Planetology

[craenor]

When you're building a world, do you typically assume a very Earth-like planet (sun rises in the East, sets in the West, four seasons, normal day/night cycle, a moon with expected tides?)

Or, do you consider variations in the basic planetology? Completely different seasons? A varied day/night cycle? Wild swings in the tides based on the position of multiple moons? Or even extreme tides based on the close proximity of a companion planet (or perhaps this world is the moon of a gas giant).

 

[Chilari]

I tend to stick with an Earth-like planet, though generally with different landmasses but otherwise the same in essentials. I'd rather not mess around with the cosmic side of things. There's enough scope with the world as it is, roughly speaking, and I don't feel I understand enough about planets and stars and moons and tides to just dabble in it, I'd have to research it in detail - and I'd rather spend that time crafting a solid story and an interesting cultural settling

 

[Steerpike]

I tend to stick with earth-like as well. Unless you really know what you're doing, tweaking a few of these things could have all kinds of downstream effects that some readers are going to notice as inconsistencies. When I'm reading, though, I tend to give the author a lot of leeway unless there is some glaring issue (like a moon that is so close it takes up 3/4 of the sky during daytime, but with no perceivable effect on how the world works, etc.).

 

[T.Allen.Smith]

I see no reason to make changes or variations unless those changes, or their effects, have a reason.

Meaning, if I'm writing a story where the sun rises in the west, or the days are only a few hours long, those differences need to have story importance...they need to affect characters with a purpose and not just offer up differences for the sake of difference alone.

Otherwise, you're just giving out meaningless details for your reader to chew through that have no other purpose than to provide setting detail. This will pull the reader's attention away from the important parts...the story itself.

 

[Zero Angel]

When you're building a world, do you typically assume a very Earth-like planet (sun rises in the East, sets in the West, four seasons, normal day/night cycle, a moon with expected tides?)

Or, do you consider variations in the basic planetology? Completely different seasons? A varied day/night cycle? Wild swings in the tides based on the position of multiple moons? Or even extreme tides based on the close proximity of a companion planet (or perhaps this world is the moon of a gas giant).

Yes.

I tend to stick with earth-like as well. Unless you really know what you're doing, tweaking a few of these things could have all kinds of downstream effects that some readers are going to notice as inconsistencies. When I'm reading, though, I tend to give the author a lot of leeway unless there is some glaring issue (like a moon that is so close it takes up 3/4 of the sky during daytime, but with no perceivable effect on how the world works, etc.).

There's lots of ways this is able to be accomplished though. I mean, if Lucas can turn a mistake in thinking parsecs was a unit of time into a description of how hyperspace travel works, then anything's possible, right?

In fact, you can just say, "Hey, this is how it works, yins all figure it out" and there will be mathematics and science that could explain what they want to happen.

In the multiverse of WotA, I use magick as my catch-all to any naysayers. Not in the whole, "dragons can fly 'cuz they're magick," but more "In the beginning, there was the magick interaction, then the strong force, then the electroweak interaction which split into the electromagnetism force and the weak interaction, and so on." So magick is literally in the physics of my universe, and when you have fermions interacting with bosons WITH MAGICK, then I get to do whatever I want. The end

Although I do go into some deep water in some of the explanations, and have been working on the Wiki for WotA (sorry to people that visit that new articles haven't been uploaded in a while ), so I don't just start out of the bat with, "I win, the end." That's just my ending argument.

 

[Sheilawisz]

I read somewhere that if we did not have the moon, our planet would spin in very different and even unpredictable ways and we would not have seasons at all... not to mention that the weather would be totally crazy, and the world would be inhabited by a variety of strange forms of life that would be different to everything we know.

Some people say that the Earth and the moon are a double planet, because of how important the moon is for Earth =)

Having multiple moons would create a very different world, as well (it would depend on the size of the moons, and how far they are) and also a planet with a slower or maybe a faster rotation than Earth's would result totally different and alien-like from our point of view!!

