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Lingon
02-14-2014, 08:57 AM
I've been thinking about a world… I've actually had it in mind for a long time, and I made an early draft for a map about a year ago, but for no special reason I decided to pick it up again, scratch everything and only keep the most fundamental part of the setting. It's a world that suddenly, without any clear reason, became tidally locked to its star. I have more details, some characters and the start of some kind of plot, but they are very fuzzy… Anyway, I'd like to write a novel about it, but I'm in the middle of another writing project, so I think I'll make a map first :)

Here's a rough draft. Black is coastlines, dark grey is mountain ridges, light grey is rivers, the orange blob is the dayside and the blue blob is the nightside. I sketched the shapes by hand and then traced them in illustrator, because G.Projector does weird things to pencil lines… The first one is in the Robinson projection to give an idea what the world looks like. The second is the one I think I'll continue working with, in Equirectangular Oblique to make the inhabitable twilight band around the planet a straight line. I cropped away the extremely distorted (and rather irrelevant, frozen and burnt) top and bottom.
6139961400

What do you think about the Oblique one, is it a good choice? It gives a very unusual height:width ratio, which I rather like… but it makes it very hard to grasp the shape of the continent. As always I'll paint the map by hand, so when I've decided on a projection I'll print it and trace it on watercolor paper. That's why the mountains and rivers are so simple, and why I'll remove the color blobs first – must save printer ink…

Maraxus_
02-14-2014, 09:46 AM
I think the right map makes more sense. On the left, there is this outer rim of the map, that is actually very interesting to the setting and should not be split up, while on the right: Who needs details about the wastelands in the dayzone or the endless ice in the nightzone?

Two things that come into my mind: The day zone will be frozen over, if this has the base parameters like earth. Look at the north pole, it does no melt even in it's summer days, when the sun constantly shines on it at a low angle. When the sun does not shine at all, there should definitly be ice.

The dominant wind direction is easy: Air rises on the hot side and thus falls on the cold side and near the surface there will be a constant flow of air from night to day, thus the habitable rind will probably be a good bit towards the sunny side. Less "Land of the perpetual dawn" and more "Land of the perpetual 9 o'clock forenoon" :D

Jalyha
02-14-2014, 10:38 AM
I like the choice of projection.

It IS unusual, but not unheard of, (I referenced a Japanese map, somewhere around here, that has near the same dimensions) If this is the only inhabitable part of your planet, I doubt they would map the rest?

And although you're right, you can't make out the shape of the continent this way (it does take away some of the subtle intricacy) you have to start *somewhere* and not all maps are going to show the whole continent anyway... especially if it is different countries..

I would turn it more north-south, though, just for clarity (unless I have mistaken? you turned it?)

I'd say do this map, and when you've got it finished, and got the time, lol, you can map out the rest of the world. :)


And I'm eager to see where you pull in those influences :P

Pixie
02-14-2014, 02:49 PM
This will generate a nice map/world. And I can imagine it will only allow for life on a marginal N-S strip, so the map projection fits perfectly. I'm curious to see where this goes.



The dominant wind direction is easy: Air rises on the hot side and thus falls on the cold side and near the surface there will be a constant flow of air from night to day, thus the habitable rind will probably be a good bit towards the sunny side. Less "Land of the perpetual dawn" and more "Land of the perpetual 9 o'clock forenoon" :D

... adding to Maraxus ...
Sea currents will be mighty and sea level will vary a lot in the planet, I reckon. Continuous heat on the lit side will not only evaporate a lot of water but also generate water bodies expansion on the sunny side. This, in turn, will generate a gravity fueled movement towards the dark side on all the oceans. On the other hand, very strong Dark->Lit winds will push the water surface forcing currents that bring icebergs into the light. Where these two contrary movements meet you will get perpetual rain and ubiquitous thunderstorms.
Furthermore, since the planet is rotating very slowly, Coriolis force might be negligible so the currents (sea or air) will be mainly dependent on the mountains/coast design and the region where they mix will tend to be the same and very well defined all the time.

(This is all guesswork, grounded, but guesswork...)

Lingon
02-14-2014, 03:28 PM
Thanks for the comments!
@Maraxus: I haven't done any calculations, but I don't think you're completely right on the science bits. The dayside won't be frozen, it gets constant direct sunlight. The poles on Earth are not comparable because of the angle they receive light from. With the winds, the atmosphere on the night side would thicken because of the cold, pulling air from the day side, I think… I agree with you about the projection though :)

@Jalyha: Yup, good points :) Yeah, we'll see where I can get those influences in… (Jalyha and I were talking about African fantasy settings on PM)

@Pixie: Thanks! The weather will probably be pretty crazy, yes! I will do some research on this.

