System Generation rather confusing/vague

[Kaelic]

I'm trying to follow the process to generate a system, but I find the explanation in the rulebook quite confusing, vague or obtuse.

I'm at the stage of generating the Stars and placing Worlds in orbits. When generating a "Spectral Type" you roll Flux, then you roll Spectral Decimal. What's a Spectral Decimal? What page is that clarified on? How am I meant to roll 0-9? Is that the star size? What does the Special Type apply to on Chart 2 on page 436? Is that the letter? If I get +4 I suppose the Spectral Type is M. Do I roll on this chart again and cross reference the new flux with M? So if +4 again I'd get M VI? Is that the size? Where does the decimal come in?

From this, how do I place planets? It says to place them in orbits, but which orbits do I select? I notice in an entirely different part of the book, orbits range from 0-19. Okay fair enough, but where do I place them? Is there a chart to select them?

On page 429 it says to place the MainWorld according to Chart G. Where is Chart G? I can't find a single chart related to orbits titled Chart G. Placing Worlds on the same page says to use the Placing Worlds Chart which presumably is the chart on page 437 titled Basic Placement. Is this the same chart it means? I cannot see how this chart can be used to select orbits at all.

It's probably a lot to ask, but it would be cool if there was a run through example of generating an entire system and which charts it references (on pages, since the titles of charts seem...to not relate to anything).

 

[whulorigan]

. . .
I'm at the stage of generating the Stars and placing Worlds in orbits. When generating a "Spectral Type" you roll Flux, then you roll Spectral Decimal. What's a Spectral Decimal? What page is that clarified on? How am I meant to roll 0-9? Is that the star size? What does the Special Type apply to on Chart 2 on page 436? Is that the letter? If I get +4 I suppose the Spectral Type is M. Do I roll on this chart again and cross reference the new flux with M? So if +4 again I'd get M VI? Is that the size? Where does the decimal come in? . . .

Concerning Dice Rolling for 0-9 or 1-10 even spread:

T5 Core Book, p.23
Only Six Sided Dice. Only D6 dice are used in Traveller. Sometimes, in order to remain true to the D6 concept, the system contorts D6 die rolls to achieve special results (for example, even distributions from 1 to 10 or 1 to 9). While purists may object, no one else will mind if you use an available D10 or D20.

T5 Core Book, p.31 Even Distribitions (and Sidebar Charts)

EVEN DISTRIBUTIONS
Even Distributions are contrivances to contort D6 results to correspond to non-D6 (specifically decimal dice or D10) results. Even Distributions use six-sided dice to produce a range of numbers beyond 1 to 6 (specifically 1 - 9, or 0 - 9 or 1 - 10).

Even Distribution 1 to 9. Roll two dice and consult the Even Distribution From 1 to 9 Table. This table is most commonly used in creating the Population Multiplier associated with the population exponent of worlds. Because the population multiplier modifies the exponent, a result of 0 or 10 is not applicable (zero creates a zero result; ten increases the value to the next order of magnitude).

Even Distribution 0 to 9. Roll two dice and consult the Even Distribution From 0 to 9 Table. Even distribution between 0 and 9 creates the equivalent of a decimal die (D10).

Even Distribution 1 to 10. Roll two dice, consult the Even Distribution From 0 to 9 Table, and add + 1 to the result.

Concerning Stellar Classification:
All stars in astronomy have their Spectral Classification subdivided into a decimal classification from 0-9. A 'perfect' example of a given spectral type is given a decimal value of "0" (i.e. a "G0" star). If a given star's spectral type falls somewhere between two spectral classifications, it is given a decimal value as to how far between the two "standard" classifications it lies. For eample, the Earth's sun is a "G2" star - meaning that it is a G-type star that is two-tenths of the way toward a K-Type star. (A G9 star is virtually a K-type star).

Spectral Types for common stars follow the prgression O, B, A, F, G, K, M where O is a large hot blue star and M is a dim cool red star.