However, personally I do not consider such concepts for my Fantasy stories:

My main Fantasy universe is an endless and bottomless ocean where worlds are continent-size islands and everything exists under an unlimited starry sky, because I go for the unrealistic and dream-like style of Fantasy.

Anyway, Planetology sounds cool!!

 

[Zero Angel]

I read somewhere that if we did not have the moon, our planet would spin in very different and even unpredictable ways and we would not have seasons at all... not to mention that the weather would be totally crazy, and the world would be inhabited by a variety of strange forms of life that would be different to everything we know.

Some people say that the Earth and the moon are a double planet, because of how important the moon is for Earth =)

Hi so, some of what you've heard is reasonable. It is accepted scientific theory now that the moon acted to slow down our rotation and affected our axial tilt, without which there would probably not be life on earth.

I've never heard the idea that the Earth and moon form a "double planet" and I hope that this was exaggeration to emphasize how important the moon is to Earth, or some sort of New Age-y description. Since 2006, a planet is required to (1) be in orbit around the sun and not a satellite or star (thus removing the moon from consideration off the start), (2) have enough mass to achieve hydrostatic equilibrium (i.e. be round), and (3) clear the neighborhood about its orbit.

This is why Pluto was demoted, there's actually several objects out there in the Kuiper belt along with Pluto, and it's not even the largest. In fact, there's argument that Charon (its largest moon of Pluto) shouldn't even be considered a moon since the barycenter (center of mass) of their system is between both planets and not contained within Pluto (as it is presently with us and the moon).

Interestingly (I suppose), is that the same convention basically places all asteroids that have achieved hydrostatic equilibrium and aren't satellites as dwarf planets—including Ceres, which is between Jupiter and Mars. As far as I know, the terms "asteroid", "moon", and "satellite" have not been specifically defined, so we kinda' just use a wishy-washy system for those.

Reasonable idea of asteroid:

An object in orbit around the sun that is not a star or satellite and has not achieved hydrostatic equilibrium. —yikes, this would include comets -_-​

Reasonable idea of a satellite:

An object in orbit around another object. Specifically, where orbit implies that the barycenter (center of mass) of the system is within the larger object​

Reasonable idea of a moon:

A satellite that has achieved hydrostatic equilibrium.​

I wish they would just define these things already!

Wait, has this been a tangent??? Apologies!

 

[ThinkerX]

I've created many worlds down through the decades and have gone both ways with them.

Had one world (inspired in part by 'Endor' from Star Wars and some real world hard science calculations) that was a moon orbiting a gas giant. Really funky day night cycle, plus some weird tides. The extra's got to be too much to keep track of. I merged that world with a more normal one.

Had another world that was fairly normal - except that it was set in a wide binary system. The planet orbited one star, but every hundred years the second star (a small, faint red dwarf) in a much more eccentric orbit would make a close pass, going from a bright dot in the sky to an actual second sun. I finally decided the concept was too close to another I had going and merged that world with another as well.

Currently, I have one world for an SF setting which, in order to work has to have a pretty severe, fixed axial tilt - something on the order of 60 - 80 degrees. North pole pretty well baked, south pole dark and froze over, and a narrow band in between with a regular day/night cycle. I'm still contemplating the exact details on this world: I'm not sure if I can phausibly match it up with what the story calls for.

My primary fantasy world is fairly normal...apart from being something like 60% land. Lots of landlocked or nearly landlocked seas, only one true ocean.

As to the earth-moon pair being considered a 'double planet'...the answer is 'almost'. Prevailing theory is that the moon is whats left of a Mars sized planet which actually struck earth way back in the dawn of geological history. The collision slowed this rogue planet down enough to where it took up orbit around the earth. A billion years ago, the moon orbited much, much closer to the earth than it does now.

The moon acts as a stabilizer for the earths rotation. Without it, the earth would be subject to frequent pole shifts.

 

[Jamber]

I suspect it all boils down to your intention in terms of genre. If you start creating a planet with significant differences to earth, and if you use them in a scientifically rational way, readers may be placing you more in a sci fi camp (the question being whether that's your intention).

