Random Worldbuilding Questions (Biology, Geography, Society, etc.)

[Tirunedeth]

Originally Posted by TheWombatOfDoom

In the world I've been brewing, I wanted to have a large moon (about 5 or 6 times as big as our luna in the night's sky). I had this idea that my moon measures the centuries by it's stages - waxing, full, waning, new. Basically a VERY slow stage cycle. Actually...even longer than that would be ok as well.

So basically think of looking up every night and seeing nearly the same cycle for your entire life. Other areas of the world would obviously be on different parts of the cycle based on where they viewed it from, but what kind of explination actually would make this possible. I know it's quite...far fetched. But I'm fairly confident if it were just right, it would work. I'd just have to have it that the moon was always at the same angle to the sun in it's orbit as the earth rotated, with a slight angle to make the change...right?

Thoughts? How would that effect the planet in terms of tides, seasons, orbit?

If the moon has an orbital period which is very close, but not quite, the same as the orbital period of the planet, you would wind up with what you're looking for. Unfortunately, I don't think such a situation can ever be stable. The distance below which stable orbits around a planet are possible follows the same progression as the distance at which the moon will have the same orbital period as the planet, so they never end up passing each other.

It's not quite what you wanted, but would a moon which only rises once every few hundred years work? You could achieve that by having the planet be almost, but not quite, tidally locked to the planet.

[jseah]

You can fake the lunar cycle. =D

Have the moon sit on the Lagrange point trailing the planet (so it doesn't actually orbit). Have the moon's surface have a dark and light side, so one side of the moon absorbs light, the other reflects it. Now have the moon rotate. Slowly.

Tada, moon phases of arbitrary length.

Too bad about the rise and setting though. The moon will rise and set just like the sun (it will come a quarter of a day earlier or later, depending on which way your planet rotates)

[Tirunedeth]

Originally Posted by jseah

You can fake the lunar cycle. =D

Have the moon sit on the Lagrange point trailing the planet (so it doesn't actually orbit). Have the moon's surface have a dark and light side, so one side of the moon absorbs light, the other reflects it. Now have the moon rotate. Slowly.

Tada, moon phases of arbitrary length.

Too bad about the rise and setting though. The moon will rise and set just like the sun (it will come a quarter of a day earlier or later, depending on which way your planet rotates)

A clever idea, but there's one issue with it: the Lagrange points (well, the ones that are stable long-term) are the same distance from the planet as the primary star is. So you'd need a star-sized object for it to appear 5-6 times the size of the Moon. If it weren't for that, it would be a really good idea, though. One of Saturn's moons, Iapetus, actually has the same sort of light/dark hemisphere thing you're suggesting, too, so that part isn't so implausible.

[TheWombatOfDoom]

Originally Posted by Tirunedeth

A clever idea, but there's one issue with it: the Lagrange points (well, the ones that are stable long-term) are the same distance from the planet as the primary star is. So you'd need a star-sized object for it to appear 5-6 times the size of the Moon. If it weren't for that, it would be a really good idea, though. One of Saturn's moons, Iapetus, actually has the same sort of light/dark hemisphere thing you're suggesting, too, so that part isn't so implausible.

What if it was a similar sized moon to ours, but instead the atmosphere magnified it, kind of like how when the moon approaches the horizon, it gets the illusion that its bigger?

[Tirunedeth]

Originally Posted by TheWombatOfDoom

What if it was a similar sized moon to ours, but instead the atmosphere magnified it, kind of like how when the moon approaches the horizon, it gets the illusion that its bigger?

First, my understanding of the "Moon near the horizon appears larger" phenomenon is that it's an optical illusion, not related to a magnifying effect in the atmosphere. IIRC, the atmosphere actually causes objects near the horizon to be very slightly smaller than those higher in the sky. Also, it would require an awful lot of magnification to make a Moon-sized object appear 5-6 times bigger than the Moon appears from Earth, at a distance of 1 AU (the distance form the Earth to the Sun). The Moon is about 400 times smaller than the Sun, so to appear 5-6 times larger at the same distance would require magnification by a factor of 2000-2400. Even something the size of Jupiter would require magnification by a factor of about 50-60 to reach 5-6 times the size of the Moon, and it would be rather difficult to get a gas giant with a light/dark hemisphere divide like what you're looking for. And I'm not even sure how you would get the atmosphere to magnify things that much; while I think the atmosphere could function a lot like a lens, I don't think you would get anywhere near the magnification needed to make this scenario work.