Spectral Classification

O - Blue
B - Blue/Blue-White
A - Blue-White
F - White
G - Yellow-White (traditionally called "yellow")
K - Yellow/Yellow-Orange (traditionally called "orange")
M - Pink-Orange (traditionally called "red")

Star luminosity (i.e. "size") is (mostly) independent of this (at least for the purposes of the roll on the table, at any rate). Luminosity-size is graded as roman numeral appended after the spectral classification based on the following definition:

Luminosity/Size Classification

Ia - Bright Supergiant
Ib - Weak Supergiant
II - Bright Giant
III - Giant
IV - Subgiant
V - Main-sequnce ("normal-dwarf") star
VI - Subdwarf star
VII or D - White (Degenerate) Dwarf Star

T5 also uses the generic classification of "BD" for Brown Dwarfs of the L, Y, and T spectral-classifications.

So our sun is a G2 V star - a Yellow-White (G-type) main-sequence dwarf star.


My understanding of Table 2 on p.436 is that you roll Flux first for the Spectral type (located in column 1), and then roll flux again for Luminosity/Size (consulting the column corresponding to the previous spectral class roll that you just made).

 

[OjnoTheRed]

From this, how do I place planets? It says to place them in orbits, but which orbits do I select? I notice in an entirely different part of the book, orbits range from 0-19. Okay fair enough, but where do I place them? Is there a chart to select them? On page 429 it says to place the MainWorld according to Chart G. Where is Chart G? I can't find a single chart related to orbits titled Chart G. Placing Worlds on the same page says to use the Placing Worlds Chart which presumably is the chart on page 437 titled Basic Placement. Is this the same chart it means? I cannot see how this chart can be used to select orbits at all.

Page 437 - i.e. Chart "G WorldGen Other Worlds" is what you're looking for. Start with "W Worlds". Total Worlds in System are the MainWorld, plus Gas Giants and Belts, plus 2D Other Worlds. You have already generated the number of GG and Belts on page 432. Now you have the total number of planets / belts you need to place in orbits.

Now proceed to "P Placing Worlds" on that same page (p. 437). You first need to place the mainworld; earlier on page 432 you would have determined whether the mainworld is a satellite and any Habitable Zone Variance; see errata, however, as the results of +6 and -6 are not possible. You will need to know which orbit is the Habitable Zone for the star you have generated; for this, you will need the table on page 45 (yes, it is buried away from the System Generation sequence!) - e.g. our Sun is a G2 V star, and looking on the "V" column, you find that for spectrums G2 - G8 of V size, the Habitable Zone is Orbit 3 (unsurprisingly). If Mars was the mainworld in the Solar System, it would have "+1 HZ variance"; it would be in Orbit 4, and as a result, a cold world. There are some variations in those steps; if the mainworld is a satellite, place the GG in that mainworld orbit; if there are no GG's, place a BigWorld there (see below).

Now that you've placed the main world and possible one gas giant, you place the other gas giants. For each Gas Giant, determine its size and type by rolling 2D on the Gas Giants chart. Now that we know the Gas Giant is either small or large, now roll 2D on the "Basic Placement Chart" on p. 437 which expressed the placement of a SGG or LGG in terms of where it sits in the HZ. So rolling a 7 for placing a LGG results in "+2" - i.e. 2 orbits out from the HZ; in the Solar System this would mean Orbit 3 plus 2 = Orbit 5 (where the asteroid belt sits in real life). If another world is already in that orbit, simply adjust to the nearest available orbit.

Now there's a similar process for placing Belts, just use the Belts column.

Finally you then place each World - you rolled 2D to determine the number. After rolling on the World1 column, the world will either be in the Habitable Zone (which means the HZ-1, HZ or HZ+1), be an Inner World, or an Outer World. Then roll 1D on the right chart - The Inner Worlds, The Hospitables, The Outer Worlds. This gives you a "type" that you must then reference under "Other Worlds" to determine how you roll that world's UWP. For example, a RadWorld always has zero population, government, law and technology - i.e. is always barren. A BigWorld is rolled in the normal way, except Size is 2D+7.

Now that you've placed and generated the worlds in each orbit, it's time to move onto sattelites. Follow the instructions for Number of Satellites for each GG and World, and use the "Sattelites" charts under "Inner", "Hospitable" and "Outer" and generate them just like Worlds - except that if size of a satellite is equal to or more than mainworld, reduce it as instructed at the bottom of page 437.

