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Big Imperium - Or Traveller 3D


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What home rules would be necessary for Traveller 3D?
We discussed in another thread that our arm of the milk way at this point is 900-4000 light years think yet we're playing in a 2D Imperium map.

We might assume that the imperium in such a universe only takes up the denser populated piece of the map. Everything else is frontier above and below. + and - modifiers to a planet could be used to indicate the Z access. We could also consider modifying the Jump system through a simple modification.


You could assume the sectors actually represent a series of interconnected 3D clusters, sparse enough to allow a 2D representation. You'd still need to 'fill in' the spaces between them with systems, most of which are more than some number of parsecs away -- 5 or 6 parsecs would present a prohibitive gap for most ships.
Sorry to be a wet blanket, but some guys at JTAS tried this before...
The 3d will only work on a computer - there's no way you can still run a Trav setting with a pencil, paper, D6, and the rules when you are adding a 3d element. Just jumping up or down and out or in requires trig, not something I wish to engage in during play.
Would it work on a computer? Yes, it would be ALOT of work, and it would be totally cool, I'm just saying not many folk are going to put in the time and effort for what will essentially be a Variant of Traveller...
I do wish ya well, and would probably plunk down $49.95 for the finished product...
Originally posted by Savage:
What home rules would be necessary for Traveller 3D?
A way to actually implement maps of reasonable size, in a way that's human readable, on paper. It's not at all easy to do for any significant scale.

It doesn't help that if you make the third Imperium reasonably thick, you increase the number of stars by a factor of around 10.
For my money Traveller 3D has been done...it's called 2300 AD. I really am not being flippant here, but have reconciled that Traveller is 2D, and the amount of work it takes to make something 3D means that I will play in the 2300 AD universe. GURPS Space has info for 3D Mapping, but even they say make sure you only detail a small amount of space, too much and you will need a computer just to keep track of the stars.
Frankly one of the biggest handwaves in Traveller is the flat map, and I like it.
If you want to create YOTU, then there are some excellent 3D mapping programs out there, or you could use a public database online that has a listing of nearby stars. Then just pick a system and develop it. Sorry I don't have the links handy, it is late at night and I am tired. Good luck with your project
IMTU I dropped all questions about 3D. Of course the Universe is 3D, only those astrogational jump reference maps are done in 2D. It took Imperial astrographers years of research to produce a simple map which can show you the relative jump distances between the Star systems. (Well, it works just like some subway map, if you ever travelled by subway you know what I mean. You know how to get there, but the REAL position is another matter)
3D Traveller settings are fine so long as you keep it small. You might want to adjust the jump drives so that they jump number represents light years instead of parsecs. A jump-1 should take you 5 light years. A jump-2 should take you 8 light years. A jump-3 should take you 10 light years. A jump-4 should take you 12.6 light years. A jump-5 should take you 14.6 light years, and a jump-6 should take you 16.5 light years. This should approximate the same number of stars you would ordinarily be able to reach with these same jump drives in a 2D Traveller universe. The formula I used was:

Jump-number^(3/2) * 5 light years.

A 3D imperium would be smaller and more compact if it had the same number of stars. The best setting I find for a 3D universe would be Traveller-The New Era because the players would know about only a small section of space. The fallen Imperium is presumed to cover a much larger area, but all the map data that the PCs were able to get ahold of was destroyed by the virus. The PCs don't know where they are in relation to the rest of the imperium. Just roll up randomly in a 20-ly by 20-ly by 20-ly cube. Such a space typically contains about 70 stars. Roll 2d6x10+1d10 to determine the number of star systems. Roll (1d20-1, 1d20-1, 1d20-1) to determine the coordinates in light years of each star system and roll their types and planets normaly.
Yeah, it sounds good when I say my car can go 1,140,480,000 ft/sec, but it seems so unweildy.

<Why would you want to lower the unit of measurement used? A parsec is BIGGER than a LY>

Well some varying responses.
I've seen most other 3d options. (I'll have to checkout Gurps). Most say its tough. I'm a fan of 2300AD and helped play test in for Smith. But its not the Imperium and jumpspace travel.

I'm also a fan of vectors (it comes with having sailing as a hobby) and this might be a perfectly applicable method of expansion. Perhaps, for giggles, we should look at it another way.
Present estimates are 1 in 50 systems might have a mars or earth.

Lets take the smaller number 900 light years (225 parsecs MOL) But much is frontier perhaps only 60% is not sparce or frontier. Now its 540 lyrs (135 parsecs MOL) or less than 2 subsectors thick.

But it does mean 134 additional layered maps, if I used the present philosophy. Hence, If each world in the existing map were assigned a + or - one parsec, the map would cover 3 layers (12 lyrs thick MOL). If this were done with every map I'd require 45 maps of the imperium universe.

Yep, it would probably require a program to create .

