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Hi, I'm doing an add-on project that have many planetary systems in Andromeda galaxy, and in one of such systems there's an earth-like moon, very similar to Earth both in composition as in the shape of continents. But such "Earth 2" is bigger, have higher gravity, air pressure, slightly more CO2 and orbit a small gas giant, like Neptune, but maybe even smaller that migrated inward and captured planets that became moons. Here's the map of Washkn'Narax, the Earth 2. But one more thing, this map is still not complete because I'm trying to make as "realistic" as possible. The original size 16384x8192 pixels. Here, the resolution is 2048x1024.



In my point of view, it's very Earth-like. I want to know if someone like the texture and to give any suggetion or opinion. And one question. Do you think that earth-like planets with similar shape of continents ( earth-like continents )as above are common?

The texture seems to be great as well as the idea of making stars in another galaxy.Keep up the good work

There seems to be a lack of deserts. On Earth, there are two broad bands of deserts north and south of the equator because of convection-driven air circulation causing dry air to descend in the subtropics. Also, deserts would tend to form in the rain shadow of mountain ranges.

Is it rotating around its axis or tidally locked towards the jovian? On a tidally locked world the jovian side will likely be hotter than the outer side, causing convection that produces some kind of "subjovian" deserts in analogy with the subtropics. There will also be less Coriolis forces, making weather systems more variable (less rainshadow deserts?). If it is rotating on its own, then I would expect a more terrestrial banding.

Of course, on this planet there might not be any visible deserts because of some biological adaptations - those green areas may actually be very dry but covered with water-retaining plants that remain green despite growing in what is actually a desert. Or the atmosphere has a tendency to rain more.

Why would it be green? Plants on other worlds may be a different color than green.

The oceans are rather small. With such a low ratio of water to land, the chances are the world would have a drier climate. See the post above about deserts. The less moisture, the more deserts.

If the world is a moon orbiting a gas giant, and the length of the day is comparable to that of the Earth, and the world has existed long enough for life to colonise the land, then the world is going to be tidelocked to the planet. If the planet has an orbital period of 24 hours, it will be tidelocked very quickly, less than a thousand years. Life takes millions of years to evolve to the point where it can colonise the land. The only way it can have an Earthlike day length without tidelocking is if it orbited a long way from the planet, say greater than 5 million kilometres. That is not possible if the world is habitable because it would then be outside the Hill sphere (the realm of stable orbits for moons).

Finally, a technical note. Does your world have problems with polar pinch or have you overcome that? Your world lacks ice caps, although it does appear to have ice on mountains near the poles. I find polar ice caps to be a convenient way of eliminating polar pinch.

I am also interested to learn how you created such a beautiful map. It looks like you've used an image editor, a fractal map generator and something like Blue Marble for the texture of the land.

I'll make another map, because it seems that this map is somewhat "unrealistic". I erased such map in my project, but my new map will be almost the same as that one I showed, with continents somewhat similar to Earth. This time, the interior will have deserts, maybe I should put more water and I don't know if I'll put polar caps, since this world is somewhat hotter than Earth. The average temperature of such planet will be around 30°C and atmospheric pressure of about 7atm. With such air pressure, the temperature variation between poles and equator will be small, so no polar ice caps. It will have bigger deserts with more mountains, but at the same time the vegetation area will be even more green and fertile. The nightside texture will have city lights and a dark blue haze, as the nightside textures of our planet. I'll show soon a demonstration of my new and more "realistic" map.

This planet/moon orbit a gas giant with radius of about 36000km. The mass is low comparing to mass of Jupiter and Saturn, so the gas giant doesn't have a noticiable radiation belt. The density of Waskn'Narax is about the same as Earth, so having a density many times higher than the gas giant, this moon can orbit near the planet and it's orbit is elliptical, allowing the moon to have a slow rotation on it's axis. Think of Mercury. But because the moon orbit near the planet, the rotation axis speed is somewhat slower or maybe similar to Earth, depending on the value of elliptic orbit. Also because of the small distance relative to the gas giant, the tidal heating in the moon core is high, making this moon a very geologically active world, that have much more CO2 in the air than on Earth, and this also partially explain the high air pressure. But native life is very well adapted to it. The native plants love the high amount of CO2 and animals tolerate it as we tolerate our own air.

I use the Visible Earth high resolution textures, found here: http://visibleearth.nasa.gov/view_set.p ... oryID=2355 and I use Photoshop CS3.

Just a pointer from a fellow texture artist. Something you need to take into consideration is that an Earth like planet that is bigger and more massive than the Earth would have more convection cells formed around it. The Earth has three convection cells per hemisphere. Thats three in the north and three in the south. A slightly larger planet with a thicker atmosphere would certainly have 4 or possibly even 5 per hemisphere. This would totally change the way deserts would be laid out on a planet like this as well making the cloud patterns look different than they do on Earth. The clouds would be moving in narrower bands and look like the are between Earth clouds and a sub-jovian. Not the easiest thing to model or create in Celestia. I have toyed with doing something similar now that I know much more about how planet size, mass, and atmospheric density all play a part. If you look at some of the pictures of my Terraformed Mars texture in the Ultimate Terraformed Mars thread, you will see that I took into consideration how the dense atmosphere would work on a smaller planet like Mars. Of Course solar input has to also be taken into account and as has been mentioned the land to ocean ratio. It can all get a bit technical and sometimes it can take the fun out of just being creative, but if you keep to certain rules you can really create something outstanding.

