now, for many types of propulsion, they explicitly don't allow you to take off from planets above size A (i assume this has more to do with momentum and distance involved to escape gravity rather than gravitational strength, since spelljammer primarily uses a binary gravity system).
in any event, if you have a planet where the gravity plane does have a point where it reverses direction (akin to the way a ship's gravity plane works) i can't think of a reason you couldn't escape the planet's gravity well by flying along the gravity plane itself. (in fact, technically, over the course of a rather long time, you will eventually be pushed out of the air envelope simply by floating on the gravity plane at all).
just checking to see if anyone disagrees, and if so why.
I think a body floating on the gravity plane of a flatworld should go toward the middle, non toward wildspace. Should it go toward wildspace, the flatworld would lose some terrain to wildspace each year and extinguish itself in time...
according to how gravity planes work, it goes out though. presumably this is why flatworlds often have mountains ringing them... generally speaking, it's not a strong enough force to rip rock apart =P (it also does a good job of holding in water, if there is any).
regardless, it isn't a very strong force, so either way the weak propulsion systems should still be able to escape the planets air envelope, right?
From "Pratical planetology", page 47, about Plata (a flatworld) gravity plane:
"Any object or creature which falls over the the edge drops to the gravity plane and remains there. There is a gentle force that pushes such an object outward along the gravity plane. [...] 50 miles out from the edge of the disk, the object falls free into the vacuum of Wildspace".
Anyway... i think that this is the case of Plata only. It seems more logical that the gentle force it toward the flatworld, not outward!
of course, this brings up the question: how come the air doesn't all gradually leave?
(for the record, i think the answer is "because TSR said so")
Anyway... i think that this is the case of Plata only. It seems more logical that the gentle force it toward the flatworld, not outward!
No. Jaid is right. This is the way that all gravity planes work. If gravity drift didn't slowly make objects float away from a ship it would end up with a tidemark of random rubbish hugging the ship on the line where it bisects the gravity plane. Somoene would have to collect it and get rid of it.
If gravity drift didn't slowly make objects float away from a ship it would end up with a tidemark of random rubbish hugging the ship on the line where it bisects the gravity plane. Somoene would have to collect it and get rid of it.
Taht would be a great idea to always have a kender onboard! ;)
Seriously: with a ship your elucubration is correct, but a flat-world would eventually dissolve in wildspace.
Let's say: real world gravity is toward the center. But there is no spaceborn random rubbish hugging on planetary sudrface!
So, there would be none either in SJ fantasy space and in ships gravity plane!
Let's say: real world gravity is toward the center. But there is no spaceborn random rubbish hugging on planetary sudrface!
That's because most of it gets burned up in the atmosphere.
I do like the idea of spelljammer crews having to periodically clean up flotsam attracted by the ship's gravity.
Wyvern
Taht would be a great idea to always have a kender onboard! ;)
Seriously: with a ship your elucubration is correct, but a flat-world would eventually dissolve in wildspace.
Let's say: real world gravity is toward the center. But there is no spaceborn random rubbish hugging on planetary sudrface!
So, there would be none either in SJ fantasy space and in ships gravity plane!
It works because it's magic. No other reason needs to be there. Why does everyone want to use real world examples to explain something when thier are elves and dragons flying around in space? :D
It works because it's magic. No other reason needs to be there. Why does everyone want to use real world examples to explain something when thier are elves and dragons flying around in space? :D
This isn't about "real-world examples", it's about internal consistency. To wit: if objects in a gravity plane move outwards, how do flatworlds hold together? Just saying "It's magic!" isn't a very satisfactory answer. Some of us like to think about these things. (And if you don't, feel free not to post in this thread.)
Wyvern
This isn't about "real-world examples", it's about internal consistency. To wit: if objects in a gravity plane move outwards, how do flatworlds hold together?
sovereign glue? :D
or, more likely, they should generally be composed of one really really big rock (mountain range) surrounding any non-rock material.
I think this rule is useless and the wole Spelljammer system would be better if matter floating in a gravity plane will slowly go inside...
