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Podcreature
03-29-2014, 02:13 AM
Edit: I suppose I should have posted this in "Finished Maps" but I don't know if I want to leave the coastline looking like this.

Masking so many regions and doing canon research for my Pern project was very time consuming, so I decided to go ahead and finish a quick map for another project for the sake of testing my proposed work-flow. I'm not displeased, though I do welcome pointers on how I might have executed this better from a design/scientific angle. I'm probably going to take another crack at this type of planet in the future when I learn more.

Has anyone else seen a rendering of Gliese 581-G aside from the one or three images you can find on Google? Would be neat to see more art of these "eyeball" worlds.

In case some people are wondering what this is, Gliese 581-G is a theorized type of planet, earthlike in size, orbiting a red-dwarf star in the "goldilocks zone" (close enough to have liquid water.) The problem is that when a satellite orbits the cooler stars close enough to have liquid water, they become fixed in orbit, always facing one direction.

Revolutions around the sun at this short distance would only take a little over 30 days! That's one short year... Anyway, this always facing one direction is the reason for some interesting geography. Scientists originally speculated that they must look like eyeballs. Not much going on tidally or anything, but if there were currents, and warm weather fronts, we'd (apparently) have an un-frozen area that looked like a lobster not an eye, lol. But I thought an eye-world was cooler.

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Original PS base, made by pasting Earth, Mars and other space DEM data together.
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A bit of Wilbur editing.

I colored it in photoshop by using adjustment layers and gradient maps of various combinations. I also used Curves to select certain low and high areas from my base heightmap. I think the normal map I did needs to be inverted. Not sure.

Diamond
03-29-2014, 02:43 PM
That is a really cool idea, and nicely executed.

Slylok
03-30-2014, 12:42 AM
I like this alot! I dont get how it would look lobster like instead of eyeball like. Does the planet spin perpendicularly to its sun?

Podcreature
04-01-2014, 02:22 PM
Thanks Slylok, Diamond. :D I don't get the lobster shape either, actually... I understand winds, currents and convection distributing heat, but the shape would be dependent on the planet's topology too, and certainly on rotation. If the planet doesn't turn how can there be winds and currents? I think that's what you're getting at, and I agree. It was college students, I think, not astronomers who came up with that particular idea, but they are probably on the right track to use a 3D climate simulator. There's an article that talks about it here Full atmosphere-ocean model of a rotationally locked exoplanet | Ars Technica (http://arstechnica.com/science/2013/12/full-atmosphere-ocean-model-of-a-rotationally-locked-exoplanet/) but it seems eyeball worlds are still accepted in the eye-shape overall, and that makes more sense. Clouds wouldn't swirl around, they'd just steam up around water and reflect the sun's rays, but also trap heat underneath that radiated from the central desert. The clouds would freeze, and deposit snow around the edge of the ocean. This would create a huge glacial range that's constantly encroaching on the sea, but melting at the same time. New research shows that being so close to the star produces a beneficial greenhouse effect, because intense UV radiation splits oxygen atoms and creates a thicker ozone layer around the planet as well, meaning the dark side of the planet doesn't quite get cold enough to freeze the atmosphere, and lock it away. This could happen to the water, but the ice-ring that forms from the clouds loitering around the sea creates an additional moisture barrier. All theory of course... Need more time and more ideas. :)

Anyway, here's the map on a globe in ZBrush. Might need some tweaking still.

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Slylok
04-01-2014, 02:49 PM
This also means that its always daytime here. I'd think the life on the planet would evolve alot differently than it does here. id imagine rings of different species of plants and animals around the steady temperatures and climates. How would intelligent beings here measure time? How did their skill of navigation evolve without being able to see stars in a night's sky? What does the food chain look like in the different areas? This is really fun to think about.

the concept looks great. do you plan on taking it any further? does it have any moons?

Edit: Actually since the sun is always in one place they would just need one star to navigate.

Podcreature
04-01-2014, 03:44 PM
Those are helpful questions Slylok! Haha, ohright, the sun! It would be very interesting indeed, to think that if there's a highly evolved species on this planet, stars would be an uncommon sight to them, until they started sending up satellites or traveling to the twilight areas on their planet. Colonizing the far-side would be much like building a moon-base, so it certainly wouldn't be possible until they'd reached some kind of industrial era.