Here's a small update… I've just added some more detail, mostly. Considering the winds, does the rivers seem ok like this?
61409

Jalyha
02-14-2014, 03:34 PM
Ummm... idk. I'm having a lot of trouble imagining the winds, so it makes it hard :P

I think the rivers look good though ^.^

Maraxus_
02-14-2014, 05:24 PM
Lingon: I'm pretty sure, the light side very close to the rim would have ice. What I wanted to say with the north pole comparison is, that: The north pole in summer has very long days of very low standing sun. That the sun goes down for a few hours (except the very middle of summer some few days) evens out the fact, that at midday it's a good bit higher than the horizon (light hits at a blunter angle thus more heat per area). This way I think the situation exactly at the rim is comparable to earth's poles. (It would be better, if earth had no axial tilt but it has to do. I guess you can imagine, that the poles would not suddenly melt if the earth would turn a bit to rotate in the solar system disk.)

Now, how far day-wards the frost-zone would go is a different question. And of course, if your planet has a warmer average temperature (more greenhouse effect, stronger sun, anything,...), than obviously the rim can be ice free or the border of ice.

Yes, the dark side would be one huge high pressure zone and the light side one huge low pressure zone.


Pixie: I think you are overestimating the gravity fueled movement. I think the water would flow towards the day-side, too, to replace the water that evaporates there.
Let's see, the hottest places on earth get around 55°C warm on their all-time hottest days. Now, if the sun would not be directly overhead at the beginning and end of summer, this would probably be even warmer. Maybe 70°C? Much more important of course is, that the sun never goes down and never shines from a low angle, thus the light energy per area should be 4 times as high per time than on the hottest day. Since hot bodies give away energy faster than not so hot once, this does not fourfold the temperature but it should still be a huge impact easily increasing the temperature to 150 or 200°C. Water boils and evaporates (As you move away from the point where the sun is directly overhead, this should fall quite quickly, so the costal lines seam possible to me, though I'd expect the innermost shores in the day zone to be boiling hot.)

And I definitly agree with the bad weather. The hot side evaporates a lot of water, hot air can carry more water than cold air, thus as the air cools down on its way towards the dark side, their will be lots of rain. And since this rain falls from a rather high altitute, some of that will probably turn to snow and hail

Jalyha
02-14-2014, 05:37 PM
The differences between the light side of a tidal locked planet and the earth's poles are many.

First and foremost, the poles are getting light all day for 1/2 the year. The second half is dark, and cold. The light side of *this* planet is *always* light, and warmed by the sun.

The poles receive (even in their summer) indirect sunlight, the light side of this planet receives direct sunlight.

The ice already at the poles from prior circumstances (Ice Age, anyone?) has a cooling effect as well. That *keeps* the poles cool, even when they would normally warm under the light. This planet doesn't seem to have had the same unique series of events, and has, therefore, no huge ice masses in the area you're comparing to the polar caps.

I'd imagine that there would be no ice at all, well into the "dark" side of the planet, especially with such a huge landmass, which also tends to warm things up.

And there would be high and low pressure zones on EACH side, because sunlight/heat is not the only thing that affects pressure.

@ Pixie: Sounded dead-on from what little I did bother to check. :)

Lingon
02-15-2014, 05:21 AM
Thanks for your thoughtful comments. I've read some discussions on the topic on science forums now, and though I still haven't made any calculations (and probably won't – I don't want to know exact values of things as they would likely limit more than help), I think it would roughly be like this:

1. Winds start moving as if the dayside is the equator and the nightside is a pole, i.e. cold surface winds towards the dayside, hot winds higher up towards the nightside. Nightside gets an ice cap, dayside gets hot rising oceans and a heavy cloud cover. The habitable zone is quite large, stretching both into day and night, but probably more into day. The poles still have their ice caps.

2. As the atmosphere condenses on the nightside, winds shift to moving only "nightwards". More and more water from the dayside gets frozen into the night cap, creating huge beaches of salt (should look cool on the map…!). Water beneath the night cap is pulled by the sun's gravity towards the dayside, creating some sort of interrupted cycle where all water slowly gets deposited on the ice. The habitable zone shrinks both ways, but because of the winds that carry lots of water, the land towards the dayside is kept from drying out, making the zone remain slightly more into the sun. The old polar caps probably melt towards the dayside, giving even more water flow into the habitable zone.