I did just have an idea, though. It might be possible to make a horseshoe orbit work. The "moon" in this case would actually be a gas giant, with the planet in a horseshoe orbit with respect to the gas giant. If I'm visualizing things correctly, the two would move relative to each other only very slowly, which would mean the phase of the gas giant would change very slowly. This does run into the same sorts of apparent size issues as the Lagrange point idea, though. If the planet in this scenario approached the gas giant to within 12 million kilometers, as 3753 Cruithne does Earth, then at closest approach it would appear to be only about 30% larger than the Moon does. When the gas giant is on the other side of the star, it would appear as a point. Also, the gas giant would never completely disappear, since it would never be between the planet and the star.

You could solve the apparent size issue by having the planet in a smaller orbit around a dimmer star, and having it approach the gas giant more closely. Although if you get much closer than 12 million km, the gas giant is going to have to have no moons of significant size, or their gravity could disrupt the planet's horseshoe orbit. The time around closest approach would also be very interesting, since the planet would start experiencing tidal effects from the gas giant. For a Jupiter sized planet and the 12 million km closest approach, it looks like the tides would be about the same as those due to the Moon on Earth. However, they could cause problems since they aren't something people on the planet would have to deal with except at the time of closest approach. And the gas giant could have captured asteroids, which could hit the planet when it gets close.

Another potential problem with the horseshoe orbit is that when the gas giant is at its brightest, it would only be in the sky during the day. However, it might still be visible - Venus is visible in the daytime sky, and this gas giant would be much larger than Venus and not too much further away.

[TheWombatOfDoom]

Originally Posted by Tirunedeth

First, my understanding of the "Moon near the horizon appears larger" phenomenon is that it's an optical illusion, not related to a magnifying effect in the atmosphere. IIRC, the atmosphere actually causes objects near the horizon to be very slightly smaller than those higher in the sky.

All good points. Scratch the magnification idea...what if the "planet" we've been speaking of is actually a moon of a planet, say this dark light planet from earlier, or the gas giant?

I don't think the dimmer star idea is viable, since for a world to orbit the dimmer star in this system (the white dwarf) it would have to be VERY close in order to sustain life (about 0.005 to 0.02 AU from the white dwarf).

I suppose we could shoot for just a little bigger in any case. I just liked the idea of a huge moon in the sky. But just a bit bigger would suffice.

One other question - does everything orbit the same direction?

[Ksheep]

Originally Posted by TheWombatOfDoom

One other question - does everything orbit the same direction?

It doesn't have to, but typically does, due to how bodies are formed (protoplanetary disk circling around the star). Easiest way to account for something orbiting contrariwise is to say it was an inter-stellar planet that got caught by the star. Granted, this will probably result in it not being in the same elliptic plane (much more likely for it to be off-kilter, similar to Pluto), and the orbit is likely to be much more elliptical than other planets, but it is possible.

[Tirunedeth]

Originally Posted by TheWombatOfDoom

All good points. Scratch the magnification idea...what if the "planet" we've been speaking of is actually a moon of a planet, say this dark light planet from earlier, or the gas giant?

I don't think the dimmer star idea is viable, since for a world to orbit the dimmer star in this system (the white dwarf) it would have to be VERY close in order to sustain life (about 0.005 to 0.02 AU from the white dwarf).

I suppose we could shoot for just a little bigger in any case. I just liked the idea of a huge moon in the sky. But just a bit bigger would suffice.