Good point about the moon... tidal flux would be a good way to stimulate an ocean current and nudge primitive sea critters onto land. That might also break up the clouds a bit so it's not such an even blanket in the coastal areas. I think a moon would be necessary for a lot of reasons. It would also make the sky a little more interesting, because as you pointed out, it doesn't really change much.

Most ecosystems are dependent on the sun, so it would probably be much the same here. Something one might consider is how foggy it must be by the water most of the time. Again, that's why the tide might be handy, to stir up the sea and clouds. Bring some rain inland.

Despite the red dwarf star being dimmer, being so close and having it be day all the time would still be a great environment for photosynthesis, I would assume. I thought about the native life having chloroplasts in their cells instead of mitochondria, or a combination of similar creatures, so that animal life is somewhat sun-dependent. I pictured a reptilian-looking race, with scales that keep in water, to be the resident sentients.

Time-measurement is an interesting question. Their year would only be about two months long. These revolutions would be the crux of any calendar.

As for what I plan to do with this, it's just a sci-fi comic project I'm planning to put out mostly for exercise on another site. I just get so engrossed looking for explanations and end up spending a lot of time on settings lol. So I do plan to develop it a little more at least... The next step is to actually pick an existing red dwarf that's main sequence but old enough not to put out too many flares. Eye-earths have enemic magnetospheres, since they don't rotate. This makes them vulnerable to solar wind that could blow off their atmosphere over billions of years. I actually imagine that life from another planet could have "recently" seeded this world however, so that might explain the presence of a lot of water.

Thanks for the thoughtful feedback. :)

Raptori
04-01-2014, 03:59 PM
Edit: Actually since the sun is always in one place they would just need one star to navigate.

That comment reminded me of an interesting piece of information I read in Jared Diamond's book Collapse which could be relevant to this world. He spent a lot of time on an island in the Pacific called Tikopia (http://en.wikipedia.org/wiki/Tikopia) which is particularly isolated, with next to no contact with the outside world even today. The island they live on is so small that they can see the ocean from almost any spot, and that they're all intimately familiar with every square meter of the place. They denote direction in relation to the ocean - for example in one instance that Diamond witnessed himself, one islander told another that they had some food on the oceanward side of their face!

If the sun is completely stationary in the sky, the inhabitants would be likely to behave in a similar way to this I think!

Lingon
04-01-2014, 04:11 PM
This looks neat! It's very nicely done and I like the idea. Though I have to say, it's rather unlikely that the landmass would be that round and perfectly centered on the dayside ;)
I don't know if this is interesting, but I started a thread about a similar setting about a month ago. I haven't had time to finish the map yet, and it deals with a somewhat different situation where the tidal lock was sudden on an already inhabited, normally rotating world, but there are some links and discussion there that might be fun anyway (or not)! Here it is, if you want to take a look:
http://www.cartographersguild.com/regional-world-mapping/26201-tidally-locked-planet.html

Podcreature
04-01-2014, 04:51 PM
That comment reminded me of an interesting piece of information I read in Jared Diamond's book Collapse which could be relevant to this world. He spent a lot of time on an island in the Pacific called Tikopia (http://en.wikipedia.org/wiki/Tikopia) which is particularly isolated, with next to no contact with the outside world even today. The island they live on is so small that they can see the ocean from almost any spot, and that they're all intimately familiar with every square meter of the place. They denote direction in relation to the ocean - for example in one instance that Diamond witnessed himself, one islander told another that they had some food on the oceanward side of their face!

If the sun is completely stationary in the sky, the inhabitants would be likely to behave in a similar way to this I think!

Thanks for that input Raptori! This can be very useful, after all it would be a waste of good science fiction not to formulate a specific way that natives navigate on a planet that lacks day/night cycles. It's especially cool when we can use real world facts as a template. Side note; creatures native to a world like this would probably be very disoriented on a planet with a sun that seems to move. It might even make them sick.


