# Mapmaking Discussion & Philosophy (WIP/Critique) > Sci-fi/Modern Mapping >  The Sun's hood

## Azélor

I played Stellaris because of the latest patch and of course, it gave me the urge to make a space map.
The problem is that I did not have any specific goal.
I wanted to make a space map showing the stars and their planets.
But then I wanted to have realistic planet placement and decided to use the Sun neighbourhood as a starting point.
I think I chose the most practical way to display the information in 2D. Most space-maps don't show the planets and stars like this. 
Stellar objects closer to the main star appear right above. Objects further are placed progressively following a clockwise rotation.

Problem 2: Most planets have not been found yet and we have very little information on the others. 
For example: the Sun has 8 planets (sorry Pluto) but the average is closer to 1 or 2. A lot are missing. 
So I did guess the types of some planets.
It is an optimistic map yet still realistic. 

Problem 3: where to send the colony ship?
Consider that Helios 2 (fastest object humanity ever made) at max speed would take around 20 000 years to reach Proxima Centauri and that a manned spacecraft would take even longer...
It would be easier to terraform Mars and even Venus. 



Unrelated
I also did a few planets for fun:
(the top one is a brown dwarf)
It is inspired by Kurzgesagt but I tried to give it a different look.



Btw, I ended my Stellaris game before the end because it always drags on to a crawl.
I played a pacifist religious turtle-like democratic theocracy... in a federation with a zealous pacifist

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## elboe

Very nice way to depict the distances to the stars. Looks good. It's a difficult task to represent the 3D empty nature of the local space around our star system.

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## Arkidemis

You did a great job! Very easy to read and doesn't feel cluttered in the slightest.

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## Ilanthar

Interesting start, Azélor!

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## Azélor

> Very nice way to depict the distances to the stars. Looks good. It's a difficult task to represent the 3D empty nature of the local space around our star system.


I mostly recreated a style that I've seen at several places. i think the original version of the map has been auto-generated with a software.
Also, Ilanthar, I consider this map finished

I'm still thinking about making another star chart. The biggest problem is always how to represent the third dimension.

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## Azélor

I started working on a stellar system generator. those I've found on the web are not really good. 
Most seems to use random numbers or have an obscure method.  For example, one had as much chances of generating an class M star as an F star, which is extremely inaccurate. 
I think I managed to do something not too bad by using as much real world data as possible. 

*GOAL: generate stars (single and multi star systems) and their planets with some basic information*

So far, I have the stellar class distribution.
I have the probability of how many stars there is for each system. 
I can generate each star independently or in groups. 
Then, figuring out how many planets there are in each system. We don't know how many planets there are so I've made my own distribution with an average of 6 planets per systems. 

In the last part, I assign different planets to different star categories. 
 Flare stars, about half of the M stars (or 38% of the total) have different planets because the flares tend to strip the atmosphere of the planets and cause massive radiations. Lastly, like others M star, these stars are cold/dim, in order to be warm enough, planets need to be quite close and will be tidal locked in many cases. 
White dwarfs are another poor candidate for good planets. These stars are dying and have gone through massive changes (novae). Whatever lived there before is dead but life can begin anew after the star has "stabilized". The problem is that these star emit massive radiations and planets need to be so close to them (in order to be warm enough) that they are almost tidal locked, which is a big problem for life. 
The most massive stars (O,B A) die too young to have planet able to support life. They are also less likely to have planets I think, planets don't have enough time to form before the star dies.
The remaining stars with the most potential are F,G,K and M. Although I might further split M stars for those that are the dimmest : planets located in the habitable zone are tidal locked. 

As I said, each kind of star have different planets. I made some classification and i would like some thoughts about it. 

Those I have at the moment:


Barren: no atmosphere. example Mercury (well Mercury does have some kind of atmosphere but it's marginal) 

Ice: covered by a thick layer of ice and snow, might have a thin atmosphere. They are unlikely to have any by scifi depict them with breathable atmosphere. Hoth. 

Desert: dry, tends to be hot. Mars, Tatooine. 

*Earth like planets*: maybe the categories are redundant. They are all habitable but have different temperatures/moisture level. 

Tundra: milder than the ice planet, can support an atmosphere and complex lifeforms without requiring terraforming. Earth during the glacial age  

Arid: More humid than the desert planet and can easily support an atmosphere with life. This is what a terraformed Mars could look like. 

Temperate: This is Earth. Also include the ocean planet type. The only difference is that they have few landmasses. 