Having the "planet" be a moon of the gas giant runs into the same problems as having a moon orbiting the planet: there's no stable orbit for the moon which will have the planet showing the same phase at all times. The light/dark planet is going to have problems with the interaction between the real phase and the light-dark hemispheres; sometimes the lightly colored hemisphere will be on the far side of the planet from the star, for example.

As far as the dimmer star, I was thinking making the main star dimmer, not moving to a dimmer star in the same system. It sounds like you've already got an idea of what you want the system to look like, though, so maybe that's not possible.

[Ksheep]

The "planet" could be at the L1 point, but that would be a fairly tenuous position, and would be almost impossible for it to occur naturally. But it would allow you to have a "moon" that appears 5 to 6 times larger than Luna. You could also take the "half white, half black" planet with very slow rotation. The moon would only be visible at night, with the planet being immediately between the "moon" and the sun(s).

As for how it got there, just say a wizard did it…

[TheWombatOfDoom]

Originally Posted by Ksheep

The "planet" could be at the L1 point, but that would be a fairly tenuous position, and would be almost impossible for it to occur naturally. But it would allow you to have a "moon" that appears 5 to 6 times larger than Luna. You could also take the "half white, half black" planet with very slow rotation. The moon would only be visible at night, with the planet being immediately between the "moon" and the sun(s).

As for how it got there, just say a wizard did it…

@Tirundeth - Yeah, I guess you're right. I'm trying at least! Haha. I'm not sure I'd like making this a dimmer star. Though I am making other planets in the system, one of which will sustain life (or at least had at some point).

@ksheep - As for the counter clockwise orbit, would the sun be able to spin counterclockwise too to make it less elliptical?

As for the L1 idea. Almost impossible seems like something people have said constantly about the chances of earth coming into existance. I don't mind almost impossible, as long as it scientifically makes some sense. So, can I have a sumary of what we just figured out? @.@ I'm still a little confused about Lagrange Points. Didn't really cover much on that in my Uni classs.

I want to thank the both of you for helping in any case. I've been mumbling to myself about these big balls of wibbly wobbly stuff for ages. Hopefully we can work something out for this slow rotation thing...ugh. I guess I should have known unique = nearly impossible/impossible to have happen

[Ksheep]

Originally Posted by TheWombatOfDoom

@ksheep - As for the counter clockwise orbit, would the sun be able to spin counterclockwise too to make it less elliptical?

As for the L1 idea. Almost impossible seems like something people have said constantly about the chances of earth coming into existance. I don't mind almost impossible, as long as it scientifically makes some sense. So, can I have a sumary of what we just figured out? @.@ I'm still a little confused about Lagrange Points. Didn't really cover much on that in my Uni classs.

Spin of the sun would not effect planets (at least, not significantly). So…*yeah, that wouldn't fix the eccentricity of the orbit.

On the L1 idea, the L1 point is very small, compared to L4 and L5, which are largish areas 1/3 of an orbit in front of and behind the planet in orbit. L1 is the point where the gravitational pull of the planet cancels out the pull of the sun. It is, effectively, a single point, and the center of mass of the object you want held there has to be right on that point. This will be made even more difficult, since you have this set up as a binary star, although you could have it so it's between the planet and the focus of the two stars (the point they both orbit around, effectively the center of mass of the two stars). The only way I can think of for how a natural satellite could end up in the L1 point is if a large enough asteroid struck the satellite at just the right angle and at just the right time to cancel out the excess velocity and hold it in place at said point. Highly unlikely, but in an infinite universe, I'm sure that it could happen somewhere.

[Tirunedeth]

Originally Posted by TheWombatOfDoom

@Tirundeth - Yeah, I guess you're right. I'm trying at least! Haha. I'm not sure I'd like making this a dimmer star. Though I am making other planets in the system, one of which will sustain life (or at least had at some point).

@ksheep - As for the counter clockwise orbit, would the sun be able to spin counterclockwise too to make it less elliptical?

As for the L1 idea. Almost impossible seems like something people have said constantly about the chances of earth coming into existance. I don't mind almost impossible, as long as it scientifically makes some sense. So, can I have a sumary of what we just figured out? @.@ I'm still a little confused about Lagrange Points. Didn't really cover much on that in my Uni classs.