This looks neat! It's very nicely done and I like the idea. Though I have to say, it's rather unlikely that the landmass would be that round and perfectly centered on the dayside ;)
I don't know if this is interesting, but I started a thread about a similar setting about a month ago. I haven't had time to finish the map yet, and it deals with a somewhat different situation where the tidal lock was sudden on an already inhabited, normally rotating world, but there are some links and discussion there that might be fun anyway (or not)! Here it is, if you want to take a look:
http://www.cartographersguild.com/regional-world-mapping/26201-tidally-locked-planet.html

Thanks. :) I look forward to reading more thoughts and ideas in that thread. I'm excited to see that others hare hypothesizing about these kinds of worlds!

I agree that tectonics are the primary way continents are formed. To decide how to lay out my land masses, for an earth-like planet, I had to look at Earth. We also know that water does have a huge impact on how land masses form, though it may not be that obvious. Where water is constantly deposited, the land will erode. Over hundreds of millions of years, we'd see rain dumping on the outer edges of the warm zone. Land in the center will be continually dryer. Oceans would form around the perimeter, and expand because water has weight. The crust would become thinner there, creating fault-lines, pushing the land toward the middle. Planets try to stay in a spherical shape. Where there are glaciers, the buildup of freezing water, the ground depresses. Where there is rain, and glacial melt, there is erosion and pooling. So in the cooler zones, that are not quite frozen, over time, we'd see oceans congregate there, erosion and ice breaking up the land. So the formation of ice on the back of the planet, we'd have the trapping of a lot of water, but not all. And under the ice, there's probably an original shape of land masses, with the erosion on the warm side creating a cookie-cutout of whatever land was there. As clouds form around the sea, and encroach on the outer ring of the world, they deposit snow, creating huge ice-ranges. As they expand, they slide and crumble into the sea, but the tall range is growing at the rate that it is deteriorating, maintaining a height that is a barrier to the clouds, trapping liquid water in the warm zone. The extra thick ozone is the only thing that prevents the atmosphere from freezing on the dark side of the planet. Anyway, that's how land masses would most certainly be shaped by the congregation of water. In the confined space that isn't glacier, fault lines would appear where the crust is shallower, depressed by the sea, so the coastline would have more volcanoes.

Of course I would need a computer simulation to be sure of how any of that would really find balance and I am not saying a world like yours isn't possible. That might be a scenario where the oceans remained liquid or slush. Possible with enough greenhouse gas. Some simulations reveal that tidally locked planets have a big hurricane around the band, dumping rain on the far side constantly, and I imagine that's what my own world was like in the first millions/billions of years, before glaciers built up, or the planet drifted a little further back in the habitable zone.

Slylok
04-01-2014, 06:20 PM
Time-measurement is an interesting question. Their year would only be about two months long. These revolutions would be the crux of any calendar.

true, but how would they know that they have made a revolution? There wouldn't be any seasons or animals migrating or anything they could discern that would indicate a completed orbit around the star. Maybe the moon/moons are the answer to this as well. A Solar eclipse would be pretty interesting for people that know no darkness.


That comment reminded me of an interesting piece of information I read in Jared Diamond's book Collapse which could be relevant to this world. He spent a lot of time on an island in the Pacific called Tikopia which is particularly isolated, with next to no contact with the outside world even today. The island they live on is so small that they can see the ocean from almost any spot, and that they're all intimately familiar with every square meter of the place. They denote direction in relation to the ocean - for example in one instance that Diamond witnessed himself, one islander told another that they had some food on the oceanward side of their face!

If the sun is completely stationary in the sky, the inhabitants would be likely to behave in a similar way to this I think!

Good point! I would imagine where ever you were the sun would be "north".

Also I think they could use the rings of vegetation as terrain reference for how far away from the sea they are.

Podcreature
04-01-2014, 07:02 PM
true, but how would they know that they have made a revolution? There wouldn't be any seasons or animals migrating or anything they could discern that would indicate a completed orbit around the star. Maybe the moon/moons are the answer to this as well. A Solar eclipse would be pretty interesting for people that know no darkness.



Good point! I would imagine where ever you were the sun would be "north".

Also I think they could use the rings of vegetation as terrain reference for how far away from the sea they are.

