IE, if I wanted calculate a twin moon orbit for a fantasy world that revolves around binary stars, would it be easier to just ask the physics stack exchange instead of the world building stack exchange?

It seems to me like the world building forum is poorly defined in relation to such questions, and those who disapprove of questions that could be in either tend to have louder voices than those who would welcome them.

And since breaking down a question into a single question often make it more suitable for another stack exchange IE instead of asking "what would a planet with two moons be like" I need to ask "what orbits could two moons take around a single planet", "what kind of tides do two moon planets experience", and "how would moths evolve if there were two moons in (answer to first question) orbit around our planet?" Making these suitable for Astrophysics, physics, earth science, and biology stack exchanges instead.

If anything, world building looks like an less useful half combination of writing and sci-fi/fantasy, in which it does the work of neither quite as well, but also hates questions from physics or biology that are important to world building.

At this point I can't even figure out whether the title is what I mean, or if I'm straight up rejecting the world building exchange's core ideals. Anyways, either way may be biased or whatever so don't mind all the crunchy bits of salt.

  • $\begingroup$ For reference, this is the official bit on how and what to ask about on WB. How to ask $\endgroup$
    – James
    Commented Aug 22, 2018 at 20:42
  • 2
    $\begingroup$ Stack Exchange sites are not forums, they are stacks. $\endgroup$ Commented Aug 22, 2018 at 21:46
  • 2
    $\begingroup$ @Renan forum : a medium (such as a newspaper or online service) of open discussion or expression of ideas $\endgroup$ Commented Aug 22, 2018 at 22:02
  • $\begingroup$ @ClayDeitas by that measure, Steam is a forum since it allows comments on games. $\endgroup$ Commented Aug 22, 2018 at 23:14
  • 2
    $\begingroup$ @Renan I would argue that that isn't the purpose of steam, but yes, technically all comment sections are forums. $\endgroup$ Commented Aug 22, 2018 at 23:29

5 Answers 5


You should ask a question on WorldBuilding.SE if you are interested in the perspective of worldbuilders.

There are times when people can ask a question in similar form on multiple sites. But the different sites will always have a different focus. Physics.SE might very well answer you orbital-mechanics question if it's about real-world physics, but they might not like you describing fictional planets. On WorldBuilding you can also get frame-challenges more often that tell you "What you asked can be answered the following way: [answer] - but there might be a better approach to achieve what you want: [frame-challenge]".

There are also many topics that don't work well or at all on other sites. is a topic that comes up quite often here on WorldBuilding and wouldn't really be well received on Biology.SE or other sites on the network.

This site is also about stuff like the - which would definitely be off-topic on other sites.

All in all it depends on your questions. Maybe for your specific questions other sites would be more useful, but for many other people this site offers the kind of jack-of-all-trades thinking that they need to help them with their worldbuilding problem.

An important part is often how you phrase your question. Your example "What would a planet with two moons be like?" wouldn't work here because that's a lot of stuff you are asking about. So much that everyone could talk about about a different thing - society, physics, biology, ... - and all of those combined wouldn't be enough to sufficiently answer your question. But the question is: do you really need all of that information? What type of project do you have that you need to know absolutely everything about this setup and why can't you state some things and simply assume that's correct? For example most books gloss over... basically everything about the world, except for the things that are interesting to the story. Is your main character for example an astronomer? Then we should probably focus on astronomy.

If you have problems with phrasing your question you can check out the Sandbox on Meta, which is designed to help people that are having problems with their posts.

We are not a combination of SFF.SE and Writing.SE. SFF.SE is about canon worlds and only answers such questions, whereas WorldBuilding is about creating new worlds. Writing.SE is about help with the craft of writing, not with building your world or story.

In general we accept every question that aligns with our guidelines, such as:

  • Must be specific and answerable: What problem are you trying to solve?
  • Must include context: What are you trying to accomplish? Context gives people writing answers an idea of what your end state will look like and why you want to get there.
  • Must include restrictions/requirements: What will make one answer better than another? If any answer is equally effective your question is not properly constrained. How can this be executed? What tech, timeline, magic or other criteria apply to the situation.
  • Should include research: What ideas have you considered, or what information have you already looked at or failed to find?