Good luck and if you need any input, I can always give it.

Don. Edwards

Well I can`t do maps like that wish i could I like to put them in my Galactic Civilizations II Mod I`m working on so if there is any one wanting to make some maps for me....

I did like the MAP BTW!!

Galactic Civilizations doesn`t have all the ablilty that CELESTIA has but it does OK !! I just wanted differnt maps but still good looking ones!!!
Thanks
Nasty

But what is the formula you use to make textures considering convection cells, size, mass, and atmospheric density? Let's see, the air of my planet is 7atm pressure, is very humid, so few deserts because water is everywhere, I guess. I'm thinking to make a texture that is 50% land and 50% water, with some continents being somewhat similar to Earth continents both in shape and position. No polar caps, since the difference of temperatures between equator and poles is small due to thick air, and the average temperature is 30°C. But high mountains with ice will be present. Maybe I should put green and blue or black vegetation.

Maybe I was wrong,BUT a larger Earthlike planet wouldn?t be a panthalassic world with lots of water.Or this planet has only the atmosphere thicker?

As I said, the surface will be almost 50% water and 50% land with thicker air ( 7atm ) and somewhat higher gravity, but not so high. The system in whick this planet/moon is located is called Solaris. Solaris is a binary system with 2 near K5V stars and planets orbiting both stars. Such system is also very rich in heavy elements. Waskn'Narax is a moon that orbit a gas giant having radius between Uranus and Saturn. Until now, I made 5 big moons orbiting such gas giant, uncluding 2 more earth-like and 2 moon-like moons. Waskn'Narax is the biggest moon, and the 3 biggest earth-like moons orbit in the same orbit, period, but because of the different masses, the ellipctical orbits are different. Such system doesn't crash because all moons are in a stable orbit and one moon attract and repel each other in a uncommon balance.

Enio wrote:Waskn'Narax is the biggest moon, and the 3 biggest earth-like moons orbit in the same orbit, period, but because of the different masses, the ellipctical orbits are different. Such system doesn't crash because all moons are in a stable orbit and one moon attract and repel each other in a uncommon balance.

By what mechanism will the moons repel one another?

If you simulate these moons in a gravity simulator, you will find that multiple large moons in the same orbit are generally unstable, especially if other large moons also exist in nearby inner or outer orbits. I wouldn't want to live on an Earthlike planet with a moon-sized loose cannon of a moon orbiting nearby.

Take a look at the four large moons of Jupiter. They do not share orbits, but instead have settled down into orbits with resonances that are roughly 3 : 6 : 12 : 28 (that is, Io : Europa : Ganymede are in the ratio 1 : 2 : 4, and Ganymede: Callisto is in the ratio 3 : 7). These are stable.

Saturn has different resonances, largely governed by the influence of Titan. No other moon exists anywhere near Titan except for the small moon Hyperion, which is in a stable 3 : 4 resonance with Titan. Other satellites of Saturn have various resonances.

More on resonances here: Orbital resonance (Wikipedia)

You may find it useful to include resonances as well. It may mean you end up with fewer moons, but the end result will be more realistic.

I often do not include deserts on my terraformed worlds, because I expect that on an artificailly earth-like world, weather management systems would be sophisticated enough to distribute moisture around as required. Of course if the inhabitants like deserts that is a different story...

On the other hand a planet which is naturally earth-like would develop may different climate zones. Other factors that may effect the distribution of climate zone; one important effect on this world is the fact that it has much more land than Earth, so would probably have less moisture in the air. All other factors being equal, this world shoul be somewhat drier overall.

Another thing I have been adding recently to my worlds is shallow water in the coastal regions, which is lighter in colour than deep ocean seawater. Estuaries, bays, and shallow inland seas should have slightly lighter colour water than elsewhere.

I'm doing each continent of Waskn'Narax in separate files in high resolution. Each texture ( continent ) finished will be reduced in size. When all separated textures are finished, I'll put all them in a single and big 16k texture. Later, I'll reduce it to 8k or 4k texture, depending on the results.
Don't worry, the deserts in such moon will be larger, but keep in mind that the air pressure is 7atm, so more clouds and humidity. Also, the interior of continents have lakes, small seas and rivers, allowing vegetation near desert regions. So I'm thinking to not put a big Saara-like desert, but a least many small semi-deserts, specially between high montains, where wet air can't enter.

Enio,

I really like your texture, mostly because I am thinking about ways to create a similar believable texture for my own fictional planet, to be found at http://www.planetfuraha.org.

