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Proof-reading EG
XYZ coordinates are probably the easiest to grok, since they can be translated directly onto a flat top-down map. The third component, the 'z' axis, can be represented on the label for each location, as in 'Jilunan, 405 ly above galactic plane' or the like.
I'm thinking in terms of several different coordinate systems, each of which has its good and bad points, but I think I prefer named sectors tiling the sky as seen from Earth, along with a distance in light years.

This is an Earth-centric polar coordinate system but without right-ascension/declination numbers. One could be relatively precise and say something like "Libra Sector 4A 378", where Libra Sector is a subsection of sky which probably includes most of the constellation Libra or is at least close to it, but it's the same size and shape the same as all the other named subsections of sky. 4A would localize it further, picking out one of several hundred subsectors, and 378 would be the distance from Earth in Light years. Or you could be less precise and give the name of the larger volume it's in, such as "Libra 350," Tagging a much larger general neighborhood which it may share with some other things (with distances in multiples of 50 ly).

Of course sectors like that would be a lot wider the further away from Earth you get, for the same reason that longitude/latitude graticules on Earth are wider near the equator than at the poles. Out at the edges of Terragen space you'd probably have to use another subsector division to be precise. And the major problem with a polar coordinate system is that it isn't dead-simple to calculate distance the way it is with Cartesian coordinates; one can't just use the Generalized Pythagorean formula, but instead has to do trigonometric things that require thinking. Or, you know, a snip of code.

I like the Earth-central polar coordinate/sector system, I think, because the distance from Earth is a pretty strong immediate indicator of how recently colonized and how 'civilized' it is and whether it's in the wormhole nexus and so on. Adopting a coordinate system where that's one of the most prominent features of a location makes it easier to immediately understand what *kind* of place we're talking about just from the coordinates, and it gives large volumes nice succinct tags which are primarily linguistic rather than numeric and as such easier to remember. Also, I just like the sound of sectors named after constellations.

The succinct coordinates of some areas can become infamous in their own right; people will know what sector/distance is the Laughter Hegemony or the Verifex Volume, and, very importantly, can easily recognize coordinates that are "close to" those places.
I suppose this kind of thing would work, although I'd prefer the more precise option you mentioned first. There is the obvious question of why cultures hundreds or thousands of ly away from Earth would be referencing off of constellations that are only really visible in the night sky of Earth or it's closest neighbors, but we can probably come up with some explanation for that along the same lines of what we have for the After Tranquility dating system.

Four thoughts that come to mind on this:

a) We already have a mention of some number of sectors being in play in the Regions of Space article - we might see if we can make those fit with this system (or whatever system we ultimately come up with). Or we will want to modify the relevant article(s) to fit the new system.

b) How might we present this visually to help readers start to get a gut feel for where things are just from their given coordinates?

c) Which constellations would be used and how sectors would be needed?

d) How would the 'secondary' sector system used further out work and be represented? It should tie back to the central sector system in a way that is again easily visualized by the audience - so that a set of coordinates for someplace thousands of ly away is as easy to visualize as one 10ly away.

Finally, and coming at this from another direction - would it perhaps be easier to use some kind of sector addressing system based on XYZ coordinates and distance? Our current maps already have a grid overlay on them that might form the basis for something like this. It might be doable to also reference constellation names in this system as well and use numbering or coordinates to get pretty precise locations for each system or other place.


A coordinate system with its origin at the Galactic Center, its X-axis aligned with the Galactic Bar, and its Y-axis perpendicular to the X-axis. The Z-axis could be the distance above/below the mid-plane of the Galactic Disc. Units could be in parsecs (and multiples thereof). This could replace the heliocentric equatorial coordinate system now in use with a naturally derived galactocentric Cartesian (XYZ) system; the position of Sol, for example, is about 20 degrees off-axis in the Gamma Quadrant (about 8000 parsecs from the origin) and perhaps 20 parsecs above the mid-plane. The viewpoint of the grid would need to be specified, whether from above (North) or below (South) the Galactic Center, as the quadrant designations are not identical.