It's probably a lot to ask, but it would be cool if there was a run through example of generating an entire system and which charts it references (on pages, since the titles of charts seem...to not relate to anything).

I think that's a good idea; the Regina system on page 430 doesn't have page references, but at least if you work through that example going through the sequence starting at Chart A World Generation Checklist on page 431, you'll probably be able to find you can follow the sequence.

Best of luck generating worlds!

 

[Timerover51]

Looks like a bit of a complicated system, aside from the fact that Spectral Types K and M are far more common than Spectral Types O, B, A, and F.

 

[OjnoTheRed]

Looks like a bit of a complicated system, aside from the fact that Spectral Types K and M are far more common than Spectral Types O, B, A, and F.

It is somewhat; yet it is a simplification in many ways over the Book 6 and MegaTraveller system generation processes.

 

[Frankymole]

To roll 0 to 9, why not simply use the old Traveller method of rolling a first die for an odds or evens (or 1-3 versus 4-6) result to tell you whether or not to add 5 to a second 1D roll? Natural sixes get rerolled. A result of 10 is zero. No tables required. Two differently coloured dice mean you can do it all in one roll of the dice.

 

[Timerover51]

It is somewhat; yet it is a simplification in many ways over the Book 6 and MegaTraveller system generation processes.

I never really liked the complexity of either of those. I prefer a modified Book 3 system, and worry about the primary or other planets if required. I guess I do need to have some idea of the primary however, so as to deal with jump shadow. The problem with that is how to deal with the case of the target system being on the wrong side of the departing system sun.

Adding in the system's primary jump shadow considerably complicates trade and travel.

 

[OjnoTheRed]

When I was younger, I would entertain myself rolling up a system using Book 6 or MegaTraveller of an evening. It wasn't really practical Refereeing, though: players really do mainly deal with the main world and that's it.

I now take a MOARN approach: what's the deal with the primary (especially: is the MW inside the 100D limit?), and perhaps where is the nearest GG for refueling, and maybe plan an adventure location.

I'd say dealing with the jump shadow of the primary interfering by being in the way would mostly be dealt with by navigating obliquely to the world, but obviously could add substantial travel time. It would intefere with passenger services in an interesting way, creating travel 'seasons' as the planet moved around the star.

 

[robject]

I never really liked the complexity of either of those. I prefer a modified Book 3 system, and worry about the primary or other planets if required. I guess I do need to have some idea of the primary however, so as to deal with jump shadow. The problem with that is how to deal with the case of the target system being on the wrong side of the departing system sun.

Adding in the system's primary jump shadow considerably complicates trade and travel.

I tend to ignore everything that's not important to what the players have to do. If there's a jump shadow but they're not being chased by something, then I don't bother. So far, they haven't ever been chased by anything, anyhow.

 

[Kaelic]

Best of luck generating worlds!

Thanks for this post, it has helped immensely. Since you seem to know, I've got a couple follow up questions.

1. Gas Giant type L on a roll of 1, from 2d6. I've not seen a modifier that comes into this roll, does this mean this Gas Giant type is never going to come up, or have I missed a modifier?

2. In the Regina world gen example, this happens:

Create world 5 of the system’s 12. On World1 Column, 2D = 5 =
Orbit 4 = a Satellite of the Gas Giant in Orbit 4. As a Satellite in Orbit 4, HZ Hospitables Satellite table = 1D = 4 = Hospitable.

This suggests to me that when placing a world in an orbit, or finding the closest, it includes going into satellite orbits if a Giant occupies said orbit?

So does that mean the procedure for selecting a World's orbit is:
1- Roll on Basic Placement Chart
2- If not Occupied, world goes here
3- If Occupied, if the world is Gas Giant (or BigWorld?) check if available Satellite orbits
4- If no available Satellite orbits in GG or BigWorld, select next nearest Orbit +- from rolled Orbit
5- Repeat from 2 until a spot is found

3. The table you pointed out on page 45 (Habitable Zones) goes up to 12, and then has some extra numbers on the left. How is this table meant to be used beyond 12?

3a. Additionally, what about orbits 17, 18 and 19?