Why the rule that matter slowly floats away from the gravity plane was first introduced? What kind of consequences it has in the grand scheme of the things in Spelljammer? Could Spelljammer work without this rule?
a) I don't know.
b) I don't think the original authors really considered the consequences.
c) Absolutely.
I think this rule is useless and the wole Spelljammer system would be better if matter floating in a gravity plane will slowly go inside...
After reading this thread, I'm inclined to agree.
Wyvern
Some of us like to think about these things. (And if you don't, feel free not to post in this thread.)
It isn't really nice to invite someone to not post. Please don't be rude to people who disagree with you. Spelljammer needs all the support it can get and we need to keep people in the community. Sometimes a person who disagrees with you helps you to think, so they can often be more helpful than someone who shares your opinion.
I do like the idea of spelljammer crews having to periodically clean up flotsam attracted by the ship's gravity.
I think this rule is useless and the wole Spelljammer system would be better if matter floating in a gravity plane will slowly go inside...
Sadly for both of you, the Spelljammer designers had good reason to make things work the opposite way to what you desire. But if you want to get people to clean things off of the hull, don't forget that their are parasites that like to attach themselves to a ships hull as well as more dangerous creatures that might decide to swim along under the ship and wait for a chance to go topside and feed.
Why the rule that matter slowly floats away from the gravity plane was first introduced? What kind of consequences it has in the grand scheme of the things in Spelljammer? Could Spelljammer work without this rule?
a) I don't know.
b) I don't think the original authors really considered the consequences.
c) Absolutely.
a) If you don't know why they introduced the rule then you shouldn't really dismiss it until you think about why they might have done it.
b) What makes you think that the Spelljammer designers didn't consider the rule?
c) I think I might know why this rule was introduced and if I'm right then the rule is essential to gameplay.
OK. Lets compare two scenarios: Firstly a crewmember falling overboard and secondly someone dropping some goods overboard.
The crewmember vs normal Spelljammer gravity plane drift (outwards)
The person who falls overboard bobs about a bit, and starts to slowly move away from the ship. If they don't do anything they will fall out of the ships air envelope and be treated as a separate body. The ship will accelerate away from them and they will only have the air that they take with them. If they don't get rescued before their air runs out they will die. This creates peril for anyone who falls overboard and makes it essential to rescue crew members.
The crewmember vs non-standard gravity plane drift (inwards)
The person who falls overboard bobs about a bit, but starts to slowly move back towards the ship. If they don't do anything they eventually get back to the ship and can climb back onboard. Even if they fall while climbing back onboard their is absolutely no risk to them. They just drift back again and again.
Why normal gravity drift works well with crewmembers.
Spelljammer's outward gravity drift creates a risk to falling overboard. This is rather similar to the risk faced by people who fall overboard on real-life ships. Gravity drift is one of the background dangers that make wildspace travel feel realistic.
Goods overboard vs normal Spelljammer gravity plane drift (outwards)
Like the crewmember the goods bob up and down, and slowly drift outward. After leaving the ships air envelope the goods become flotsam and drift through wildspace until another ship blunders into them. At this point they can get picked up by the crew of the new ship. Flotsam (and jetsam) can be used as adventure hooks as a party can find something like a ships log, a letter or anthing else the DM wants to send their way.
Goods overboard vs non-standard gravity plane drift (inwards)
This time the goods bob up and down, but slowly drifts back in towards the ship. Eventually they reach the hull and just sit there. The goods are at no risk of getting lost unless the ship enters a larger gravity plane. In fact if the crew needed deck space they could throw the entire contents of the hold into the gravity plane and watch it surround the ship.
Why non-standard gravity drift works badly with goods.
Ignoring Spelljammers outward gravity drift drastically alters the cargo capacity of a ship. Throwing things overboard makes them all get towed along. The only limit to cargo "dragging" capacity would be the size of a ships air envelope. Backward gravity drift would also be usable in combat as ships could "drag" several tons of rocks towards the top of an asteroid like The Rock of Bral and then fly into its upper atmosphere to let Bral's larger gravity pull the rocks away.
In summary altering the gravity would lower the risk to ships crews, but raise the risk to inhabitants of small asteroids.