Ah, yeah, I keep thinking in terms of an advanced civilization... but how indeed would a less technical people set up a calendar that included the planet's interaction with the sun if there's no change in climate to mark it, and what would be the point? The moon(s), then, would become the most important element to track time. Two moons might help in making that calendar more complex. We might have a calendar that truly omits the entire aspect of years. I was hoping that the orbit might be slightly eccentric, just enough to cause a bit of seasonal change, but they'd be so rapid... A week-by-week rotation almost. The temperatures would be unified, but maybe not entirely. The sun being "north" is very reasonable... I forget the science behind a compass... Just out of curiosity, what would a real compass do on such a planet? It has no poles on which it turns, at least, it turns soooo slowly, the magnetosphere is very weak.

Raptori
04-02-2014, 06:54 AM
Compasses point to the magnetic poles, whose position is arbitrary. On our planet it's fairly close to the north pole, but every so often it switches in polarity.

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So their magnets would point to their planet's magnetic pole, and assuming that would stay roughly consistent they'd effectively have two points of reference to work with when navigating. Pretty sure that'd make navigation a lot easier than it is on Earth. I'm not sure if it actually would stay in the same place though...

Multiple moons sounds like it'd be good for the calendar, though it'd be worth using a simulator to work out where they could go without knocking each other out of orbit while still being visible from the planet's surface :)

Podcreature
04-03-2014, 03:26 PM
I suppose that a tidally locked planet does have poles... they turn at the same speed that they rotate around their star, so rotating every 55 days or so produces a very weak magnetosphere, and the problem is compounded by a cooler core, which would further weaken it. thankfully scientists have become optimistic that these planets would develop thicker ozones from the very radiation that would strip them of their atmospheres. This thicker ozone means Earth-like radiation levels on the planet's surface and shields the atmosphere from blowing away. Back on subject though, I guess even if the magnetosphere barely reached above the atmosphere, it would be enough for a compass to detect. Using the planet's poles and the placement of it's sun in tandem with the moons means navigating would actually be pretty straightforward.

And just to throw it out there, there's always sky color as reference. It would be whitish, greenish, blue at the apex, and the further away you go, the more orange/red the sky would become. These sky color zones might be perceived as entirely different "worlds" by primitive people. Governed by different gods or spiritual entities. After all, there would be marked differences in temperature and humidity from one to the next.

I figure the moons would have learned how to get along before recent billions of years... the red dwarf I finally settled on is already 8 billion years old, meaning the tidally locked planet is also most likely very old. I'd assume that they are the product of debris clouds either from the solar system's formation or stuff swept up later over time, and it would have been before life evolved on the planet because as you point out, there could have been serious collisions at that time. Each moon would represent debris that was swept up in it's path, cleaning up it's zone as it formed.

Podcreature
04-03-2014, 03:43 PM
Sorry to double-post but I just had a thought for Slylok. One thing that actually might reveal the 55 day revolutionary cycle would be planetary wobble. The sun might wiggle in the sky slightly. Ancient astronomers would have likely found this interesting, if they thought to track shadows, which I'm sure someone would notice the "wiggling" and try it.

Podcreature
04-03-2014, 04:29 PM
Just going to follow up with another image. This is the solar-system info I'm sticking into the chart for my species. The text is just there for reference, not the final/actual data. I'm having trouble deciding on names for the planet, moons and star. Pretty sure humans there are calling it "Terra Ocula" (redundant, I know, that's humans for you) ...but the natives would have given it a different name. Not sure what I'll do for background color or effects yet. May just keep gray since it's not distracting.

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sangi39
04-04-2014, 01:53 AM
Just a quick post and run, have to leave for work in the next few minutes:

Earth's magnetic field - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Earth's_magnetic_field#Physical_origin)

Podcreature
04-05-2014, 02:24 AM
Thanks Sangi39! That link also got me looking at the moon's magnetic field more... since it's also a tidally locked rocky planet-like thing with a small molten core. According to your Wiki link, it's the movement of liquid under the planet's crust that creates the magnetic poles. Supporting what scientists say about tidally locked worlds. The core would spin slower, it would in turn be cooler than Earth's. But it would remain to some extent. Bigger worlds apparently have stronger magnetospheres, but I wonder how that scales up proportionally. I guess not only are there weak poles but less tectonic and volcanic activity on this planet.

JefBT
04-08-2014, 10:11 PM
Isn't a moon unlikely to happen in this kind of planet?

The planet itself may not have a strong eletromagnetic field to maintain a moon. Maybe some asteroid.