A question should only be migrated if it is off-topic here and on-topic on the other site. You might get a few people that are saying you could also get an answer to a question on a different site, but, simply put, that's up to you:

What kind of perspective are you looking for? A scientists or a worldbuilders perspective?


Huge ramble short; Worldbuilding is about fiction and pretty much dedicated to hypothetical questions, this gives you a huge advantage when it comes to getting information useful to you in forming a new world. The other sites you have mentioned may give you hard, real world, facts that you can use but often don't tolerate hypothetical questions at all, I know they last a few minutes at best on the Earth Science stack for example, and if they do answers are sub-optimal for fiction writing due to their focus on existing nature rather than possibilities.

  • $\begingroup$ Sure, hypothetical questions are tolerated here. But unfortunately, grossly erroneous answers get many upvotes. Effectively, you trade leniency for inaccuracy. $\endgroup$ Commented Aug 28, 2018 at 3:25
  • $\begingroup$ @ChrisStratton "Grossly erroneous" is a point of view, what I find a dead loss a lot of other people may find helpful with tangentially, or even directly, related problems. $\endgroup$
    – Ash
    Commented Aug 28, 2018 at 10:41
  • $\begingroup$ No, erroneous factual statements are simply wrong. Deflating true/false reality to "opinion" is a key source of the problem. $\endgroup$ Commented Aug 28, 2018 at 11:28
  • $\begingroup$ @ChrisStratton Like I said that's a point-of-view, not everyone's. Remember in fiction true/false reality does not necessarily exist, and if it does there's no reason it's the same true/false reality we experience. $\endgroup$
    – Ash
    Commented Aug 28, 2018 at 15:33
  • $\begingroup$ Completely invented realms are one thing; but there are lots of questions asking what are essentially hard sci fi feasibility questions, which get grossly erroneous answers. The specific erroneousness of these is not a matter of opinion - it is a matter of fact. And it's not as if the respondents mean to be inventing fictional science; they think that what they are saying is correct, because they do not actually understand the topic they are answering a question about. This is a fine place for pure invention, but a poor one for factual basis research and feasibility. $\endgroup$ Commented Aug 28, 2018 at 16:04
  • $\begingroup$ @ChrisStratton One last try at making an argument that gets my point across, believe me when I say that even, possibly especially, in the real world "fact" itself is a matter of opinion. For example how many real people believe the world is flat again? $\endgroup$
    – Ash
    Commented Aug 28, 2018 at 16:10
  • $\begingroup$ No, fact is not a matter of opinion. Beliefs are not facts. It is an easily proven fact that the world is not flat. Someone who believes it is, is ignorant. That's an extreme example, but its a good example of precisely the kind of issue with many answers here. Terry Pratchett writing a fictional flat world was being inventive in the context of fantasy - which was fine. The issue is with people posting answers they (and many other subject non-expert participants) believe to be factually correct, which are in fact ignorantly wrong. Fantasy and falsehood are two different things. $\endgroup$ Commented Aug 28, 2018 at 16:51
  • $\begingroup$ @ChrisStratton "It is an easily proven fact that the world is not flat." Actually it's not, by definition you can't prove a negative, it may be a fact that the Earth is round but that's not the same thing at all. "Round" has a number of meanings and applications to that issue for a start. Einstein put it well "There are things in this universe that we are yet to be proven wrong in our understanding of, that is all." Anyone who takes any answer verbatim, from anyone, anywhere, about anything without independently fact checking the data is a fool and deserves what they get as a result. $\endgroup$
    – Ash
    Commented Aug 28, 2018 at 16:55
  • $\begingroup$ I'm sorry but you are simply mistaken. There are many kinds of negatives which can be proven. In fact the most obvious attempts to prove that the world is round, are more accurately proofs that it is not flat. Proving the approximately sphere-like nature is quite a bit harder. In effect, you've proven precisely the point - lots of people here toss around things they really do not understand, not as intentional fantasy, but rather because they simply don't understand what they are talking about. $\endgroup$ Commented Aug 28, 2018 at 17:07
  • $\begingroup$ @ChrisStratton You're wrong but I'm bored now so whatever you choose to believe. $\endgroup$
    – Ash
    Commented Aug 28, 2018 at 17:21
  • $\begingroup$ It's not a question of what I believe, it's a question of what is scientific fact. But you've demonstrated that that the concept of facts isn't within your thought process, which only allows for personal beliefs. This completely proves my point, by demonstrating the type of attitude which makes this site unsuitable for doing factual feasibility research on the premises underlying story ideas. $\endgroup$ Commented Aug 28, 2018 at 17:44
  • $\begingroup$ @ChrisStratton You may not have experienced this but I know that "scientific fact" is not the concrete entity you seem to think it is; I've lived long enough to see fiction become science and, more importantly, vice versa. $\endgroup$
    – Ash
    Commented Aug 28, 2018 at 17:48