I feel fantasy tends to work more with worlds that have some relation to our histories, myths or other stories than scientific logic (emphasise 'tends'). Thus the 'moon' doesn't just illuminate the night sky, wax and wane, and move the tides, so a second moon would arguably carry a different kind of import than just the science (if that makes sense).

These tendencies don't mean a book can't contain both sets of elements, or consciously work between sci fi and fantasy, namely having a physical universe complete with a solar system and planets as well as having mythical or magical elements, but I feel there's a lot of work to do smoothing the seams.

What I do is try to think about subgenre/genre in terms of what outcome I want (based on the mood or ideas I'm toying with), then I take it from there. Ultimately rules are made to be broken... But I like to know before I commit finger to keyboard what kind of thing I'm aiming to create (or for that matter why I want to break a particular rule).

Hope this makes sense,
Jennie

 

[Rob P]

Having written about multiple worlds, I would say only one thing.

Differences to Earth only need to be engineered if scenes take place in multiple worlds for the story. Gravity, composition of atmosphere, temperature, etc etc. It would defy belief if every world was related.

Otherwise in Fantasy, linking with what we know and the glorious anomolies of life and environment we have here on Earth is enough.

 

[mbartelsm]

I tend to mess with continents and a few laws of physics, otherwise the planet behaves just like earth.

 

[Nihal]

I say: Why not?

It's easier to stick with Earth-like worlds, specially when you have no reason at all to change the world. Yet, I think different worlds ideas can be used to add a flavor, if not as an important element of the story. And to do this, IMO, you don't need to go so far to explain every single aspect of the world. You shouldn't, to use this technique don't info dump.

Present the world's differences slowly, integrating them to the story's pace and don't explain all technical details (as how many planets orbit this world's sun) unless they're relevant to the plot, staying clear of technical vocabulary too. You may want to know them but the readers aren't supposed to learn of those things unless you decide to compile an appendix with that information.

Here goes an example of a different world where it's shape drives the plot. It's from an anime called Last Exile, not a book. ;x

Spoiler: Prester World

It's a steampunk story with magical elements. In the end you discover that the world, which was always slipt in two with a great storm separating the two halves is actually a hourglass-shaped ship.

 

[wordwalker]

And remember one thing: the sun always rises in the east, because "East" is what we call where the sun rises.

(Okay, I guess if everything from the creation myth on down said something like the pole star was more important than the sun, that could define North, and if the sun rose to the left of it that might make it the West. Instead, a lot of medieval maps went the other way and put East at their top-- which makes some sense.)

 

[Zero Angel]

And remember one thing: the sun always rises in the east, because "East" is what we call where the sun rises.

(Okay, I guess if everything from the creation myth on down said something like the pole star was more important than the sun, that could define North, and if the sun rose to the left of it that might make it the West. Instead, a lot of medieval maps went the other way and put East at their top-- which makes some sense.)

Great point! Here's the etymology from etymonline.com:

Old English east "east, easterly, eastward," from Proto-Germanic *aus-to-, *austra- "east, toward the sunrise" (cf. Old Frisian ast "east," aster "eastward," Dutch oost Old Saxon ost, Old High German ostan, German Ost, Old Norse austr "from the east"), from PIE *aus- "to shine," especially "dawn" (cf. Sanskrit ushas "dawn;" Greek aurion "morning;" Old Irish usah, Lithuanian auszra "dawn;" Latin aurora "dawn," auster "south"), literally "to shine." The east is the direction in which dawn breaks. For theory of shift in sense in Latin, see Australia.

A lot of those ancient maps are pretty crazy looking, but until we decide how to orient ourselves (magnetic north? sunrise? sunset?), we can draw them however we want. In fact, it would make sense to draw the world upside down and think to ourselves, "the sun rises in the 'west' and our compasses point to the 'south'," even though in that world, people would have no concept of the ENTIRE world unless they had circumnavigated it or something.