I want to thank the both of you for helping in any case. I've been mumbling to myself about these big balls of wibbly wobbly stuff for ages. Hopefully we can work something out for this slow rotation thing...ugh. I guess I should have known unique = nearly impossible/impossible to have happen

To understand Lagrange points, imagine that you have two objects. I'll just use the Sun and Jupiter in this case, to make everything easy to refer to. Because Jupiter is pulling on the Sun as it orbits, Jupiter doesn't actually orbit a stationary Sun; they both orbit their center of mass, which is referred to as the barycenter (in the case of the Sun and Jupiter, this barycenter is actually outside the Sun). Now, if you put a third object, such as an asteroid, somewhere, it will be pulled by the gravity of both objects. However, if you put it just anywhere, the net gravitational force will point somewhere other than the Sun-Jupiter barycenter. This means that if you put the asteroid on the same orbit as Jupiter, for example, its orbit would be slightly different from that of Jupiter. The Lagrange points are points where the combined gravity of the Sun and Jupiter (or any other two bodies) points towards the barycenter and has precisely the same magnitude as the gravitational pull of the Sun on Jupiter. Therefore, an object at one of the Lagrange points will maintain the same position relative to the Sun and Jupiter (ignoring the influence of other objects, like Saturn). There are five Lagrange points, labeled L1 through L5. However, L1 through L3 are unstable; an object placed a small distance away from the Lagrange point will tend to get further away over time. Since it's impractical to put an object exactly on the Lagrange point, this means that any real object will eventually drift away from one of these points. L4 and L5, however, are stable, and any object a small distance away from them tends to get closer over time.

As for a summary, here are the ideas we've come up with so far:

1. Moon orbiting at a distance such that its orbital period is almost the same as that of the planet. This is the simplest scenario, but turns out to be completely unstable.

2. An object with one lightly colored hemisphere and one darkly colored hemisphere, sitting at the L4 or L5 Lagrange point. Allows for arbitrary phase periods, but the object would have to be incredibly large - on the scale of a star - to even show as a disk, let alone appear 5-6 times larger than the Moon.

3. The planet is in a horseshoe orbit with a gas giant. The gas giant would exhibit phases which would take a very long time to change, but would only be comparable in size to the Moon during the close approaches, and might not even show a disk most of the time. This could be alleviated somewhat by giving the gas giant rings. Also, there would only be tides during the close approaches, which could be good or bad.

4. An object with one lightly colored hemisphere and one darkly colored hemisphere, with the planet sitting at its L1 Lagrange point. The object would probably need to be larger than the planet, and even then there would be stability issues. I'm having difficulty calculating the distance at which the L1 point lies, but I'm pretty sure that even using a roughly 5 times Earth-mass body will only wind up looking roughly the same size as the Moon when viewed from its L1 point, maybe a little larger. Much bigger than that, and you're going to have difficulty justifying the very different hemispheres, due to its atmosphere becoming thick enough to be the only thing you're seeing.

And, well, all of these situations are unlikely to naturally, but I've been worrying more about whether or not these situations are physically possible before considering probability.

[TheWombatOfDoom]

Originally Posted by Ksheep

Spin of the sun would not effect planets (at least, not significantly). So…*yeah, that wouldn't fix the eccentricity of the orbit.

On the L1 idea, the L1 point is very small, compared to L4 and L5, which are largish areas 1/3 of an orbit in front of and behind the planet in orbit. L1 is the point where the gravitational pull of the planet cancels out the pull of the sun. It is, effectively, a single point, and the center of mass of the object you want held there has to be right on that point. This will be made even more difficult, since you have this set up as a binary star, although you could have it so it's between the planet and the focus of the two stars (the point they both orbit around, effectively the center of mass of the two stars). The only way I can think of for how a natural satellite could end up in the L1 point is if a large enough asteroid struck the satellite at just the right angle and at just the right time to cancel out the excess velocity and hold it in place at said point. Highly unlikely, but in an infinite universe, I'm sure that it could happen somewhere.

