# Understanding which materials can be found on planets

I am making a science fiction computer game where you can travel between planets. I would like the planets all to have some kind of differing materials. Now I have no idea about which kind of "materials" exist. I know an element is defined by the number of protons and the only thing that can change then are isotopes.

But a lot of planets would probably also have compound materials. And now I don't understand, do I just have universal freedom to say (while staying reasonable realistic), you have found material XYZ on this planet, it behaves like steel but is twice as light? And can something like plastics be just found on a planet? (And is plastic something special we humans have discovered and other races would likely not have discovered it, but maybe some other group of materials which behave very differently?)

So to make it short: While staying reasonably realistic, what are the kinds of materials I would expect to find on other planets and how much would they differ from what we have on earth?

I don't need to tell the player: The element you found has this and that chemical formula; I just want a rough idea of what is possible and plausible.

EDIT: Based on the comments I will specify my question.

The player starts on some random planet. I want the player to be able to find materials. The important properties of these materials are:

• How good are they for building houses
• How good are they for building spaceships

I will probably abstract all of that away into how hard, elastic and heavy they are and at which temperatures they differ in these properties.

I need to communicate the finding of these materials to the player and here is my problem. On a different planet, is it plausible that the player will find for example an isotope of some material which has some differing properties? Will it be plausible that he finds some very new compound material that humans have never thought of?

Or do the most planets look very similar in what they are made of to earth, such that the finding of new materials should be done with technology. I hope this clarifies my question a bit.

• Have you tried googling 'material' ? What do you mean by that word? You have a lot of different questions at once, try to limit it to one. What you are describing is something you find a lot in sci fi (that planet has mineral x and now gets enslaved to mine it!) But as you've noticed yourself that idea barely makes sense. You have a choice: find out what can actually be a realistic option (there are a lot of problems with it) or just so what most sci fi does: whatever. Mineralium can only be found on planet 3v for no reason. It's such an established concept that almost nobody will question it Feb 14, 2018 at 11:11
• A good idea for a question would be: first explain what you'd like to have, specifically, then ask whether it's possible and/or realistic. That way you'll get more informed answers. That is if you want realism. Feb 14, 2018 at 11:23
• You should have enough rep for the sandbox now. The problem btw with an idea like finding a material people never thought of (say some organism produces a great material for underwear) is noticing those properties. And finding it in the first place. There are too many possibilities to link that one out of millions of organisms to underwear. And then an advanced civ (i assume even ftl?) most likely be able to just synthesize it. How do we even know where to mine for something on earth? It will be impossible with unknown materials on an unknown planet. Feb 14, 2018 at 11:43
• Protip - Check Starbound. That game solved this same issue graciously. Feb 14, 2018 at 13:55
• Some things I can think of that might vary would be hydrocarbons, water, gases, metals, heavy metals, rare earth elements (used in high-tech gear like cell phones), and radioactives. Feb 14, 2018 at 15:40

You have to set clear (in your mind first, then in the game) the difference between raw materials and processed materials.

We don't mine plastics, we mine a raw material called oil and then process it to make plastics.

We don't mine aluminum, we mine a raw material called bauxite and then process it to make aluminum.

Raw material is what you will find on a planet, and you need the proper technology to harvest it. Then you need knowledge and other proper technology to process it for your purpose.

Depending on the level of details you want to implement in the game you can give in more or less details.

You can set a generic "mine" and according to the available technology you can process the ore to make steel or aluminum or gold, or you can set different mines each delivering different ores and thus different processed materials.

If other races do not too much upset the balance of your game, you can have alien traders on the planets you find. Sort of like the villagers in Minecraft. These gentle aliens have raw materials like lumber they take from forests, but also processed things like refined metals and made things like plastic. You can have these aliens offer anything the game requires.

You can have different races of aliens and so be able to guess what sort of stuff they might have. From the gameplay standpoint, aliens also jazz up a planet because they have faces and character and variety (even if they are all basically Minecraft villagers).

• I guess locals would be an actual legitimate source for previously unknown materials. They can even tell you what they are good for. I personally think any space age civ will be able to copy that stuff, but maybe it's cheaper not to. It has certainly happened on earth before from silk to potatoes Feb 14, 2018 at 12:09

Yes, you can find unique things but most things will be the same

Since this is for a game, I am assuming by planet you mean something a human could actually walk around the surface of in a suit, so no gas giants or super cold ice balls. And I am restricting myself to planets and possibly moons, not everything in space, asteroids would be easier to min in many ways.

Things every planet will have.

metals, glass (made from silica), and rocks. Any planet even close to earth like gravity will have lots of these. It is what they are made of. they might find more of some materials but they will not find much in the way of different materials, the laws of physics are still the same. Something however might be much easier to find on some, some planets might be rich in rare earth elements and they find unique minerals produced with them. There minerals on earth with interesting properties that only exist in a single place on earth, caused by a unique combination of conditions. So it is possible they might find a planet with lots of naturally occuring superconductors or something like that. Yes they could find something humans had never thought of but such thing will occur on planets with very un-earth like conditions and be rare, how useful they will be is more or less random.

things unique to earth (or planets with life).

everything unique ot earth is a product of life. Plastics, wood, rubber, petroleum, etc are all products of life (or refined from products of life) so a fictional planet with life may have them or may not that is up to you and what you want the life on the planet to produce. A planet without life should not have them with the possible exception of petroleum, there are some very rare circumstances, like some moons, which produce hydrocarbons seas, and that only gives you petroleum.