I am having difficulties on two fronts: the first is that I have never used computer paint programs much (perhaps because I was used to conventional painting methods). So I would appreciate it if you could elaborate just a bit more about how you painted your world. Did you cut and paste bits and pieces from a NASA map or Earth or similar? If so, do you have any specific tips to speed up my learning curve? Also, were you designing the texture from scratch, or do you base it on a height map?

The second difficulty is perhaps more something I should ask Don. Edwards. I have been reading through climatology material and found material about convection cells, the effects of large land masses, etc., but not enough to let me decide where to place what. When I look at Earth, I do recognise the 'desert belt', but it is hard to understand why some deserts are where they are, or why some regions are forested where others with a similar latitude show desert only. Any advise on where to situate deserts on Furaha would be most appreciated.

Oh ive seen furaha before, nice creation.

I myself do planet textures, and yes its a bit of cut and paste and merging, try to use the gimp which is free and a great tool, the maps can be based on altitude but youd habe to look for bits that look similar and then "cut and paste".

I used the high resolution textures from the Visible Earth site. The only thing I do is to brush selected small or big parts of the original to a smaller one. Later, if needed, I modify the colours of the resulted texture. But it takes lot of RAM to load such big images in Photoshop. Also, I spend a day or days to finish a big texture, specially that have 8192x4096 pixels.

In the case of 8k textures, I make the texture first in 16k. But I have problems to save 16k in DDS, so when I finish the texture, I resize it to 8k. In the case of 4k textures (less important planets/moons), I make it first in 8k, later I resize to 4k. I like to resize from bigger to smaller textures because the resulted texture appear to have more detail than before.

Now, here's my new Waskn'Narax texture:



It may look like more Earth than the last image, despite the new continents and vegetation colour. I decided to make the vegetation a green/blue mixture because this planet orbit a K and M star, so maybe a different pigment in plants will be needed. I also decided to add more continents relative to Earth because I think that so much water isn't needed to allow a rich and healthy biosphere. Earth could have half or one-third of it's ocean water, have much more land and still be healthy. Earth also have big dead zones in it's oceans, and such zones are desert.
The same apply to Wasn'Narax (except for the big dead zones). But this world is bigger than Earth, so even having more land than water, the amount of water is still about the same as in Earth. Both air pressure and gravity are higher, but it's not a problem for natives, because they are a bit smaller and stronger. There's more CO2 here than in Earth to compensate the bigger distance from the stars.
I put bigger deserts, one is Saara-like, in a continent similar to Africa. I don't like big dead zones because to me they are unuseful and space wastefulness. Although having so much land, the surface is full of florests and very dense jungles because in these regions there are lots of lakes and rivers, feeding the vegetation.

Is my new map better?

Welcome to Celestia, coen!
I am very impressed with your work on Furaha, and hope you find Celestia useful.
Since you have a very good map of Furaha already, you would probably find some difficulty using pieces of the Blue Marble texture to represent your world. Perhaps you could try using a good Earth texture as a basis for colouration in the various parts of the world, but it might be difficult fitting suitable parts together.

I use Imageforge and Gimp, although Gimp can be used for most purposes I find that Imageforge is often a bit easier to use.

Let me explain this map better. Antartida, in the south pole, is very fragmented. The big green island, to the right of North America-like region, is Atlantis. More to the right, is "Africa" ( having a huge Saara-like desert with some big oasis and a dense jungle to the south ) , "Europe", part of "Asia" and an extra continent ( a group of big islands ) to the right of "Africa". To the left of "America" is a huge continent, Lemuria. Part of Lemuria is a huge New Zealand and Australia. Up to Lemuria is a big green/yellow island, in the place of Japan. And more to the left of Lemuria is part of "Asia".
That's really an alternative version of Earth's map, an alternative blue marble. I need to know if someone liked that map or have an opinion so I can make that map even better, but keeping a resolution of 8192x4096 pixels.
One more thing I want to say here is that there's a lot of vegetation located in the same climate belt of deserts. But on Earth this also happens, even more on Waskn'Narax, that have even more stable climate caused by a thicker atmosphere. So vegetation and desert here depend more on the local conditions, like type of soil and geologic formation than on climate itself.

eburacum45 wrote:Welcome to Celestia, coen!
Perhaps you could try using a good Earth texture as a basis for colouration in the various parts of the world, but it might be difficult fitting suitable parts together.
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Thank you, Eburacum. I have started working on a texture map in Photoshop, based on what I see here as well as the advice by Enio and others (thanks!). I have decided where I should place the deserts (roughly along 30 degree latitude, near the middle of very big continents and with some rain shadow deserts thrown in; I do not know much about climatology but it will have to do...). It will be a medium size map (4096x2048), using cut, paste and blend techniques. At present that size seems big enough, and I definietly need more RAM before progressing to larger sizes.

I am thinking of using the height values in my elevation map afterwards to selectively alter colours using Matlab. In that way, I could for instance add snow depending on elevation as well as latitude, and make separate maps for winter in the Northern and Southern hemispheres.