As for flatworlds somehow being ripped apart by gravity drift, I think you are forgetting the fact that gravity drift doesn't start until the body (flatworld, asteroid, ship or whatever) ends. There is no sideways force on objects that are still on the flatworld. A flatworld would only be at risk if the people living their threw all of their waste overboard instead of recycling it. Doing that would slowly destroy the eco-system as it would remove material that plants need to grow.
Why normal gravity drift works well with crewmembers.
That's a good explenation!
Whis way: gravity outward is a game necessity that has no fisical explanation.
Good.
But I like fisical explanations, also fantasy should have a "why" and it should be "not-character-centric" (in my humble opinion!).
So, now my question is only different, but I always have it: why gravity outward drifting starts at the ent of a gravity inducing body? Why isn't there an outward slow movement in the interior part of the gravity plane?
If you leave a marble, perfectly spherical, in the foor of a spelljamming sheep, it could stay still, or it could roll...
If gravity moves slowly toward wildspace... the marble should slowly roll outward the sheep.
Or... why does it not?
A river brings debrils toward the sea. And debrils accumulates at the end of the river and expand the land versus the sea. That's what happens in the real wolrd, and it's logical.
You said that a flatworld will never expire unless people trows waste in the space... I'm not sure. Wind will always bring some earth matter overboard, ant it will slowly bob outward... and the flatworld will eventually expire, also if inhabitants are not so stupid to trow waste in the space.
So I still have 2 points:
1) I can't see any reason the outward movement starts at the end of the body (being it a sheep or a flatworld).
2) A flatworld will eventually expire if gravity is outward.
Who can answer my points?
incidentally, something placed at the exact center of the flatworld would simply sit there... it's being pushed equally in all directions outward along the gravity plane, and therefore would not move. as far as the rest, well, like i said... most flatworlds seem to have walls of some kind or another on them (a mountain range, for example), or be made of one solid object (ie an asteroid). remember that only stuff *on* the gravity plane is effected. an object one foot above the gravity plane is simply pulled towards the gravity plane. so there's good reason to not expect loose material on the edge of the flatworld in question along the gravity plane, but material elsewhere simply goes towards the gravity plane, and is not moved outwards whatsoever.
* There is a slow drift towards the ship for all objects inside the air envelope. Any large body at rest will eventually have all nearby objects land on their surface. This also applies for any ship at tactical (ie encounter) speeds.
* Any time the ship moves at strategic spelljamming speeds, any object larger than a grain of dust and not physicaly in contact with the ship gets left behind.
* If an object loses contact with a ship whle at strategic spelljamming speeds, it stays with the ship only as long as the ship does not maneouver. if the ship maneouvers (changes speed or direction, or drops from strategic speed), the drifting body continues in a ballistic course, gradually slowing down. In all probability it will hit the crystal sphere or enter orbit around a planet before getting intercepted.
Thoughts?
while it's flavourwise necessary that falling overboard entail some risk, it is (imo) preferrable that it isn't an automatic death sentence. which, for the record, is what happens when you fall overboard at spelljamming speeds, or if your ship can't afford to continue flying in a straight line at a constant speed indefinitely.
if you must change things around, then simply assume that atmosphere (ie molecule sized objects) is the only thing that isn't pushed out at the gravity plane. or, instead, assume that there is a sort of gravity current around the edge of the air envelope, which does not have enough strength to move anything more dense than the atmosphere.
thus, you keep your atmosphere (along with anything equally or less dense than it, and any heavier gas which gets mixed in, thereby matching itself to the density of the atmosphere by increasing the density of the atmosphere it mixes with).
how does that sound? it also makes air circulation a built-in feature of the air envelope (which is good, imo)
It isn't really nice to invite someone to not post. Please don't be rude to people who disagree with you. Spelljammer needs all the support it can get and we need to keep people in the community. Sometimes a person who disagrees with you helps you to think, so they can often be more helpful than someone who shares your opinion.