3. The magnetic field gradually weakens because of the slowed rotation and the solar wind blows even more of the atmosphere towards the nightside, where it either leaves the planet or gets trapped in the indent made by the weight of the night cap pushing the bedrock downwards. The seas are completely vaporized on the dayside, the rivers from the melting edges of the nightcap boil away in the desert. The habitable zone is very very thin and the air is hardly breathable.

Or something like that :P I have no idea how long each "step" would last, they would surely overlap a lot, and it's only based on forum discussions and Wikipedia articles compared with my intuition… But does it seem to make sense, sort of? And any idea how long it'd take to get to stage 2, where I think the map and eventually the story should be set?

Jalyha
02-15-2014, 10:17 AM
A looooong time :P ?


It does make sense, but most of this is all going to be based on no more than discussion, scientific theories, conjecture and gut instinct, since no one has ever actually watched it happen.

but it makes sense.

I've no idea how long thaat would take, though :/

I'll read around and see if I can find something :P

Azelor
02-15-2014, 10:47 AM
I suppose that the habitable zone would be really thin. Only the places that are at the dawn/dusk or near the middle zone would be livable. Otherwise temperature change as you move toward the poles ( center of day/night regions) to a point where water will boil or freeze instantly. Difference in temperature between the extreme would probably be over 500 degree Celsius.

I don't know if life could develop on such a planet even with the presence of a zone that as temperatures around 10-30 degree Celsius. And what about the winds, the pressure zones are always the same so the wind direction is always the same? Since the differences in temperature are extreme compared to earth, winds would be extreme too? No water in the daylight and it's all frozen in the night side. That mean few evaporation and even less rain no matter where you are.

But still I suppose life could survive with some help of the god Lingon. Or perhaps these people live in caves under the surface ?

Jalyha
02-15-2014, 11:19 AM
Omg I want to live with the Cavepeople.


Wouldn't the size of the planet affect how much of the land was actually live-able?

Kokor
02-15-2014, 11:47 AM
There are a number of science fiction games that can describe worlds in scientifically accurate terms. GURPS Space or related suppliments was extensively researched and can give a resonably believable results.

The 'world generation' takes into account luminosity of the sun, albedo of the planet, density of the atmosphere, percentage of ocean coverage, etc. If the sun is warm enough any ice blowing out from the night side would melt. That would provide at least some liquid water, maybe enough for extensive oceans.

You map is nice, and I agree the projection centered on the 'twilight band' makes more sense, if you think the inhabitants are biased towards the areas they live. You would have to do an overlay of an ice-cap across the night side areas.

Azelor
02-15-2014, 11:49 AM
I was thinking something like this : Yaodong - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Yaodong)

Diamond
02-15-2014, 02:46 PM
If you want some additional reference on how another person went about representing a tidally-locked planet, this is one of the best I've ever seen: Throl: non-rotating planet by IainFluff on deviantART (http://iainfluff.deviantart.com/art/Throl-non-rotating-planet-272946035)

Jalyha
02-15-2014, 04:44 PM
Now that's gorgeous!

Lingon
02-15-2014, 04:46 PM
A looooong time :P ?


It does make sense, but most of this is all going to be based on no more than discussion, scientific theories, conjecture and gut instinct, since no one has ever actually watched it happen.

but it makes sense.

I've no idea how long thaat would take, though :/

I'll read around and see if I can find something :P
Thanks, good to hear you think it sounds reasonable. Yup, it's complete speculation, but that's what makes it fun! I'm not sure it'd take that very long actually… Now I am really only guessing, but I'm thinking of savannas on Earth. Some of them only get rain once per year, and a year later, just before the next rain, they are almost desert-like. And then imagine that the sun is shining literally 24/7… It'd probably take a few generations, but, like, on a geological time scale… I think it'd be fast. Pure guesswork though, and I'll continue with the research. I appreciate that you'll read around too!


I suppose that the habitable zone would be really thin. Only the places that are at the dawn/dusk or near the middle zone would be livable. Otherwise temperature change as you move toward the poles ( center of day/night regions) to a point where water will boil or freeze instantly. Difference in temperature between the extreme would probably be over 500 degree Celsius.

I don't know if life could develop on such a planet even with the presence of a zone that as temperatures around 10-30 degree Celsius. And what about the winds, the pressure zones are always the same so the wind direction is always the same? Since the differences in temperature are extreme compared to earth, winds would be extreme too? No water in the daylight and it's all frozen in the night side. That mean few evaporation and even less rain no matter where you are.