Just a stray thought,

"I'd much rather see you on my side, than scattered into... atoms." Ming the Merciless, Ruler of the Universe
I have considered the Galactic Centre system, but since most of the galaxy is not included in the Terragen Sphere, I think that the best and most intuitive one is the Sun-centred Galactic XYZ system of coordinates. I've got lots of XYZ data in this system available, and can calculate more - if you want to want to convert it to Galactic Centre coordinates simply add 25,000 to the X-value and 70 from the Z value..

We also include the 'constellation-as-seen-from-Earth' in most descriptions - this can be extended to all descriptions without too much bother, and we could even include the RA and Dec in the equatorial system since this is the most widely used astronomical system. Practically every description of a location in OA includes the distance from Sol as well, and this should continue.
"constellations" or sectors are a shorthand for right ascension/declination, but denote regions instead of exact angles. And I think that vagueness is important.

As a fiction writer, I pin down locations loosely to allow for later detailing. - I mention the town of Lost Mesa Nevada, and Nevada is a big damn place but that's specific enough for that little fictional town. If someone is later doing a map of our fictional Nevada and thrashing details, I want them to be able to search for the name of Nevada and discover that a little town named Lost Mesa is supposed to be somewhere in it. Then they should still be free to give Lost Mesa a specific location that's plausible relative to all the other things that are supposed to happen to or be in our fictional Nevada - you know, giving it coordinates outside of the coordinates we're assigning to the Los Alamos testing range and Area 51 and so on.

If I'm forced to give full numeric coordinates for the location of Lost Mesa at the outset, then there's no room for later detail resolution; I have to get it right the first time and then everybody else has to get everything else right to avoid putting their area 51 at the same location, etc. And anyway coordinates, however useful they are for calculation, aren't the way people think of locations.

So I'm looking for an analogue to that symbolic knowledge or deliberate vagueness; a way of having short semi-symbolic names for large volumes that are related to each other in some way that's orderly and defines general regions of terragen space relative to each other, but without requiring people to pin it down exactly or remember long strings of numbers. The long string of numbers is for when the place gets busy enough that details need to be thrashed to avoid inconsistency, or for when the place gets interesting enough that someone wants to do a regional map. But people want a more relatable system for saying what region they want to look in, and writers want the ability to be deliberately vague and thrash details later without doing rewrites.

So I'm thinking of a system where I can say that something is in "Cancer 35" or whatever, and pin it down loosely. Tightly enough for interactions that are with things in completely different volumes, but without the fine resolution that fucks up continuity and requires rewrites. When we go and get (or make) the chart for that volume, we can get (or assign) the precise coordinates.

Part of this is that the precise coordinates can be expressed in a more tractable and precise system, the same way that latitude and longitude have nothing to do with the location of coastlines.
Just a quick note - I've split this discussion off from the Proofreading EG thread and set it up under General Setting Discussion.

We are getting a bit far afield from the purpose of this thread and sufficiently involved in this discussion that I think it warrants a thread of its own.

I'll leave the posts relating to this discussion on this thread for another day or so and then delete them to avoid confusion with the thread's main purpose.

Please continue this discussion on the new thread created for it.



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Just gonna note here that in the Pacifica article, "the Denebola Incident" is bolder incorrectly.
James Rogers, Professional Idiot
(12-25-2015, 10:04 AM)Centauri5921 Wrote: Just gonna note here that in the Pacifica article, "the Denebola Incident" is bolder incorrectly.

Hey. I was just gonna note here, er, I'm sure it's just a mistake, although I noticed that on the To'ul'h Prime article, it is mentioned that there are six planets in the system, although the image depicting the To'ul'hian system shows only five planets. The Neptunian world of K'at'sa'thos'kul seems to be missing. ;p
James Rogers, Professional Idiot

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