on the bloak trees fall.

Theyve had a billion years of evolution to get in tune with their world.
 
  • #77
Because the farmers that can track this stuff in their heads will have a competitive advantage, getting more acres harvested with less wasted motion, losing less produce to wiltrot, and always showing up at the marketplace a few decableems before you to stake out the best spot.
 
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  • #78
Malapine said:
Because the farmers that can track this stuff in their heads will have a competitive advantage, getting more acres harvested with less wasted motion, losing less produce to wiltrot, and always showing up at the marketplace a few decableems before you to stake out the best spot.
But you can't track a growing cycle in your head when the growing cycles are dependent on dozens of external variable factors. (That's true even here on Earth). The best only way to know if a crop is actually ready it is look at it - everthing else is a guess.It's always easy to tell a story that's already been told (the story of how Earth did things), and it's always easy - and lazy - to say "the way we do things is the best".

The point of writing a speculative fiction story is to show, step-by-step how a seemingly implausible thing can come-to-pass plausibly. (otherwise it would be one chapter instead of twenty).
 
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  • #79
Greg is ok with this thread, so I'm going to try to drop out, but I'll generalize my concern:
Vanadium 50 said:
Back to the topic at hand...

3. Might the aliens be too dumb to build a clock? I don't know. How dumb are they?
As a reader/watcher, I think I'd have a hard ...time... accepting a civilization that's too dumb to discover time but smart enough to become a civilization. Arguments about alternative means of...well....timing things are not really persuasive to me. The problem isn't whether they'd work, it's whether the beings could invent them without noticing they were inventing clocks. I'm not a sci fi writer so maybe someone could spin such a yarn and make it compelling, but so far I haven't seen one.
DaveC426913 said:
This is still Earth-centric thinking.
Well, it's Earthlings who need to be convinced to buy the book.
 
  • #80
russ_watters said:
As a reader/watcher, I think I'd have a hard ...time... accepting a civilization that's too dumb to discover time but smart enough to become a civilization.

You think "dumb" is the correct term here?

Isn't that what the Little-Endians said about cracking eggs on the Big End in Gulliver's Travels?

(The metaphor being "The only smart view is the one we hold. Everything else is dumb.")

russ_watters said:
Well, it's Earthlings who need to be convinced to buy the book.
Speculative fiction enthusiasts don't tend to buy books with the intention of reading about things already obvious.
 
  • #81
DaveC426913 said:
You think "dumb" is the correct term here?
I really do. Time is an obvious and inescapable aspect of how our universe functions. The examples given are, in my opinion, silly/not believable. It would be an exceptional blind-spot to not notice that what they were doing was measuring time.
DaveC426913 said:
Speculative fiction enthusiasts don't tend to buy books with the intention of reading about things already obvious.
I'm sure. Maybe I'm not in touch with just how far out there such readers are. Dunno. [shrug]. But I think it would have to involve a different universe or being without or beyond time to be believable. Like Q in Star Trek. At least he was kept vague enough that it was hard to ask questions (though oddly he spent a long...time...in our time). ...and then he died? What?

Also, not quite the same thing, but the time compression device for adding drama to movie action really, really annoys me. It pretty much ruined that one Star Wars movie for me where the Empire was destroying 10% of the rebel ships every second for like 10 minutes.
 
  • #82
russ_watters said:
It would be an exceptional blind-spot to not notice that what they were doing was measuring time.
I'm not saying they wouldn't notice; I'm saying it wouldn't be much use in their society. Sure, in egghead labs, but why would society care? An egg is cooked when you see it's cooked, not when some gadget on a lab bench finishes counting.

russ_watters said:
...it would have to involve a different universe or being without or beyond time
Argh! :mad: :mad: Reducto ad absurdum fallacy! Sometimes I wonder if you are being deliberately obtuse.I give up. You win. Alien civilizations will evolve in the same way - and come to all the exact same conclusions - as Earthlings. Star Trek is an accurate depiction; the galaxy is populated by races identical to Earthlings except for their foreheads. Spock's famous line is "Zero diversity, in exactly one combination." 🤔
 
  • #83
DaveC426913 said:
I'm not saying they wouldn't notice; I'm saying it wouldn't be much use in their society. Sure, in egghead labs, but why would society care? An egg is cooked when you see it's cooked, not when some gadget on a lab bench finishes counting.
1. No, you cannot tell when an egg is cooked by looking at the egg.

2. Even if you could, my complaint is that the idea that they don't even notice what's happening isn't credible. Unlike an egg, you can tell when a steak is cooked by poking it (if it is too soft, it isn't cooked). That doesn't mean people don't still time the cooking of their steaks.