But still I suppose life could survive with some help of the god Lingon. Or perhaps these people live in caves under the surface ?
Good thoughts! Thanks! I'm not actually concerned about life development in these conditions, as the tidal locking was sudden. Before that, the planet was very Earth-like. I think the inhabitants were at a dieselpunk-ish tech level, by the way :)


Omg I want to live with the Cavepeople.


Wouldn't the size of the planet affect how much of the land was actually live-able?
It sure would! Considering the size of the supercontinent, a lot of it was probably desert even before the locking. The size of the planet would affect the size of that desert. But I was thinking of an Earth-like size, for simplicity… I'm starting to feel I'm gonna need all simplicity I can get :D


There are a number of science fiction games that can describe worlds in scientifically accurate terms. GURPS Space or related suppliments was extensively researched and can give a resonably believable results.

The 'world generation' takes into account luminosity of the sun, albedo of the planet, density of the atmosphere, percentage of ocean coverage, etc. If the sun is warm enough any ice blowing out from the night side would melt. That would provide at least some liquid water, maybe enough for extensive oceans.

You map is nice, and I agree the projection centered on the 'twilight band' makes more sense, if you think the inhabitants are biased towards the areas they live. You would have to do an overlay of an ice-cap across the night side areas.
Thank you. Yeah, I think they would be biased like that :) I'm not sure if you mean anything specific with the overlay? I will show the ice cap somehow, probably by just not painting anything there :)


If you want some additional reference on how another person went about representing a tidally-locked planet, this is one of the best I've ever seen: Throl: non-rotating planet by IainFluff on deviantART (http://iainfluff.deviantart.com/art/Throl-non-rotating-planet-272946035)
Well you're about to get a new favorite! :D Kidding, that's a cool map. I'm honestly not a big fan of the style he chose, but I will take a good look at it and read through the text to see how he solved some of the issues. Thanks for for the link, D!

Jalyha
02-15-2014, 05:04 PM
Good thoughts! Thanks! I'm not actually concerned about life development in these conditions, as the tidal locking was sudden. Before that, the planet was very Earth-like. I think the inhabitants were at a dieselpunk-ish tech level, by the way :)


Well, now I'm concerned.

Not sure that something like, say, the Earth suddenly stopping its' rotation, and I'm picturing flooding, tsunamis, earthquakes, entire cities (states? Countries?) collapsing in on themselves...




I don't think there'd be anything simple about it o.O How do your people survive? D:

Azelor
02-15-2014, 05:14 PM
it's a sudden stop... well if it's less than a week, it would still be liveable. Expect a rapid change in temperatures. But possible

Lingon
02-16-2014, 03:03 AM
@Jalyha: Never said it would be simple, did I? :P Of course, a big part of the population died during the locking. The rest escaped to the inhabitable zone, which is terribly over-populated and can't produce food for everyone. But I think the twilight band would be pretty fertile land, with lots of meltwater coming from the glacier and around-the-clock sunshine at a low angle, so it might not be such a super-huge problem, at least for those with money.

@Azelor: Do you mean if the stop took a week, or if it's been a week since the stop? Would you mind linking to your source or posting the calculations for that? I'd like to see the parameters that gave the result, because it's not working with what I had in mind and even though I'm willing to ignore some things, I like to know what I'm ignoring :) (And preferably not ignore it at all.)

Here's probably the last update before I start the hand painted version, a mock-up of the composition. It also has the twilight band slightly towards the dayside, which seems the more likely way if my reasoning with wet winds keeping the soil and air moist is correct.
61464

Azelor
02-16-2014, 10:42 AM
I understood that the stop was relatively sudden and I supposed it took less than a day to completely stop the planet...

Temperature variation would be around 10-50 Celsius per day I expect. If Amazonia was on the dark-side for example, the temperatures would go from 30 degree to less than zero in less than 24h. We both live in Nordic countries where extreme weather occurs from time to time. A 10-20 degree change is nothing exceptional in less than 24h but think about what would happen if it was -20 degree everyday. And if it was -50 degree or more...

I looked at the numbers and some place are worst than others. In the desert, the difference between day and night can be quite high (around 30 according to wikipedia: Diurnal temperature variation - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Diurnal_temperature_variation))
But it's possible to have higher variations. I know the Chinook is just a wind but it help to get an idea of the maximum variation in a day : Chinook wind - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Chinook_wind)



I like you map. I do think the band in the middle is too large but after all, this is art and not science.

Jalyha
02-16-2014, 10:55 AM
That looks awesome.

(And I love your working title :P )

I think the week thing... I mean, if you stop something that's moving (just tried it with an old baby toy with a spinning ball on top) suddenly, it jerks.

If you put your finger on something to stop it slowly (like one of those pinwheel toys) it stops in a series of jerks.