Not only the sun, but the planet's temperature may be it's "north". I mean, hot places, like the center of the ring, would be the "north", and the cold places may be the "south".

The world may be next to some medieval versions, like the flat pizza world, with the "end of the world" as waterfalls to "nothing". In this planet, the hot and the frozen places might be the "end of the world".

Raptori
04-09-2014, 07:42 AM
Moons are held in place by gravity not magnetism, so there'd be no problems with having moons :)

JefBT
04-09-2014, 08:33 AM
I forgot about gravity. I was just thinking that it could be like Mercury from our solar system, that does not have a moon.

Thank you Raptori.

Meshon
04-09-2014, 11:33 AM
I forgot about gravity.

So many times I've wanted to do that. :)

Azelor
04-09-2014, 12:02 PM
I'm not sure that your planet can have a satellite because it is tide locked. Think about it, the gravity pull form the star is strong enough to stop the rotation of the planet. What would happen to the satellite in that case?

Raptori
04-09-2014, 01:09 PM
Thinking about it you're right. The moon would have to be far closer to the planet for it to orbit the planet rather than the sun, so a smaller moon moving at extremely high speed and relatively low altitude orbit would be more plausible... o.O

JefBT
04-09-2014, 01:17 PM
Also, orbiting at high speed on low altitude may impact the planet's rotation as well, after some time. Or at least the water level may change very often.

Azelor
04-09-2014, 03:24 PM
Thinking about it you're right. The moon would have to be far closer to the planet for it to orbit the planet rather than the sun, so a smaller moon moving at extremely high speed and relatively low altitude orbit would be more plausible... o.O

I don't think so but Universal sandbox indicate otherwise...

acrsome
04-09-2014, 04:44 PM
Yes, a moon would be unlikely. Unless it were a recently captured vagrant.

With a giant ball of fusing gas in a predictable location in the sky, I doubt that the locals would care much about magnetic compasses. It would be pretty damned easy to fix your latitude, just by measuring the height of the sun above the horizon. As always, fixing longitude would be more of a challenge. In fact, my mind boggles on a way to do so, even with accurate clocks. Perhaps with very accurate stellar measurements, but that could only work near the ice zone where you can see the stars. The stars also wouldn't wheel around the pole star (if there is one) as quickly as they do on Earth- instead, one rotation would take one year.

More intersting is how they would define direction. North/South/East/West makes little sense. Perhaps they'd use a polar system instead? Clockwise, Widdershins, Axial, and Radial? (With Axial defined as "towards the spot where the sun is directly over head," and Radial as the opposite.)

Also, there's really no reason to expect the hot side to be all land, is there? There'd be no ice given the model you're using, true. But there might be a sea crossing the hotside pole. Land might run right up to the ice sheet in some spots. Etc. Because, yes, the planet would be pulled into a bit of an egg shape, but that tidal force is acting on the water too, so you can model it as a flat surface. High points are high, low points are low (and full of water, which is rapidly evaporating at the hotside pole).

Podcreature
04-16-2014, 06:47 AM
I'm not sure that your planet can have a satellite because it is tide locked. Think about it, the gravity pull form the star is strong enough to stop the rotation of the planet. What would happen to the satellite in that case?

Really great feedback guys, thanks for sharing all your thoughts. It's truly helped my system become not only more realistic but more detailed. :)

Actually tidally locked planets rotate, they just rotate at the same rate that they make a revolution. That is why this planet does have a North Pole, just like our moon does. Where it is just depends on axial tilt. Orbit is indeed possible, though I'm sure it would be eccentric. I hadn't considered it too big of a problem... The real problem, I realized, after these theories got me doing more research, is that unless the moon was close enough in mass by a factor of 10 it would either fall into the planet or the sun at some point depending on which orbit was faster (which is in agreement with Raptori's theory except that larger moons actually are more sustainable.) The real problem here is just that a very big moon would probably cause the objects to become tidally locked to one another - a great idea for a different planet project, but alters this one too much.