You're saying maybe they wouldn't care, but then trying to provide an example where they might not notice. They'd care because they'd notice because it's a major aspect of how the universe works.

My incredulity here is keeping me coming back. The boiling egg is not a mystery. The idea of timing it without realizing you're timing it doesn't make sense. Even if you stand there watching and not realizing it's time that's passing, what do you do while you're waiting? Maybe you start singing a song? The egg boiling song you just wrote because you're bored? As it happens, the egg boiling song lasts as long as it takes to boil an egg. But only because you needed three verses because if you only sing two the egg ends up undercooked. There's no way an ancient civilization that understands little else about the universe doesn't understand that they are counting time when singing the egg boiling song.

I gave an example of studies of people in caves who are denied clocks. You might be able to write a story that uses that as background: people discovering/harnessing time without an external reference is a believable idea to me. Maybe they had chaotic sleep patterns until they discovered time and then that became an enabler of an organized society?

DaveC426913 said:
Argh! :mad: :mad: Reducto ad absurdum fallacy!
It's not a fallacy if the argument is actually absurd.
https://en.wikipedia.org/wiki/Reductio_ad_absurdum
Heck, we both agree on the validity of the example, don't we (the boiling egg)? Where's the absurdity besides in the actual idea?
DaveC426913 said:
Sometimes I wonder if you are being deliberately obtuse.
In what way? If your issue is that I can't see how one could do things without reference to time, what you might be missing is that my complaint isn't that they can't it's that they wouldn't even notice.

DaveC426913 said:
I give up. You win. Alien civilizations will evolve in the same way - and come to all the exact same conclusions - as Earthlings. Star Trek is an accurate depiction; the galaxy is populated by races identical to Earthlings except for their foreheads. Spock's famous line is "Zero diversity, in exactly one combination." 🤔
Humans did not invent the laws of the universe, we just discovered them. Yep, other species that are intelligent would, by definition, discover them as well.
 
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  • #84
DaveC426913 said:
I give up. You win. Alien civilizations will evolve in the same way - and come to all the exact same conclusions - as Earthlings. Star Trek is an accurate depiction; the galaxy is populated by races identical to Earthlings except for their foreheads. Spock's famous line is "Zero diversity, in exactly one combination." 🤔
Nobody won and nobody lost. The topic question seems to have been answered, but some members have not yet recognized. Somebody gave quick mention of a torsion balance? I gave mention of something like an hour-glass; a few other members made some constructive comments too.
 
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  • #85
russ_watters said:
I don't know for how many thousands of years humans have been boiling eggs, but in that time(!) we haven't come up with a better way than timing them.
Put the egg(s) in the pot of tapwater, turn the stove on, turn it off when the water starts boiling, and take the eggs out whenever you get around to it.

Asynchronous is a thing.
 
  • #86
DaveC426913 said:
What about a culture that's equivalent to anything 2 centuries to 20 centuries behind us? Do you still think it is utterly implausible that a farming level society didn't ubiquitously use time-keeping as an aide? (Remember, their crops don't have to contend with day-night cycles, and seasonal changes are directly observable.) Time might be something for the scholars, but they might find it pointless in the fields and markets.
Perhaps I lack imagination, but I fail to see how a civilization of self-aware individuals can arise without a notion of universal time. (Note that I am excluding here instinctual behavior based on internal rhythms and/or the external daily and seasonal cues available to animals on earth.) Lacking time, how can any set of two or more individuals converge to perform a coordinated group task like conferring, laboring, bartering, worshiping, fighting, etc.? Doesn't this necessitate the ability to dynamically recognize both a particular spatial location at which to gather and a particular point in time to do so? Is it plausible that a civilization could emerge strictly from perpetually uncoordinated, random meetings of individuals?
 
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  • #87
What are we even talking about? I was under the impression that we were discussing:

1.) A pre-bronze age civilization at best.
2.) A civilization that absolutely understands what time is, just doesn't have calendars, seasons, days, or anything else that would make an obvious way to track time.

How do they boil an egg?? The same frickin' way we did it for 10,000+ years before the invention of a suitable egg timer. Christ. Does no one realize we didn't have clocks for 99% of human history?

Anyways, this thread seems to have split between the original topic on how do you measure time on a tidelocked planet, and how would a society on such a planet develop in terms of their recognition and use of time in their day-to-day lives. The former is somewhat easy to answer. It just takes some thinking. The latter is very speculative no matter which side or stance you take. I think everyone would do well to remember that.
 
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  • #88
^^ wut he said
 

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