Disagreement isn't the issue here. If he'd said "I think the original rule makes more sense/is more interesting, and here's why," I would have been fine with that. However, what he seemed to me to be saying was, "Anyone who cares about those sorts of things is thinking too hard." He's perfectly entitled to that opinion, of course, but I wish he would refrain from expressing it in a thread which is all about discussing "those sorts of things". It's not very nice, and it doesn't help people to think, and I reacted accordingly. I admit that tact is not one of my strengths, and I can be a bit harsh when I'm annoyed by other people's rudeness, but I tried to make it clear that my meaning was not "Buzz off, we don't care what you think," but rather "If you don't have anything constructive to add to the thread, why are you posting in it?"
a) If you don't know why they introduced the rule then you shouldn't really dismiss it until you think about why they might have done it.
b) What makes you think that the Spelljammer designers didn't consider the rule?
I never suggested that they didn't "consider" the rule, I only said that I don't think they considered all the consequences (specifically with regard to flatworlds).
As for flatworlds somehow being ripped apart by gravity drift, I think you are forgetting the fact that gravity drift doesn't start until the body (flatworld, asteroid, ship or whatever) ends. There is no sideways force on objects that are still on the flatworld. A flatworld would only be at risk if the people living their threw all of their waste overboard instead of recycling it. Doing that would slowly destroy the eco-system as it would remove material that plants need to grow.
The crucial issue is how you define being "on" the flatworld. If water flows off the edge of the world, what happens to it? What if there's a landslide? What if I stand too close to the edge of the cliff and cause a bit of it to crumble and fall off?
sure, flatworlds might constantly toss stuff out naturally. but then again, there's gonna be space dust and whatnot coming in from the top and bottom of the world, naturally (possibly from other flatworlds :P)
Now that's an interesting idea.
Wyvern
assume that there is a sort of gravity current around the edge of the air envelope, which does not have enough strength to move anything more dense than the atmosphere.
thus, you keep your atmosphere (along with anything equally or less dense than it, and any heavier gas which gets mixed in, thereby matching itself to the density of the atmosphere by increasing the density of the atmosphere it mixes with).
I like this idea! Also assume dust (earth) and vapor (water) will move with air around the atmosphere.
So we have air, earth and water moving around a flatworld. Shou sages say that also pollen is an elemental thing moving in the atmospheric current, for their 5 elemental theory.
Interesting...
I don't see any drawback in game mechanics.
It should work on ships too.
It should work on sheeps too.
You mean ships. Sheep = pecore. (No, I don't speak Italian; I went to Babelfish for the translation.) I normally don't bother correcting people's English on message boards, but the thought of spelljamming sheep is pretty comical. :D
Wyvern
I'm sorry that reading it in a forum I can't hear the difference between the two...
(by the way: we have flying squids, nautiluses, shou dragons, mantarays, spiders, butterflies (ok, butterflies are not so strange), eels, skorpions, dolphins, swans (swans too are not that strange), werewolves... why should we disregard a flying sheep? :P )
You know... it is my fault: I always miss ship and sheep... I think I have a defect of prununciation, ant the 2 are the same for me...
I'm sorry that reading it in a forum I can't hear the difference between the two...
(by the way: we have flying squids, nautiluses, shou dragons, mantarays, spiders, butterflies (ok, butterflies are not so strange), eels, skorpions, dolphins, swans (swans too are not that strange), werewolves... why should we disregard a flying sheep? :p )
because, if there's one thing i've learned from Worms, it's that sheep are deadly weapons, highly unstable, unpredictable, and really wouldn't be safe to have around in the phlogiston.
if there's one thing i've learned from Worms, it's that sheep are deadly weapons, highly unstable, unpredictable, and really wouldn't be safe to have around in the phlogiston.
LOL
So, extend this to a flat world. Anything that falls "over the edge" also gradually drifts out to space. But there's no force tearing away at the edge of the flatworld, just like there's no force slowly dissolving a ship.
And the flatworld has an atmospheric envelope just like a ship does, so that's why the air stays in.
Why would a flatworld dissolve? The rule says that anything that "falls overboard" (i.e. off the side of the ship into empty space) gradually drifts away from the ship.
So, extend this to a flat world. Anything that falls "over the edge" also gradually drifts out to space. But there's no force tearing away at the edge of the flatworld, just like there's no force slowly dissolving a ship.