I figured some kind of collision would have been the reason for the moons, but if they'd be falling into the planet eventually, I'd rather scrap them, however, it seems interesting that two similarly sized objects can be tidally locked to each-other and orbit a sun... I -could- go with my collision idea and say that once there were two worlds orbiting one another, which is a scenario that would give life an earlier chance to get started, too (wider habitable zone from day/night.) Let's say a disaster broke up the sister planet, creating a few moons, either destined to someday coalesce into a large enough object to hold orbit, or eventually fall into the sun. The recent-ness is really not a big issue, since in astrological terms "recent" can give or take hundreds of millions of years. My ancient sentient race is only a tenth of that age. Life could have survived such a bombardment and still be very diverse at present, (Die-offs actually promote evolution, by opening new niches for more and more complex organisms to fill.)

But I digress, if most of the debris was propelled at a trajectory that sent the largest chunks of the sister planet into the sun, leaving smaller bits to shower our host or coalesce back into the biggest remaining chunk of the sister, then it might work out for life. The moon might still be large enough to orbit for a good while if, like Raptori says, it's close enough.

This would cause some strange things to happen, but I think they might be beneficial. The tides would be very aggressive and stir up the sea a bit, good and bad... There might even be a noticeable change in gravity depending on where the moon is at, just fun... I assume the planet would stay locked to the sun but it would wobble distinctly. This would actually help create more dynamic weather, and keep hot spots from being too extreme - the desert in the center might not actually cook flesh off bones. (Otherwise, my world doesn't have a big enough liquid sea to have a lot of ocean current and distribute heat.) The moon would have to be just the right size, though I'm confident that size exists, whether I figure it out or not. In conclusion, it doesn't really matter if the moon will stay in orbit forever, because neither will our own, after all.

Podcreature
04-16-2014, 08:27 AM
Also, there's really no reason to expect the hot side to be all land, is there? There'd be no ice given the model you're using, true. But there might be a sea crossing the hotside pole. Land might run right up to the ice sheet in some spots. Etc. Because, yes, the planet would be pulled into a bit of an egg shape, but that tidal force is acting on the water too, so you can model it as a flat surface. High points are high, low points are low (and full of water, which is rapidly evaporating at the hotside pole).

Thanks for the thoughts on navigation. Ideas are welcome, as I have yet to settle on something that will work for future maps... should I work up the nerve to make one that's detailed, and I'm hesitantly tempted.

To answer your question, I wouldn't say I "expected" it to be all land when I made it that way. I guess it's just fun to embrace coincidences. Not to mention, I do prefer my land organisms to have more real-estate to compete over. I decided that this world looks this way specifically because I just imagined this large continent on the face, and erosion along the glacial melt zones made a cookie cutout of the warm region. But here's some reasons it might look the way it does... aside from coincidence/preference: Most of the ocean is frozen on the back side of the planet, keeping sea-levels low on the face. Rain falls frequently along the "green band" and erodes the earth there. When glaciers melt water pools in the depressions they made. So it's a cookie-cutter concept, basically, and water is the cutter.

Nexis
04-18-2014, 10:32 PM
HI.

I was reading this thread and had a thought. Depending, of course, on the planet having a small or large elliptical orbit. This may cause sun watchers to see the sun "Beat like a heart" in a year. This may have more theological implications than navigational.

The other idea comes from Eratosthenes. The scholar who measured the circumference of the world by measuring the path of the sun by studying the shadow of a stick. If you place a stick directly under the sun at 90 degrees from the ground it would cast no shadow. Moving away from that stick and place another, it would cast a shadow directly away from the center under the sun. Do this in a circle and farther away you can have a very accurate navigation instrument and mapping. Carrying a "Sun Compass" will tell you how far away you are from the "Sun-ward" center of the world and the direction of the shadow will always point in that direction. That will create a compass if you standardize the height of the stick you can measure the distance away you are from "Sun-ward" by measuring the length of the shadow. Say If you want to reach the city of Randar you must travel North- East of sun-ward for seven shadow lengths. North south east and west generally being directions away from the Sun Center of the world.

Podcreature
04-25-2014, 03:31 AM
I actually was thinking of having an elliptical orbit for the sake of temperature flux basically seasons, but they'd be on a 2 month cycle, lol. May be worth it, but the "pulsing" sun would be really neat.