I'm also a fan of vectors (it comes with having sailing as a hobby) and this might be a perfectly applicable method of expansion. Perhaps, for giggles, we should look at it another way.
Present estimates are 1 in 50 systems might have a mars or earth.
I agree that Earthlike planets are probably quite rare. A Mars on the other hand is likely quite common. I define a Mars like planet as one with an accessible surface (unlike Venus) with an atmosphere, water and all the elements available to support a human colony locally. You can't walk around on a Marslike planet without a vacc suit. Mars like worlds don't meet the conditions for supporting complex life, they are a fair bit colder than Earthlike world, and possess a very thin atmosphere. Actually a very thin atmosphere makes it easier to insulate the vaccsuit against the cold. A Titan-like world would be more difficult to survive in a vacc suit since the thick cold atmosphere would quickly draw heat away from a vacc suit unless it was heavily insulated. I think any planet size 3 to 6 in a Mars like orbit would become a Mars like world. If a gas giant were in this orbit you could have multiple Mars like worlds in the form of satellites. Ganymede is about the size of Mars. Earthlike worlds are the true rarity.
I want more exploration in the 2D universe. What lies beyond the great rift? What lies behind the 2K Worlds or the Hiver Federation? What lies rimward of the Sollies and Aslan? What lies coreward of the Vargr?
We have like .3% of the galaxy mapped in our piddly 2D map. Lets do a long range exploration ala Consulate Core or the Sollies Rim Expedition. I want to know if the lousy K'kree are using the stalemate in charted space to expand and exterminate trailing or coreward. I would like to meet those interesting civilizations before they are snuffed out. What if there are a couple more major races out there? Maybe they have high tech - maybe they can jump more than 6 parsecs...We'll never know unless we look.

I get the impresion this is somewhat of a mistreated horse but I have to ask the questions.

Does this issue affect game play that often??

I'm a Traveller virgin.
Originally posted by BluWolf:
I get the impresion this is somewhat of a mistreated horse but I have to ask the questions.

Does this issue affect game play that often??
if every system in the spinward marches had one adventure written for it, that would be 437 adventures. that's more than most referees can produce.
Originally posted by BluWolf:
I get the impresion this is somewhat of a mistreated horse but I have to ask the questions.

Does this issue affect game play that often??

I'm a Traveller virgin.
It doesn't have to affect game play. Without alteration of the background 2D cosmology, a GM and Players, playing once a week and getting to one or even two worlds per session, could never visit all the worlds in Charted Space. They'd all die of old age first. If not, their PCs would probably die of old age even if they were on anagathics. Even the characters in the DGP Traveller's Digest adventure series, travelling from the Spinward Marches to Capital/Core, to Terra/Solomani Rim, over through Aslan space and up across the J-5 Route and through the Trojan Reaches to return to the Spinward Marches took, what, how many years of game time?

To be fair, the 2D cosmosology rubs some people the wrong way on the verisimilitude and science-accuracy side of things. In 3D space, to some, a flat map just doesn't make sense. Once, when I was much younger, it did the same to me. Now I don't think twice about it.
Most of Charted Space is not mapped out in any detail, you could have a 3D map in those areas. I like the premise of a post apocolyptic Traveller setting where map data is unavailable or has been corrupted with the locals only knowing the local area. It Charted space was 3D, the Imperium would have 1,154,000 worlds in it instead of 11,000. I doubt it anyone has the UPP for all 11,000 worlds so they are both just big numbers. It doesn't make much difference to the players if you use either of those two numbers.
BluWolf. Does it affect game play? Good question...yes and no. Part of the fun of traveller is emulating space adventure travel. I'd find it interesting to have a 3d universe and more realistic (if that matters).

There are alot of arguements about traveller. And what is fun. Some like running about with less money than firefly from one fire fight tothe next. Others enjoy the tactics of space battles; hunting pirates. There is no reason that vector based travel is not a possibility. 1 million worlds will be more difficult to visit but only 20,000 have earth like worlds. More than any small group can visit. But most refs should pick out a section of the universe and ref in that section planet jumping can get dreary.

It does allow more variation in play. The universe is not flat. A small universe is just as playable as a large one. If we're going to have an imperium shouldn't it be realistic not flat.

Traveller is about the ships it has always been about the ships.

Savage (aka Columbus)
or just add vertical layers where alternate layers are offset by half a hex on the assumption that vertical layers are not a full parsec up (that way the maths works out)

print your maps on transparencies with the hexes as thin (dotted ?) lines with the level identified

to keep the feel of the jump 1 mains without drastically increasing the number of stars you need to move systems between layers. to stop the universe being totally barren looking there are many star types that shouldnt be able to have planets and thus are normally ignored but might just explain how empty hex jumps/meetings can happen

dashes represent systems .... dots represent blanks were the system is on another layer (in case this doesnt line up)
2Dmain : - - - - - -
3D main :
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I've played "3D Traveller"... it works if you can make a map that your players can follow. so-called "Subway" maps help... but it gets rather hard for people to visualize 3d space without a computer model to work with.