And the flatworld has an atmospheric envelope just like a ship does, so that's why the air stays in.
Sorry but...no!
I disagree with you: wind and atmospheric agents will slowly erode the flatworld and eventually dissolve it with outward gravity. Just as a river erodes a mountain and expands the beach near the sea.
But with Jaid idea of the atmospheric current (the base for a Jaid's law!) it seems to work fine.
because, if there's one thing i've learned from Worms, it's that sheep are deadly weapons, highly unstable, unpredictable, and really wouldn't be safe to have around in the phlogiston.
Worms?
So, extend this to a flat world. Anything that falls "over the edge" also gradually drifts out to space. But there's no force tearing away at the edge of the flatworld, just like there's no force slowly dissolving a ship.
As I said in my earlier post:
The crucial issue is how you define being "on" the flatworld. If water flows off the edge of the world, what happens to it? What if there's a landslide? What if I stand too close to the edge of the cliff and cause a bit of it to crumble and fall off?
Wyvern
Worms?
Age of Worms, perhaps?
everyone gets to take turns, and on your turn you have a selection of weapons you can use to try and kill the other teams... ranging from fairly standard weapons (Uzi, bazooka, grenades) to really weird, random stuff... like exploding sheep that jump around randomly, carpet bombs (a plane flies over, drops a carpet which unrolls over an area, dealing damage), physical attacks (great for knocking people off the map ;) ) kamikaze (the worm launches themselves across the screen, knocking stuff out of the way... the worm who uses the attack just keeps going off the screen, but may at least end up killing another worm, if you're lucky) and other stuff.
sheep show up a lot in worms, and in all forms are highly explosive, prone to blowing up at the slightest provocation. they are also not controllable once 'fired'.
as you can imagine, bringing one of those sheep into the phlogiston would be a bad idea...
anyways, if you have easy access to a gaming system that you can play worms on, i highly recommend it, if you can get a group of 4 friends around. it's really fun ;) (might make for some good stress relief if you take breaks during gaming sessions... might also take over a gaming session though).
don't like it, personally.
I don't like it either. I prefer to stick to the core rules of Spelljammer unless someone can prove to my satisfaction that they do not work (or do not work with 3e). In this case I'm happy that the flatworld concept is a sound one.
while it's flavourwise necessary that falling overboard entail some risk, it is (imo) preferrable that it isn't an automatic death sentence. which, for the record, is what happens when you fall overboard at spelljamming speeds, or if your ship can't afford to continue flying in a straight line at a constant speed indefinitely.
I disagree. I don't think there is an automatic death sentence if you fall of a ship at spelljamming speed. (Firstly I'd like to point out that a crewman is less than 10 tons so will not cause the ship to automatically drop to tactical speed - this means the helmsman will not notice.)
The crewman will slowly drift away from the ship and will eventually leave the air envelope. However page 13 of the CoAS also states "A ship's air envelope does not turn with the ship when it turns, but objects in the ship's air envelope do not drift towards the rear of the ship simply because the ship is moving forward."
This means that regardless of the speed a ship is travelling at the falling crewman will always drift out slowly towards the edge of the air envelope. They will carry on moving at the same speed as the ship as long as they can stay within its air envelope. They will always get the same amount of time to yell for help. If they don't want to yell they can start taking off their gear and throwing it away from the ship - this will push them back towards the ship and give them a chance to grab hold of something on the ship's gravity plane.
IMO: Only falling off of a ship that is in the upper atmosphere of a planet is an almost certain death sentence. I'd say you get a reflex saving throw to catch anything sticking out of the side of the ship, but then are on your own.
Disagreement isn't the issue here. If he'd said "I think the original rule makes more sense/is more interesting, and here's why," I would have been fine with that. However, what he seemed to me to be saying was, "Anyone who cares about those sorts of things is thinking too hard."
Fair enough, but if he wasn't getting his message across properly and didn't mean "you are thinking too hard" he might not come back and explain what he did mean. This might have just been his "initial gut reaction" and he might have brought something really useful to the table in his second or third post. Still never mind - what is done is done.