On the other hand planets with different life might well have completely different things produced by their life, wood might be unique to earth, milk and feathers will almost certainly be. Some planets might have life with iron teeth barbon fiber shells, or chitin trees. The vast majority of unique materials you find will be products of local life forms. I remember reading a story as a kid about an organism heavily poached in a galactic civilization becasue it produced a liquid that stayed a liquid even under hard vacuum and was used as spaceship lubricant.

so it really comes down to what you want to build your houses out of and what you use to fuel your starships. A wooden house will not be possible on a planet devoid of life, but a house on such a planet does not make a lot of sense either. Plastic is only going to come from a planet with a manufacturing factory to produce it.

Water will be your rarest resource, although some planets will be absolutely packed with it either as water or more likely as ice.

As L.Dutch said there is a big difference between raw and manufactured materials that needs to be considered.

• Rocky planets. Gas planets may not have these things (or they may not be reachable). Feb 14, 2018 at 19:37
• Water is common in space; it only gets rare near a star where it boils off.
– Yakk
Feb 14, 2018 at 20:07
• in space yes, on planets no, lots of things are easier to get out of asteroids than planets.
– John
Feb 14, 2018 at 23:56

Most planets should contain most elements and most types of molecules should be found on most planets (methane is a hydrocarbon).

The difference tends to be: which materials are found easily on the surface of the planet.

1. High tectonic/volcanic activity puts more gold, silver and heavy metals on the surface.
2. As has been pointed out, life gives larger molecules of many types (hydrocarbons, proteins, medical and poisonous molecules).
3. Water or past water gives salts and other molecules that are created when elements are dissolved in water. the presence of certain of these chemicals is why scientists are now convinced that Mars once had water.

On any planet, you should have the building blocks for #2 and #3 types. So, the question is just how much work/energy needs to go into providing them.

The #1 type are the tricky ones. If there is no tectonic activity at all, you might be SOL for those. There may be a few deposits from when the planet was still undergoing formation but you will have to find them.

I recommend two parameters for your material availability: quantity and availability.

Quantity is: how much is there to dig up or create. this one is pretty straight forward.

Availability is: how difficult it is to mine / find / process. Maybe a 1 to 10 scale.

10 is: walk outside and pick it up off the ground. In some areas gold and diamonds like this.

9 would be: tales some work. Wood is like this. Unless you are in a desert, you can find it just about anywhere but you need to cut it down and then process it into the sizes that you need (for lumber) or into a form that will be useful (pulp for paper or charcoal).

1 would be: Yes you can do it but why?

0 would be: it isn't present at all or you can't obtain it for some reason (not allowed to mine radioactives and rare earth elements tend to come mixed with radioactive elements).

Even the longest chain hydrocarbon can be created from carbon dioxide, water and some other commonly found elements. It is just that it takes a lot of energy to put the long chain molecules together and isn't worth it if you can get it from another source (and the transportation energy is less than the creation energy).

• Most planets should contain most elements, because the universe is old enough to have type V supernovas going on; (Supernova nucleosynthesis). Assuming those, it's down to quantity and availability +1 Feb 14, 2018 at 23:16
• “High tectonic/volcanic activity puts more gold, silver and heavy metals on the surface” ­– sure that this would be a trend across planets? Correct is, on Earth, heavy metals are mostly found in igneous formations, i.e. “stuff that has drifted up with the convection”, however overall the heavy elements obviously tend to sink down if the liquid interior permits it. I would have thought that you might find heavy metals more easily e.g. on Callisto, where there isn't a strong layered density seperation in the first place. Feb 14, 2018 at 23:42

Materials you can find on a planets are all some mixtures or raw elements.

Steel is an alloy $Fe_3C$ plus some additives and other elements with varying content.
Types of steel is exactly those additives and amount of $C$. You have mild steel, hard, carbon and so on.

So you theoretically could have steel occurring naturally in some planet with slightly different proprieties due to process it was created in but it would still follow certain properties. Because you can't change mass of an atom. OR you can but it change the atom so instead of $Fe$ you end up with copper for example.

and everything you will find on other planets, in our universe at least, will have the same atoms that ac the same way.

And of course you can have different weight of processed materials. But not because the components are different but because you are on a different planet with different gravitational field.

Everything what is on Mendeleev matrix you will find in other places of galaxy. With different quantity of course. Finding very new compound material that humans have never thought of is as possible as finding vein of Damascus steel occurring naturally on earth.

• So, what is the probability of finding a vein of damascus steel on earth? Feb 14, 2018 at 12:33
• @dot_Sp0T None. Theoretically steel could form naturally. But because it would not be stainless it would rust away faster than we started digging for it. Feb 14, 2018 at 12:53
• @SZCZERZOKŁY if you have a planet with hardly any oxygen then it wouldnt corrode. Feb 14, 2018 at 13:51
• @joojaa how would you create high temperature without oxygen? Feb 14, 2018 at 14:13
• @SZCZERZOKŁY pressure, sunlight, radiation... Feb 14, 2018 at 14:13