3b. What are the distances for orbits 13 - 19 in AU? Is that another chart somewhere? K1 on Pg 442 shows some distances in Light units, but not all orbits are actually labeled for their distance (such as 16).

4. Are Remote Orbit planets even rolled? There is a table for Outer Worlds but since Outer Orbits and Remote Orbits are explicitly named, I wonder if this means HZ+ (Outer Worlds) table on Page 437 precludes worlds in orbits 13-19.

Cheers

 

[OjnoTheRed]

1. Gas Giant type L on a roll of 1, from 2d6. I've not seen a modifier that comes into this roll, does this mean this Gas Giant type is never going to come up, or have I missed a modifier?

It's not you; there is no modifier, so yes, you can't roll a 1. We should make sure this is logged as errata.

2. In the Regina world gen example, this happens:
Create world 5 of the system’s 12. On World1 Column, 2D = 5 =
Orbit 4 = a Satellite of the Gas Giant in Orbit 4. As a Satellite in Orbit 4, HZ Hospitables Satellite table = 1D = 4 = Hospitable.
This suggests to me that when placing a world in an orbit, or finding the closest, it includes going into satellite orbits if a Giant occupies said orbit?

Yes, the example implies that way of doing things. But on page 437 it also says "If an orbit is duplicated or precluded, adjust to an adjacent or the closest possible orbit." - i.e. move it to an available orbit near as possible if occupied already / not able to be used (e.g. because of a large star). This latter rule would suggest that in the example they should have moved the fifth world to a nearby orbit.

I'm not hung up on either way of doing it, TBH. But I think in the case of Regina the confusing thing might be that the mainworld of Regina is already known to be a satellite of a gas giant and the walk-through has confused this or used a previous proposed set of the rules. That's happened a bit throughout the rule book.

So does that mean the procedure for selecting a World's orbit is:
1- Roll on Basic Placement Chart
2- If not Occupied, world goes here
3- If Occupied or not available (e.g. large star precludes first few orbits), , if the world is Gas Giant (or BigWorld?) check if available Satellite orbits
4- If no available Satellite orbits in GG or BigWorld, select next nearest Orbit +- from rolled Orbit
5- Repeat from 2 until a spot is found

The Regina walk-through you quoted does suggest this, but the rules on page 437 imply simply:

1- Roll on Basic Placement Chart
2- If not Occupied, world goes here
3- If Occupied, next nearest Orbit +- from rolled Orbit
4- Repeat from 2 until a spot is found

3. The table you pointed out on page 45 (Habitable Zones) goes up to 12, and then has some extra numbers on the left. How is this table meant to be used beyond 12?

The purpose of that table is to tell you which orbit is the Habitable Zone for that star. As the largest possible stars are Ia super giants and the hottest of those are A0's on this table, Orbit 12 is the furthermost habitable zone on this table. The fact that this table excludes spectrum types O's and B's is errata.

Of course, orbits go up to orbit 19. This is a half light-year from the primary.

3a. Additionally, what about orbits 17, 18 and 19?

Orbit 17 could get a world placed in it if the last world you place - rolling on the World 2 column - you roll a 2 on 2D. It could also be the orbit for a Far Companion (see page 436). Orbits 18 and 19 are not obtainable by placing objects from this set of rules, as far as I can see.

3b. What are the distances for orbits 13 - 19 in AU? Is that another chart somewhere? K1 on Pg 442 shows some distances in Light units, but not all orbits are actually labeled for their distance (such as 16).

The first column of the Decimal Orbits chart on page 44 contains the data you are looking for.

4. Are Remote Orbit planets even rolled? There is a table for Outer Worlds but since Outer Orbits and Remote Orbits are explicitly named, I wonder if this means HZ+ (Outer Worlds) table on Page 437 precludes worlds in orbits 13-19.

Yes; the last World that you place uses the World2 column on page 437. This gives access to the Remote Orbits (except not 18 or 19 as previously described). So one world might be quite far out. Note that Outer Worlds simply means any world 2 orbits or more further away than the HZ. The Outer and Remote systems are simply neat categorisations of different possible orbits in the star system.

Hope this helps.

 

[Wol]

Just to add to this. Is there a way of randomly generating a non main world sattelite orbit?