I never suggested that they didn't "consider" the rule, I only said that I don't think they considered all the consequences (specifically with regard to flatworlds).
I've seen a number of conversations where scientific examination is applied to the workings of the Spelljammer setting and it always seems to pull apart under scientific examination.
This sort of discussion is interesting, but I think that we need to look at SJ with the eye of a philosopher and assume that SJ works. If we do that then we can say: "I know that flatworlds do not break apart, so what sort of force would explain why they stay together?"
That seems to be what Jaid has done here (with the "space dust") so even though I disagree with your views, I think this conversation has taught me something useful. (That is why I say it is always good to talk to people who you don't agree with. I don't think I'd have thought of that if I wasn't part of this discussion.)
The crucial issue is how you define being "on" the flatworld. If water flows off the edge of the world, what happens to it? What if there's a landslide? What if I stand too close to the edge of the cliff and cause a bit of it to crumble and fall off?
Existing flatworlds (and ribbonworlds which also would suffer from a similar problem) seem to have mountains placed around their edges. These make flatworlds act a bit like a bowl, so as gravity pulls things down the angle of the mountains pushes them inward.
In that context their is no problem with flatworlds, but I suppose you could create one that would break up if people kicked at its edges and cliffs.
I could say that the flatworlds we have now are the ones that were built to stand the erosion of time and that wildspace dust (as well as passing flotsam and jetsam) would replace any lost mass.
However, I think I'd prefer to say that this logic only applies for those flatworlds that are documented in cannon SJ material and that you are free to build your own flatworlds that suffer from erosion. However, if you do want to do that I think you should also create some sort of thing that creates (or used to create) new flatworlds (otherwise there will be no logical reason for any unstable flatworlds to exist).
why should we disregard a flying sheep? :P )
Sometimes a great idea comes along accidentally.
You could perhaps find or create a nomadic race of passive vegetarians who fly around asteroid belts looking for plants to eat. They could live in gigantic communities (herds) that are so large that it is impossible to get everyone onboard one ship.
So they could develop (or buy from the arcane) a type of spelljamming helm that makes one ship follow another ship. The most powerful helmsman in the community could then fly a "Ram Ship" while everyone else followed along in their "Sheep Ships".
As sheep are sometimes associated with dreaming, you could even allow spellcasters on the "Sheep Helms" to sleep while spelljamming. This would allow them to spelljam for extreme time periods without suffering from the sort of fatigue that alert helmsmen eventually get.
I disagree. I don't think there is an automatic death sentence if you fall of a ship at spelljamming speed. (Firstly I'd like to point out that a crewman is less than 10 tons so will not cause the ship to automatically drop to tactical speed - this means the helmsman will not notice.)
For clarification, this was operating under the assumption that we used his revised suggestions. i believe it came from a misreading on my part; i saw "spelljamming speeds", which i associate with the travel speed, when he said "strategic spelljamming speeds" (which i generally refer to as simply tactical speed). if you read his suggestion above that post, you will note that it appears that falling off the ship while it is travelling at spelljamming speed, they either drop out of spelljamming speeds (and are pretty much permanently lost) or are launched either into space as soon as the ship moves in anything that is not a perfectly straight line (or into the ship), turning them into a high speed projectile flying through space... until they hit something and die. in point of fact, his system doesn't seem to indicate at all what happens if the ship is travelling at spelljamming speeds, so who knows what happens in his proposed system.
Sometimes a great idea comes along accidentally.
You could perhaps find or create a nomadic race of passive vegetarians who fly around asteroid belts looking for plants to eat. They could live in gigantic communities (herds) that are so large that it is impossible to get everyone onboard one ship.
So they could develop (or buy from the arcane) a type of spelljamming helm that makes one ship follow another ship. The most powerful helmsman in the community could then fly a "Ram Ship" while everyone else followed along in their "Sheep Ships".
As sheep are sometimes associated with dreaming, you could even allow spellcasters on the "Sheep Helms" to sleep while spelljamming. This would allow them to spelljam for extreme time periods without suffering from the sort of fatigue that alert helmsmen eventually get.
well, this is a kind of interesting idea... might be interesting to stat up sometime.