So effectively - I've got my main planet: Aldain. It's orbiting around the Main sun - Sirus, and the dwarf sun, Osirus. This "moon" that we've got in the sky, called Termin, is actually another object orbiting the suns that is half black and half light, due to a collision that set it into its current orbit. Therefore, Termin appears large in the sky, it cycles on a very slow rotation...and someone said it would only show up at night for some reason?

If not, I need a bit more input. Haha.

[Ksheep]

Originally Posted by TheWombatOfDoom

So effectively - I've got my main planet: Aldain. It's orbiting around the Main sun - Sirus, and the dwarf sun, Osirus. This "moon" that we've got in the sky, called Termin, is actually another object orbiting the suns that is half black and half light, due to a collision that set it into its current orbit. Therefore, Termin appears large in the sky, it cycles on a very slow rotation...and someone said it would only show up at night for some reason?

If not, I need a bit more input. Haha.

If the "planet" was at the L1 point of the much larger "moon", then yes, it would only appear at night because the L1 point is between it and the sun. The L1 point will effectively hold it locked in position, but even the slightest permutation of it's orbit (passing asteroid, large enough earthquake, etc) might throw it off and into orbit around the "moon" (the moon in this case being a gas giant, or something similar).

Anyway, I'd suggest asking Tirunedeth, as he appears to know more about such things. I only have a passing interest in astronomy, so some of what I've said may be a bit over simplistic or downright wrong, but from what I remember, that's how it goes.

EDIT: As for the earlier question about a planet going contrary to the normal orbit, I just found this in a conversation on the Kerbal Space Program reddit:

Six exoplanets out of twenty-seven were found to be orbiting in the opposite direction to the rotation of their host star — the exact reverse of what is seen in our own Solar System. The team announced the discovery of nine new planets orbiting other stars, and combined their results with earlier observations. Besides the surprising abundance of retrograde orbits, the astronomers also found that more than half of all the so-called “hot Jupiters” in their survey have orbits that are misaligned with the rotation axis of their parent stars.

[Conners]

I'm considering an animal that is able to copy what it hears, in a large variety of sounds (mice, birds, cats, people, etc.). Does it need just a new set of vocal cords and tongue, or is it more complicated than that?

[Ksheep]

Originally Posted by Conners

I'm considering an animal that is able to copy what it hears, in a large variety of sounds (mice, birds, cats, people, etc.). Does it need just a new set of vocal cords and tongue, or is it more complicated than that?

I think the easiest thing to do is mimic the Lyrebird, of Australia. Mockingbird might be a good starting point as well.

[Tirunedeth]

Originally Posted by TheWombatOfDoom

So effectively - I've got my main planet: Aldain. It's orbiting around the Main sun - Sirus, and the dwarf sun, Osirus. This "moon" that we've got in the sky, called Termin, is actually another object orbiting the suns that is half black and half light, due to a collision that set it into its current orbit. Therefore, Termin appears large in the sky, it cycles on a very slow rotation...and someone said it would only show up at night for some reason?

If not, I need a bit more input. Haha.

That doesn't sound too unreasonable, although as Ksheep notes the L1 point is unstable - although I suspect even a very large earthquake wouldn't be enough to destabilize things. Still, consider this: I am aware of no natural objects which are at an L1 point (we have several artificial satellites at the Earth-Sun L1 point). We see asteroids at L4 and L5 points and in horseshoe fairly frequently, but none in the L1 points. And the artificial satellites we've put in L1 points need to expend fuel to stay in place. So I'm not sure it would work very well. Still, it may very well be the best you're going to get, and you may just have to ignore the fact that it wouldn't actually quite work.

Of course, if your setting is fantastic rather than science fiction, you could just have the planet's position maintained by the gods or a powerful wizard. That would solve the stability issues, and it could introduce a nice potential plot where someone is trying to end that station keeping effect.