And that is the best example of navigation on a planet like this I've heard yet... or at least for a very specific navigation tool that incorporates the planet's tide-locked status. The length of the shadow would definitely be the key there. Would have to maek sure it's level though. Maybe you could wear it on your wrist like a watch, and it could be a little globe, or flattish orb, water filled, so the plate inside stays level, and in the center of the plate is a little needle or something. This wouldn't have to be very big at all. With the direction of the sun and the length of the shadow, you could know exactly where you are at any time! With this and a map you'd be set.

UPDATE: Well I did a little mooore research and apparently the orbit of our planet is eccentric, but slight flux in distance from our sun has very little to do with our seasons. I kindof already knew it had something to do with Axial tilt but didn't know which played more influence. (Wasn't as interested in this stuff when I was in school, lol) So... I'm thinking this planet will have some kind of axial tilt, because seasons will be very helpful for life, but it will cause the sun to change position notably. So to navigate with such a thing as a sun-dial, you'd need to know the season, too I guess. Currents and dynamic weather can actually increase the size of the green band considerably... I wonder if an eccentric or elliptical orbit really would cause noticeable change in sun's appearance.

In conclusion, this planet will probably have an equator, a minuscule elliptical orbit (since it was probably two planets orbiting each-other and one was lost, disrupting a perfect circle slightly) and most likely an axial tilt, since scientists think the collision that produced our moon was the cause of Earth's. There are magnetic poles but I wonder if the sun will still be useful in mapping too if it moved in the sky a bit. Might need a map for each of the 55 days in a year.

And here's the finished chart, I'm basically done with this for now... until I decide to update the planet's topology, and create a real map with political and climate information. (The moon isn't that small, it's not orthographic view, it's how big it actually looks from the planet.)

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sangi39
04-26-2014, 10:19 AM
You could also use a vertically-hanging weight and then measure the angle of the sun in relation to that vertical line to determine latitude. While the sun-shadow compass realised on a standardised length of the stick to make accurate calculations, this method relies on accurate and equal divisions of a circle, so they both have some drawbacks. Actually, thinking about it, does the sun-shadow compass need to be a standardised length? If you measure the length of the shadow, then the ratio of that length and the length of the stick would end up equal for any length stick at the same latitude. As Podcreature points out, however, the only problem is making sure it's exactly vertical to the ground, but several methods could be used to fix that issue.

As for determining longitude, I think your best best would probably be to use a magnetic compass. While magnetic north might not line up with axial north, the position of magnetic north is relatively stable over the space of centuries.

If you take the measurement of the suns position in the sky in relation to magnetic north, then you should be able to determine longitude (if the sun is directly behind you as you point the compass toward north, then you're north, while the sun being directly ahead of you would put you in the south while the sun being directly above would put you at the magnetic equator. If you're on the equator, but then as you move east the sun should the sun should be directly to your left while it should be directly to your right as you move west. Positions in the north west would then have the sun be behind you and to the right and so on and so on. You should, then be able to work out your exact position from there using either the sun-show compass or the weight-angle compass. I think :P

Nexis
04-26-2014, 02:08 PM
You could also use a vertically-hanging weight and then measure the angle of the sun in relation to that vertical line to determine latitude. While the sun-shadow compass realised on a standardised length of the stick to make accurate calculations, this method relies on accurate and equal divisions of a circle, so they both have some drawbacks. Actually, thinking about it, does the sun-shadow compass need to be a standardised length? If you measure the length of the shadow, then the ratio of that length and the length of the stick would end up equal for any length stick at the same latitude. As Podcreature points out, however, the only problem is making sure it's exactly vertical to the ground, but several methods could be used to fix that issue.

As for determining longitude, I think your best best would probably be to use a magnetic compass. While magnetic north might not line up with axial north, the position of magnetic north is relatively stable over the space of centuries.

If you take the measurement of the suns position in the sky in relation to magnetic north, then you should be able to determine longitude (if the sun is directly behind you as you point the compass toward north, then you're north, while the sun being directly ahead of you would put you in the south while the sun being directly above would put you at the magnetic equator. If you're on the equator, but then as you move east the sun should the sun should be directly to your left while it should be directly to your right as you move west. Positions in the north west would then have the sun be behind you and to the right and so on and so on. You should, then be able to work out your exact position from there using either the sun-show compass or the weight-angle compass. I think :P

Yes. Determining the compass bearing so it lines up correctly was bugging me. I had the same thought about the magnetic pole but I like your idea of the hanging weight on a line as a more accurate vertical tool.