Jungle: warm and humid. it is possible to have the whole planet as a rainforest with the right atmospheric composition. mezozoic Earth, Dagobah 


Toxic: the planet used to be an Earthlike planet but gradually became closer to hell. Rising temperature made the oceans boil and to the point where water vapour was expelled from the atmosphere by the rising pressure. These planets have dense and hot atmosphere. Venus. 

Superearth. Planets similar to Earth except they are a lot bigger, have higher gravity, tend to have a denser atmosphere. In my definition, these planets are not gas dwarf, and are limited to planets that could support life. 

Gas giant: I included all the gas planet together. My main concern is toward habitability so i don't have an incentive to differentiate these kind of planets. These planets are usually heavier than superearths and have a thick gaseous envelope. 

Brown dwarf: technically, these are failed stars but there could be so many that I prefer to classify them as large planets. These are usually a few times the mass of gas giants. Unlike real stars, they are not massive enough to fuse atoms. They still produce heat but they are extremely cold even compared to the average M stars. They can have their own systems, called rogue stars, but we don't have a lot of info on them because they are too dim to see. 

About the planet distribution: since we know very little on exoplanets, this is going to be a lot of guesses. Some things are more obvious than other: I've set 85% of all planets to be barren with flare stars. I guess a planet can be dry or covered in ice but without an atmosphere, it's not much different from a barren planet. that's why I'm wondering if some of the categories are redundant or just not well defined.

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## Azélor

My generator is mostly done now. 

It can generate star systems with multiple stars and planets in a relatively realistic fashion.
I could not find how to order stars and planets in a certain order after they have been generated without messing things up.
For example, I would like to take the generated stars in a new column and order them by mass to find the main star of the system. So if I have a system with a G star and a M star, the G star is considered the main star.

But that is not mandatory, it 's pretty obvious which star is the most massive in most cases. Giant old stars would be more problematic to classify mass-wise but they are very rare. 
I've generated around 50 so far and haven't encountered any issues. 

It would be cool if i could add subsystems (planet orbiting around a star that is orbiting around another star) but there is so little data on exoplanets that I might has well do whatever I want. 

I've decided to include LMTY (whatever) stars known as Brown Dwarf since they are apparently not that common. About 1/6 of all stars, assuming they are considered to be stars. They are categorized as YTL.

I don't know how multiple star systems are supposed to be arranged. I assume that if 2 stars are of a similar mas, they will orbit one around the other (a common barycenter). But it gets weird if you have three stars of similar mass, since the system should be unstable. It is possible to have up to 7 or 8 stars in the same system. There is actually one of such system IRL. Multiple star systems are common but it's unlikely to generate anything above 4 stars.

You can test it here. It's the third tab. Press F9 to generate new systems. 
System generator.zip

As I mentioned, I made planets pretty common, possibly an optimistic vision but not too much. 
Yet, planets able to support life are not very common.
With more planet per systems, habitable planets became more likely. If you triple the number of planets, you triple the possibility to have at least one habitable planet per system. 
I adjusted the number down. Many stars can't generate habitable planets at all. 
 Most have thin atmosphere, liquid/solid ones or none at all.

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## Azélor

I think I've completed my system generator. It can now generate 25  random systems simultaneously, with stars, planets and population. 
Most of the numbers can be modified without too much difficulty. 
After some tests, I have a population sample of 1850 systems. 

The average population per system is 0,87 billions but the median population is 0,5. 
It is common for a system or two to control over 80% of the population (out of a group of 25 systems).

I might use it in a near future project.
Feel free to test and comment. 

Here's what the generated systems look like:


The file is here, the results are in the results tab, press F9 to generate new systems. 
System generator x25.zip

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## Azélor

I did a style test here. Celestial object are properly scaled. Distances are not.
Depending on the propose of the map (which is still unclear), it might not be a good idea. 

star map test of test.zip

It is a pdf in a zip file because the site does not recognize the pdf format. 
The yellow star in the background is really massive. This version was cropped but on the full map, it take more than 50% of the area. It would say it is a mid sized hypergiant star. Eta Carinae is 50% larger. 
My star systems are generated randomly and the chances to generate such star is ridiculously low. 
The actual systems are in the bottom left.

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## Ilanthar

Yup  :Very Happy: , that yellow star is pretty much overwhelming the rest...
I personally would change the scale.

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## Azélor

Actually it would be red, almost purple.
It is very unlikely to have a star like that. 
About 1 out of 120 000 stars.

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## Azélor

I did this with the planet.
Half the time was spent figuring out how to place the shadows on Saturn.

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