I've taken more of a look at the horseshoe orbits, and I've run across a few problems for them. First, the longer their period, the farther the closest approach distance is. You're looking for both a long period and a short distance of closest approach, so that's going to cause problems. Second, the horseshoe orbits involve changes to the orbital radius of the planet. That's going to cause shifts in climate after each close approach to the gas giant.

I'm just a physics undergraduate, so a lot of what I'm saying is probably pretty simplistic compared to what might be done when considering a real star system. I think everything I've said has been correct, but I have been known to make some pretty stupid mistakes on occasion.

Originally Posted by Conners

I'm considering an animal that is able to copy what it hears, in a large variety of sounds (mice, birds, cats, people, etc.). Does it need just a new set of vocal cords and tongue, or is it more complicated than that?

Mind of the Raven by Bernd Heinrich mentions a raven which managed a very convincing imitation of an explosion. You might find something useful by looking into the vocal systems of crows and ravens, and perhaps parrots too. Unfortunately, my specialty is in physics and astrophysics, not biology.

[TheWombatOfDoom]

Originally Posted by Conners

I'm considering an animal that is able to copy what it hears, in a large variety of sounds (mice, birds, cats, people, etc.). Does it need just a new set of vocal cords and tongue, or is it more complicated than that?

Birds have a syrinx, which can in theory, mimic most sounds pretty well. Some don't have the range, but think about parrots and how they mimic. My dragons actually have Syrinx's, which is why they are able to communicate in their own private languages, as well as in other languages as well.

Originally Posted by Tirunedeth

Planet stuff

Indeed it is a fantasy setting, with science fiction being part of it in terms of figuring out world creation. This system i've described is actually the Sirius start A and B, sans the planets of course. As for Termin, the planet thought to be a moon, if it's always between the sun and Aldain, how do people see it at night? There's no light illuminating it then either, is there? I'm thinking I'll do fudge-stronomy to say that the planet holds that orbit due to an interaction between it and Aldain, and it's slow rotation. It probably doesn't have much in the way of gravity due to it's slow rotation and damaged state. It's also keeping up with Aldain somehow, so that would make sense that it might be being "dragged" along by the other planets pull. Thought - could it not instead be at L2 and show all the time?

Horseshoe orbit weather reminds me of game of thrones weather. I wonder if that's intentional....

[Conners]

OMG, the videos of the Lyre bird are amazing !!!

Syrinx.. will look that up.

Thank you all .

[Ksheep]

Originally Posted by TheWombatOfDoom

Indeed it is a fantasy setting, with science fiction being part of it in terms of figuring out world creation. This system i've described is actually the Sirius start A and B, sans the planets of course. As for Termin, the planet thought to be a moon, if it's always between the sun and Aldain, how do people see it at night? There's no light illuminating it then either, is there? I'm thinking I'll do fudge-stronomy to say that the planet holds that orbit due to an interaction between it and Aldain, and it's slow rotation. It probably doesn't have much in the way of gravity due to it's slow rotation and damaged state. It's also keeping up with Aldain somehow, so that would make sense that it might be being "dragged" along by the other planets pull. Thought - could it not instead be at L2 and show all the time?

If the planet was at the L2 point of the gas giant, then it would always be in the shadow of the giant… a perpetual Solar Eclipse. However, since this is a binary system, you could potentially have some light periodically from one star or the other, but it would probably only get to the rim of the planet, so to speak.

As for what I said about the "moon" (gas giant) only being visible at night, you would basically have the moon in Full Moon stage all the time, with it reaching the highest point in the sky at midnight every night. To allow for it to have cycles, you'd have it in two different colors (or different albedos) on different hemispheres.

This is, of course, assuming that the axis of rotation is approaching 90º from the plane of the elliptic. If the axis was instead pointing approximately toward the sun/gas giant, than either the "northern" or "southern" hemisphere would be it constant day while the other was in constant night.