Ash and Secespitus have basically covered it, but I think the main difference is that World Building is far happier to deal in the theoretical and hypothetical than other stack exchanges.

I don't frequent the various science stacks but it is my understanding from other users here who do that questions like "how would moths evolve if there were two moons in (answer to first question) orbit around our planet?" probably wouldn't be welcomed on Biology. Whereas it would be fine here (if maybe a bit broad?).

For straight up real world problems, yes you probably are better asking elsewhere or using Google, but for anything that involves a bit of creativity or a cross over between multiple branches of science that's where World Building shines.

  • $\begingroup$ The problem is in vetting the responses to open-ended questions for accuracy. It's almost as if you'd have to take the responses here, and individually ask if they are realistic on subject matter sites. Most, unfortunately, will quickly be shot down by those who actually understand the topics. $\endgroup$ Commented Aug 28, 2018 at 3:27


Worldbuilding.SE is not as effective as a place for one-stop shopping than it would be as but one specialty shop among many specialty shops. Of course, much will depend on what you actually want out of your question!

  • If what you want is a bunch of numbers and a nice orbital diagramme, then by all means, ask on one the science, astronomy, or physics forums. That's where the experts in those fields hang out.
  • If what you want is speculation on what this might look like in the sky, how two moons might affect cultural evolution, astrology, folklore, etc, then Worldbuilding.SE is exactly and precisely the place for you!! This is where the experts in our field hang out!

I agree with you that WB.SE is "poorly defined in relation to such (plug-in-the-numbers, science, or maths) questions". There is currently, and I'm sure has been, not a little debate as to what kinds of questions should be taken as on or off topic. You can see in Meta some of the more recent discussions.

For example, if you posted the question "How do I go about calculating the orbit..." or "What would the orbit of XYZ look like..." I would argue that these are obviously off-topic here and belong some~anywhere else but here. My opinion is that all that mechanical substrate can best be done elsewhere; then come here when you're actually ready to do some actual worldbuilding! Other people disagree and argue that no matter how tangential a question might be to an invented world, it should be on-topic here. shrug I'm for the art; others are all about the mechanics. That's never going to be resolved to everyone's satisfaction in a shared authority forum like this.

I disagree entirely with you re "less useful half combination of writing and sci-fi/fantasy". This could be taken as actually rather a slap in the face to many of us who are experienced writers & geopoets. If you ask the right kind of questions in this forum, you can receive spectacular & creative advice. Me, I hold that as closer to our core ideals than the orbital physics & mathematics that underly worldbuilding proper.


Yes. If you want an answer grounded in facts and science, you need to ask elsewhere.

Unfortunately, Worldbuilding SE seems to be dominated by early ideas that sound good, even though deeply flawed in a way that is immediately obvious to subject matter experts. But because subject matter experts do not generally inhabit the site, but only find their way over from teasers in the sidebar of other SE sites, grossly erroneous answers are often well entrenched with many uninformed upvotes before anyone with actual knowledge arrives.


If you're content with ideas that sound good to the ignorant, ask away.

But if you want to validate that specific ideas sound plausible to the informed, then realistically you have to ask somewhere else, where there is community of actual expertise on the topics involved.

Of course in asking on topic sites, you'll have to be careful to obey their rules. For example, you can't really ask "what X would enable a Y", rather, you have to ask specifically "could (specific) X be compatible with (specific) Y". ...be prepared for an earful about why it isn't.


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