Podcreature
05-03-2014, 07:27 PM
I've really enjoyed all the brainstorming about navigation. :) It'll also be very helpful later, I'll have to credit you guys somehow if I use your sun-dial tool ideas, lol.

So, jumping into my update... I did a little more research on the "lobster" shape and it -does- make sense... when we see a world without day or night we automatically think it doesn't turn, but as I figured out and mentioned earlier in reference to poles and such, that it does. That rotation, however slow, does create a current. Apparently we could find tide-locked worlds that are either eyeball shaped or lobster shaped, so I guess it works that mine is a bit of an oval... either way, I figure that where it's at in the goldilock's zone, means that where it's dark, it's basically snowy. But where the warm air drags across the planet it's a habitably snowy cold until you get further around the planet.

In light of this understanding I have reworked my map, and I've taken time to think about the ecology and oxygen producing bacteria that don't photosynthesize and came up with some new and unique colors for the seas and shores in the twilight zones.

There's still stuff to fix, like inconsistent borders, the wrong plant growth in certain elevations and zones, and I will need to painsteakingly hand-draw the rivers since I didn't figure out how to generate a river mask thing in Wilbur before diving into this... eeehhh...



Edit: I welcome suggestions for styles and themes that go along with functionality as a map for a story or RPG. ..As in I'm trying to decide what do with it at this point.

AlexSchacher
05-04-2014, 12:04 AM
the only problem is making sure it's exactly vertical to the ground, but several methods could be used to fix that issue.

I know this is just a TV show, but in Vikings they do this by letting the sun-compass float in a bucket of water so that its always level to the plane of gravity. (I think)

Podcreature
05-04-2014, 01:46 AM
I know this is just a TV show, but in Vikings they do this by letting the sun-compass float in a bucket of water so that its always level to the plane of gravity. (I think)

That's exactly what I was saying like, five or something posts back, lol... not about Vikings, but a sun dial on a plate that's sitting on water. I wonder if there's a way it could be made to fit on a person's wrist if the craftsmanship was advanced enough. Like in a glass bauble or disk. It would need to be oil in that case so it wouldn't evaporate and fog the glass.

Nexis
05-04-2014, 02:40 PM
That's exactly what I was saying like, five or something posts back, lol... not about Vikings, but a sun dial on a plate that's sitting on water. I wonder if there's a way it could be made to fit on a person's wrist if the craftsmanship was advanced enough. Like in a glass bauble or disk. It would need to be oil in that case so it wouldn't evaporate and fog the glass.

Hmmm. How about using mercury? Far more stable than water. Maybe the plate could be magnetic and point to North to mark your bearings, then read the shadow length.
I think a wrist version would be too small for serious navigation. You would need a much larger plate to get an accurate distance reading.
For that I would think loose gimbals on a tripod would keep the plate level while a floating compass on mercury will give you a bearing to adjust the plate to read the shadow. The plate would be engraved as accurately as the technology of the people will allow.
It would be large, maybe 1 foot across to be accurate. This would be used by explorers, merchants and the military. Casual travelers usually would stay on known paths and not go very far from home so the use of a personal compass would be more of a rich man's toy or jewelry.

Edit: Wait a min! I keep forgetting about spirit levels! You don't need to float it. Just place a bubble in a fluid in the center of the compass and you can adjust it till it becomes level.

Podcreature
05-05-2014, 09:49 AM
Hmmm. How about using mercury? Far more stable than water. Maybe the plate could be magnetic and point to North to mark your bearings, then read the shadow length.
I think a wrist version would be too small for serious navigation. You would need a much larger plate to get an accurate distance reading.


I'm in agreement with all of that! I'm sure natives figured out how to mine mercury as early as humans ever did. I totally agree with the need for larger tools for precise navigating, was already thinking that to myself too... Some trips might not need as much so varying levels of size and quality would likely be seen. For any version that did use a glass bauble and an air bubble, would water scatter light and dim or affect the shadow? I guess that could be calculated for... Though convenient versions might still use a bed of oil or mercury, just because trying to hold it level yourself could be a little annoying, since it could be a big deal if you're off even a little bit.