[Tirunedeth]

Originally Posted by TheWombatOfDoom

Indeed it is a fantasy setting, with science fiction being part of it in terms of figuring out world creation. This system i've described is actually the Sirius start A and B, sans the planets of course. As for Termin, the planet thought to be a moon, if it's always between the sun and Aldain, how do people see it at night? There's no light illuminating it then either, is there? I'm thinking I'll do fudge-stronomy to say that the planet holds that orbit due to an interaction between it and Aldain, and it's slow rotation. It probably doesn't have much in the way of gravity due to it's slow rotation and damaged state. It's also keeping up with Aldain somehow, so that would make sense that it might be being "dragged" along by the other planets pull. Thought - could it not instead be at L2 and show all the time?

Horseshoe orbit weather reminds me of game of thrones weather. I wonder if that's intentional....

I think the idea was that Termin is a fairly large planet (say, 5 times Earth's mass), while Aldain sits in Termin's L1 point. Actually, Aldain would probably follow a Lissajous or Halo orbit, which are in essence orbits around the L1 point. These are slightly more stable than simply sitting at the L1 point, although still unstable long-term. So Aldain would always be on the lit side of Termin, and Termin would slowly rotate and show "phases" due to its different hemispheres.

Also, gravity is based purely on mass. Slow rotation wouldn't cause a planet's gravity to be lower. Not to mention Termin's gravity is essential to the presence of the L1 point. The Sirius-Termin L1 point is where the combination of Sirius and Termin's gravitational pulls combine to produce a net acceleration which is just that needed to make an object sitting there orbit with the same period as Termin.

Hmm. I'm not entirely sure the Sirius system is going to work very well. Since Sirius A is 25.4 times more luminous than the Sun, its habitable zone is about 5 AU away. Sirius B is about as massive as the Sun, and has a very eccentric orbit which brings it as close as 7 AU from Sirius A. I'm not sure you could have a stable orbit that close to Sirius B. Still, maybe it's best to, as you say, use "fudge-stronamy."

I just remembered a website which could be useful for a lot of people: world-builders.org has a lot of information on things like orbital mechanics, geology, and biology which might be of use to people in this thread.

[Conners]

Is it possible to get jungles without a very hot, constant climate?

[Ksheep]

Originally Posted by Conners

Is it possible to get jungles without a very hot, constant climate?

That depends on what you consider to be "jungle". If you are referring to Rain Forest, then yes, there are temperate rain forests, most notably in the Pacific Northwest (Oregon, Washington, British Columbia), the west coast of Ireland, parts of Norway, and other such areas. However, if you take jungle to mean "the densest, most impenetrable region within a tropical rainforest with an abundance of animal and plant life", then by definition no: it would have to be a tropical rainforest to be such. However, if you follow the word back to it's Sanskrit root, jangala, then it simply means uncultivated land, and it originally referred to dry, uncultivated land. The problem lies in how you define a jungle, as unlike rain forest, it isn't well defined and it's meaning can vary from region to region.

Then, you have Upton Sinclair's definition, which was a turn-of-the-century American city, mostly centered around the poor immigrant parts of the city. This in turn leads to the Urban Jungle, which does not need to be a very hot climate, but it is usually rather constant in other variables, such as congestion, smog, noise, and violence.

[TheWombatOfDoom]

Originally Posted by Tirunedeth

Hmm. I'm not entirely sure the Sirius system is going to work very well. Since Sirius A is 25.4 times more luminous than the Sun, its habitable zone is about 5 AU away. Sirius B is about as massive as the Sun, and has a very eccentric orbit which brings it as close as 7 AU from Sirius A. I'm not sure you could have a stable orbit that close to Sirius B. Still, maybe it's best to, as you say, use "fudge-stronamy."

Fudge-stronomy. :) Just a basis, not exact.

[Conners]

Why is it that some creatures have amazing bacteria tolerance/immunity compared to humans? Some can eat rotting meat, etc..

Are there any complications in having a human-like creature with extreme disease tolerance (like goblins and stuff)?

[Spiryt]

Originally Posted by Conners

Why is it that some creatures have amazing bacteria tolerance/immunity compared to humans? Some can eat rotting meat, etc..

Humans can eat some relatively fresh meat, fruit, eggs, chocolate and so many other things that in one way or another will be toxic to some animals....

