Basic Fantasy RPG Forums

Hello again,
A couple of years ago I was workling on dragonsfoot at a Spelljammerish setting supplement for BFRPG
(http://www.dragonsfoot.org/forums/viewt ... 42&t=38683).

The file is currently on my website ( http://artikid.altervista.org/?id=Games ... idspanners), would the community be interested in cleaned-up and updated version to be hosted here?

Cheers
Artikid

PS: last post for today, promise

Are you reading my mind? I have been toying with this off and on. I did download your stuff a while back. I will have a look again and see. Now that the lich is done, 'skyships' might as well be next on my hit list.

Hi Artkid

I like the idea but I am a little confused, why Tellus has a rotation and revolution period if it's the center of everything?

To be honest I would keep the big fiery ball at the center of the system as it leaves much more spaces to move, you could just say that to leave for the star the voidship are not yet ready (you need some new spell or enchantment).

ps: I have just skimmed through it sorry

Fabio_MP wrote:Hi Artkid

I like the idea but I am a little confused, why Tellus has a rotation and revolution period if it's the center of everything?

To be honest I would keep the big fiery ball at the center of the system as it leaves much more spaces to move, you could just say that to leave for the star the voidship are not yet ready (you need some new spell or enchantment).

ps: I have just skimmed through it sorry

Rotation and revolution for Tellus are an error.
Sorry but Tellus is staying at the center of the system, just like earth did in the days of Ptolemaic astronomy.

ante scriptum: I love what you have done but I need some clarification (sorry if I sound harsh)

artikid wrote: Sorry but Tellus is staying at the center of the system, just like earth did in the days of Ptolemaic astronomy.

well actually this is not sure, the Ptolemaic system was the reification of a calculus system http://en.wikipedia.org/wiki/Lucio_Russo

anyhow if the center of the world is Tellus what is the meaning of rotation and revolution of other bodies? Since they have no relation with the "sun" what we get by the rotation e revolution periods?

EDIT: I got a few ideas see next post

the Earth centered system didn't need to calculate days and years on other planets just where they would appear in the night-sky during the year.... it would be easier to say that this other planets have their own seasons and day-time) or light source or whatever works

ps: I'll add
1) this very useful link: http://en.wikipedia.org/wiki/Extraterrestrial_skies
2) this very nice diagram

Ok I thought about it

I still think that the Ptolemaic system is hard to salvage (and give more problems than advantage) but here are a few hints:

anyhow you still need tellus rotation time and rotation of other planets (revolution could be a problem let see some solution); most of the problem are with distance from the sun duration of the year and seasons (or if you prefer the problem is that you have to find the relative position of the sun to the various planets)

1) rotation of tellus will tell us how long is the day
2) revolution can be the revolution of the sun around tellus

if the revolution of the sun is different from that of other planets that means that other planets get wild variation in the sun size in their sky; I'll try to analyze this with ASCII graphic
T: tellus; M: moon; S: sun; I: ivoreze

1st situation every planet is on one side of Tellus:
_-_-_-_-_-_-_-_-_-_T_-_-_-_M_-_-_-_-_-_-_-_S_-_-_-_-_-_-_-_-_-_I

2nd situation Ivoreze is on the opposite site of the Sun (that is much smaller than our sun so to have I on the other side is a big problem for I, which is the nearest one; the other planets would have it so much worse):
I_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_T_-_-_-_M_-_-_-_-_-_-_-_S

A possible solution could be that the revolution around T is the same for the Sun and every other planet so they are always on the same side of T and so their relative distance is always the same (and we don't care if external planet have to run much more) actually you could also them fixed in the sky....)

still I think that an heliocentric system is sooo much simpler and easy to think about

Fabio
I now understood the nature of the "problems" you are pointing out.

Fabio_MP wrote: I still think that the Ptolemaic system is hard to salvage (and give more problems than advantage)...most of the problem are with distance from the sun duration of the year and seasons (or if you prefer the problem is that you have to find the relative position of the sun to the various planets)....other planets get wild variation in the sun size in their sky

I dare say it is in your POV, you are looking for scientific answers/coherence.
I dare take a guess that you are a math/physics teacher or work in scientific research probably.
Most people would not understand what you are talking about, and I think even less would care.

As things stand VS has been out on the net for 4 years (with 1042 views on dragonsfoot and I don't know how many downloads from my site) and you are the first poster to make this type of suggestion.

When I wrote Voidspanners I thought: "Let's kill science with a wet sock, I want to write a planetary system that gets everything intentionally wrong. Sue me."

Days and seasons exist as they do in the Voidspanners planetary system because that's what I say, not because it is more logical or "right".
I wrote Voidspanners because magical flying ships and fantasy space pirates are cool.

So that's why Tellus will remain at the centre of the system with the other plantes revolving around it.

artikid wrote:Fabio
I now understood the nature of the "problems" you are pointing out.

I dare say it is in your POV, you are looking for scientific answers/coherence.
I dare take a guess that you are a math/physics teacher or work in scientific research probably.

indeed I am

but the point is _internal_ coherence

Most people would not understand what you are talking about, and I think even less would care.

this is a pity, and more their loss than mine

As things stand VS has been out on the net for 4 years (with 1042 views on dragonsfoot and I don't know how many downloads from my site) and you are the first poster to make this type of suggestion.

yes I tend to nitpick on this thing as I am quite versed in both Ptolemaic and Real physics and how they correlate with each other

OTOH maybe people just cannibalized what they liked and killed the Ptolemaic thing in the cradle

When I wrote Voidspanners I thought: "Let's kill science with a wet sock, I want to write a planetary system that gets everything intentionally wrong. Sue me."

this is not a big problem as long as everything works
I remember that in spelljammer there where crystal spheres and one they visited on some of the novels had an internal sun and all the sphere covered with continents and whatever

Days and seasons exist as they do in the Voidspanners planetary system because that's what I say, not because it is more logical or "right".
I wrote Voidspanners because magical flying ships and fantasy space pirates are cool.

So that's why Tellus will remain at the centre of the system with the other plantes revolving around it.

this is OK, BUT

1) instead of rotation/revolution period you should give day/year/season/temperature much more useful

2) you should at least describe WHAT people see in the sky on each different planes/planets (as you did explaoining what happens in going from one sphere to the other ) question to be answered:
they see the sun? how much big?
they see tellus? how much big?
they see the other planets? in particular the first four how they see each other?
and from the moon what do you see (these is the easiest as it is as in our world)?

you can even just say that on Ivoreeze you never see the sun but just an hazy light that cover all the land in an eternal dusk IT'S OK but I cannot get it from rotation/revolution periods...

Fabio_MP wrote: 1) instead of rotation/revolution period you should give day/year/season/temperature much more useful

2) you should at least describe WHAT people see in the sky on each different planes/planets (as you did explaoining what happens in going from one sphere to the other ) question to be answered:
they see the sun? how much big?
they see tellus? how much big?
they see the other planets? in particular the first four how they see each other?
and from the moon what do you see (these is the easiest as it is as in our world)?

you can even just say that on Ivoreeze you never see the sun but just an hazy light that cover all the land in an eternal dusk IT'S OK but I cannot get it from rotation/revolution periods...

This I can totaly agree with

artikid wrote:
This I can totaly agree with

and this is what I was trying to say from the start

maybe I was just a little too much long-winded