No big deal if what you're messing with is a toy... what's a little shaking?

But picture that planet grinding to a stop... you're shaking the world.

So each time you shake it, buildings will fall, or tidal waves or tsunamis or... whatever.

Well we can survive a disaster. And another right after... well, lots of dead, but people are resourceful, right? And then another and another and another and another ...


yeah after too many of those in one short time frame, might be no one would survive. I can see how "suddenly" might have to be reeeeaaaally sudden.

I can also see how, if the stop was really gradual, like hundreds of years, it would be survivable then too...


Of course this is all me "supposing" and playing with baby toys, so...

xotoxi
02-16-2014, 11:05 AM
I don't think this situation would be compatible with life. First of all, there would be no atmosphere or water because there would be very little gravity. Secondly, there would be only a very thin zone where plant life could live and photosynthesize...so there would be not much oxygen.

But it would be a perfect planet for sand monsters and ice monster to live, and engage in intense battles in the twilight zone.

Lingon
02-16-2014, 12:18 PM
Azelor: Ah, that's true! Temperatures can shift very quickly. So, referring to my 3-step process, you're saying that the steps would be reached within a few days of each other? That does make sense. There are some factors that would counter it though. The heating would make a massive cloud cover over the dayside, which would reflect a lot of sunlight and slow that down a bit. And the strong winds would carry a lot of heat to the nightside. Salt water also has a lower freezing point than 0 C, but that's a minor thing here. Anyway, you are probably right that everything would happen much quicker than I figured. Hm… I guess my characters will just have to come up with a solution quicker, too. >:)

Jalyha: Haha, thanks, I'm happy with the title too! I felt so creative, you know, I got this flow, the words just poured out into geniality and… Uh… Anyway. You've got a point about the jerking. When I said sudden, I was thinking of natural causes for tidal locking, and that it would be sudden compared to that. I was actually imagining a year or so, of days slowly getting longer. First, none would notice, but then clocks don't match up with the sun anymore, and everyone winds their clocks back at the same time… thinking of some kind of prologue here :P But it might have to be quicker, as this kind of stopping would eventually give extremely long days and nights and no twilight zone to escape into, and probably kill everything on the planet. So maybe… a month? I really want the slowing day-night cycle, for dramatic effect…!

Xotoxi: Not sure what you mean about no gravity? Gravity has nothing to do with rotation, only with mass. The Moon is tidally locked to Earth, which doesn't make a difference for its gravity, for example. You have an excellent point about the oxygen production though. Not only would the atmosphere get thinner because it's sucked to the nightside, it's also become less and less breathable. Oooh, so many problems for my inhabitants… I love it :D Not planning to make this story about monster battles, but I guess some interesting creatures would evolve if the planet somehow remained livable for long enough!

Kokor
02-19-2014, 02:49 PM
I'm not sure if you mean anything specific with the overlay? I will show the ice cap somehow, probably by just not painting anything there :)

Not to tell you how to do your own map, but I think you could do an interesting ice cap if you look at what you have already (mountain ranges and seas) and compare that to Antarctica, for example. Considering how much of your world would be covered in ice it might be more interesting to give that blank area a little detail.

Lingon
02-19-2014, 04:32 PM
Kokor, please do tell me how to do my map! ;) I appreciate all feedback and suggestions. You're absolutely right, a large ice cap on varied terrain could look very interesting with the right treatment. I'll do my best :)

I just got a couple of commissions that I need to focus on for a week or two, then I'll begin with the hand painted version of this one :)

Azelor
02-19-2014, 08:05 PM
The heating will be much more dramatic at the center of the daylight zone. Near the twilight zone, it would be slower and some places would have a stable, livable temperature.

xotoxi
02-19-2014, 11:45 PM
Xotoxi: Not sure what you mean about no gravity? Gravity has nothing to do with rotation, only with mass. The Moon is tidally locked to Earth, which doesn't make a difference for its gravity, for example. You have an excellent point about the oxygen production though. Not only would the atmosphere get thinner because it's sucked to the nightside, it's also become less and less breathable. Oooh, so many problems for my inhabitants… I love it :D Not planning to make this story about monster battles, but I guess some interesting creatures would evolve if the planet somehow remained livable for long enough!

Good point about the gravity. I was thinking that the spinning was needed for gravity, but of course I was wrong.

This is an interesting article I found about tidally locked planets.

Dark Side of the Earth: What would happen if our planet became tidally locked? (http://io9.com/5980667/dark-side-of-the-earth-what-would-happen-if-our-planet-became-tidally-locked)