It's all the matter of adaptation to certain place in food chain.

[awa]

basicaly every thing costs calories you want a long digestive track able to handle particulary tough foods it cost calories, want a big brain it costs lots and lots of calories for humans having a big brain is more useful then having a strong stomach particularly becuase we can cheat and cook our food.

[TheWombatOfDoom]

Welp, even with fudging, its unlikely I'll find a binary system and a life zone to coincide. :( Back to one sun for me, it seems.

[jseah]

So, why is it that when it involves astronomy, worldbuilding in a consistent fashion is perfectly fine:

Spoiler

Originally Posted by Tirunedeth

I've taken more of a look at the horseshoe orbits, and I've run across a few problems for them. First, the longer their period, the farther the closest approach distance is. You're looking for both a long period and a short distance of closest approach, so that's going to cause problems. Second, the horseshoe orbits involve changes to the orbital radius of the planet. That's going to cause shifts in climate after each close approach to the gas giant.

Originally Posted by Tirunedeth

Hmm. I'm not entirely sure the Sirius system is going to work very well. Since Sirius A is 25.4 times more luminous than the Sun, its habitable zone is about 5 AU away. Sirius B is about as massive as the Sun, and has a very eccentric orbit which brings it as close as 7 AU from Sirius A. I'm not sure you could have a stable orbit that close to Sirius B.

Originally Posted by TheWombatOfDoom

Welp, even with fudging, its unlikely I'll find a binary system and a life zone to coincide. :( Back to one planet for me, it seems.

But the moment you involve math, people just go "eh, handwave it"??

Spoiler

Originally Posted by jseah

I would like to ask if this does what I think it does?
IE. is it true that one cannot rotate in a space where distances are calculated via manhattan distance instead of pythagoras?

Originally Posted by Yora

Unless your players are quantum physicists: yes.

Because then they'll almost certainly have not the slightest clue what either variant is and how they are different. A mage snaps his finger, it makes *poff* and something appears somewhere else.

=(

I say! This is discrimination against the abstract subjects!

...
So, for an actual world building question.
I have a theocracy as the leading power in one of my settings and would like to ask,
Given that the religion hates abstract thought and automation of magic (at the level of skinning you alive, publicly), how far can you get in technological innovation if no one thinks in abstract terms simply because it isn't taught anymore.
Practical thought: "If I have ten apples more than Bob, and we have 21 apples in total, how many do I have?"
Abstract thought: "X + 10 = 21; solve for X"

Obviously, the church can't mind control people and they're not actually big on thought police, so there will be independent inventions of it, but no written texts and the knowledge cannot be passed on (except maybe parent to child).

[TheWombatOfDoom]

Originally Posted by jseah

So, why is it that when it involves astronomy, worldbuilding in a consistent fashion is perfectly fine, but the moment you involve math, people just go "eh, handwave it"??
=(

I say! This is discrimination against the abstract subjects!

I certainly am not the greatest at math. In the astronomy department, I only just barely get by based on models where I only have to put in numbers. I used to be fairly decent, but I never learned more than algebra in school... and that was 8 years ago.

Given that the religion hates abstract thought and automation of magic (at the level of skinning you alive, publicly), how far can you get in technological innovation if no one thinks in abstract terms simply because it isn't taught anymore.
Practical thought: "If I have ten apples more than Bob, and we have 21 apples in total, how many do I have?"
Abstract thought: "X + 10 = 21; solve for X"

That severely depends on how they regulate it, and what they call abstract thought...sounds like written out math is out, and sciences. Does this mean calenders are out? Or more abstract than that? Honestly, I don't think its a seperate entity. People can easily come to that conclusion from one to the other, without writing it down. In fact, the practical thought is in actuality the abstract one. Someone thought up these things at some point - and it can be thought of again. And once you realize something, it affects your thoughts in inpercievable ways. The only way they could regulate any of that is written equations, or technology based on that, like calculators, and so on. Word of mouth is more powerful than you think. The complete text of the first 5 chapters of the bible were passed down through story telling. Why can't it be the same with math?