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3-D directions


Good day, folks. Are there any canonical terms for the "up" and "down" galactic directions in Traveller? Or any other appropriate names folks have come up with would be appreciated... I'm messing around with a small campaign using a simple 3-D starmap, and a bit stuck on the terminology. Thanks in advance for any help.
Originally posted by thrash:
I went through this on JTAS not too long ago, for the same reasons. As far as canon is concerned, there is no third dimension in interstellar space -- it simply does not exist.

(I find this unrealistic and extremely frustrating: after all these years, why not come out with an official explanation and conversion from 3D to 2D? What happens to all the "excess" stars -- Sigma Draconis, for one -- that exist but aren't on the jump map? I have written to "Ask Avery," but with no response.)
Yeah. I can understand it for the OTU - a lot of the Imperium only "works" from the perspective of a 2-D map, and I was OK with that when I played in the OTU - but I wondered if there might be some quasi-canon terminology for alternate universes somewhere. Absent that...

Originally posted by thrash:
I recommend "boreal" and "austral," for the direction out of the page as you look at the standard map of the Imperium and into it, respectively.
I'll just steal yours, thanks! :D

Originally posted by thrash:
If you're making conversions from heliocentric coordinates (using, e.g., the formulae on Winchell Chung's excellent 3D starmap site), the adjustments should be fairly obvious.
Thanks for the info. At this point, I'm not using any real star locations nor the canon background - I'm just working up my own small setting at the tail end of a Long Night-type period - small ships, relatively small hands-offish Imperium, average TLs of maybe around 10-13, etc. Real star data is always useful for checking against my randomly generated stuff to make my setup at least somewhat plausible.

Originally posted by thrash:
I have done a lot of work on 3D mapping (including an article for JTAS online and revising the canonical list of known stars) and creating a viable 3D version of the Imperium. This gets wrapped up with some other hobby horses of mine (realistic population distributions and small ship universes, primarily), but I'd be happy to share what I have or discuss the subject further.
Thanks for the offer! Sounds like you're far more ambitious than I am, I'm just setting up a few 5x5x5 parsec blocks and seeing where my muse takes me.
I loved the 2300AD map for just this reason and have insisted upon using it for a basis for my Rim campaigns since it publication. It has some problems (names and some incorrect entries), but these are minor problems so far as game mechanics go. Its a mite restrictive, but 700+ systems are plenty for a campaign especially if you treat about half as frontier. If you add the map from the "Kafer Sourcebook" you can gain several new systems.

I'm currently transferring the data from these maps to a new hex map system consisting of hex shaped sectors 15 hexes across,each hex representing 1LY with the sector being 15LY deep.
It will take a while,but I think it will be well worth the effort. Perhaps I'll finish it this decade.

Since CT uses parsecs for its jump numbers, I extended the rules to say a ship could jump say two light years using 6% of its mass in fuel (3% per light year --a little cheat, but pretty close to the original :rolleyes: ). I used 10 hours per light year for time passage, not quite canon,but close enough for government work

3D movement is much more realistic and well worth the effort involved, in my humble opinion.

Just a thought,
Winchell's site also has some links (or at least he's got them somewhere) for some files (don't remember if they are spreadsheet or flat file) that have all the near stars to earth coalated from several catalogs and one that has all the likely candidates for life (dropping out the real dogs... not an astronomer, so don't ask me to say which those were....) - a smaller file. These make a good basis for games.

Wasn't there some claim, as an aside, that some of the stars in the 2300 AD starmap were 'inserted' for copyright reasons? (ie if you steal our map, instead of doing it yourself, we'll be able to tell since we have some bogus entries)? Or is that just Urban Myth?
I like in/Out North/South Spin/Trail as my three axis on the few occassions that I bother making a 3D cluster. Given that the cluster is far enough away from Gal Center, the curve of Spin/Trail is small enough to ignore (unless you are actually plotting the Jump) Ditto for actual star motion.

The Mink

I always take my Diary with me on Jumps, you need something fabulous to read.
A map is an image. We don't really see latitude lines painted on the surface of the Earth. Nor is there a continental sized monument to "xyx cartographers" in any corner of the Earth. It is easy enough to say that starmaps for lay people are rendered differently than for navigators, and there main purpose is to give an idea of the rough relationship between the worlds-planetary maps are flat after all.
That said there should be a directional term for "up" and "down"
Jatay, planetary maps at TL-8 may be flat. TL-12 ones may be 3D holograms with realistic photoreal texturing based off of orthophotos (or their 3D equivalents) and DEMS data.

I suspect the portable, rollable-film holo-map will be very popular if it is ever perfected.
Directional term for "up" and "down" is altitude (at least planetside).

In the US, every State has a State Plane Coordinate System. In most cases it is a cylindrical projection optimized for minimal distortion. Most of the larger states have two SPCSs and I wouldn't be surprised if Texas and Alaska have more than two.

In the age of sail the use of "rutters" was common. Instead of having a complete set of maps (information jealously guarded by each country), a captain might be given only a limited set of landmarks, headings, and other data for a particular mission.

In a very limited scope you can pretend things are 2D, maybe the nearest half-dozen stars. Beyond that the 3D distribution becomes impossible to model in 2D.
Yep, I've tried and tried and tried. Once you get beyond about 50 Light years there are so many stars involved (about 750 I think) its very nearly impossible to map or even research. Besides, your players very rarely appreciate all the work you put in on the map, they's really rather you put the time in on your story crafting for the game "history" and the scenarios for their play, believe me.