Using Stellar Data

[DonM]

I was perusing the newest data package before sending it over to travellermap, and I realized something...

The method I use for actually using listed stellar data as a referee may not be the same as everyone else's methods, because I don't think it's actually discussed anywhere, for any edition.

Here's what I mean... Using the data for some systems in Regina subsector of the Marches...

Spin 1903 Pixie A100103-D 901 K1 V M0 V
Spin 1904 Boughene A8B3531-D 601 M1 V
Spin 1909 Hefry C200423-7 320 K6 II M2 V
Spin 1910 Regina A788899-C 703 F7 V D M3 V

Now, we collectors know that Speck is the brown dwarf that orbits Regina's primary, an F7 V, and there's that M3 V far star. [Yes, prior canon says Speck's a white dwarf, but if it was, it would have blown off the atmospheres of everything worth living on around Lusor when it became a white dwarf, so that can't be right. So for purposes of this discussion it's a brown dwarf, even if the data says "D" which says otherwise.]

But if you're just looking at that data, what are everyone's conventions as to how to interpret this.

For example, with Pixie and Hefry, which star does the homeworld orbit (and since they are both crappy, it could be either). Or, is either of Pixie or Hefry's companion stars a close companion, etc. Or if you didn't know what canon says about Regina, you might think the mainworld itself orbits that M3 V instead of the F7 V.

Now, I have my personal conventions for how I treat this, because I've never seen any edition of Traveller give rules on handling it. But I'd like to know what other folks do, because I don't think I've ever seen any discussion on this.

I am aware that the T1248 Bearers of the Flame actually addresses this, but without explaining the system (which is unfortunate, because it's an excellent system).

But I want to see if either a) there are rules somewhere that I have completely missed, or b) other ways of handling this that make much more sense than mine (which is actually completely expected).

 

[thalassogen]

I tend to list stars in descending order of mass (while astronomers usually list them in descending order of brightness), therefore I don't expect the listing to say anything about the mainworld's actual star.

When placing the mainworld I usually compare the UWP to the available stars and when local life seems possible I go with the most stable main sequence star available.
Otherwise if the world has an atmosphere I still tend to stick to V or VI stars. White dwarfs or giants only get used for barren rock worlds or asteroid belt mainworlds.

 

[OjnoTheRed]

I interpreted the data as saying the first star was always the primary, and then place the other stars at random in a given rule set, picking up system generation where the data leaves off. To give living worlds (e.g. Ag, Ri) a fighting chance at a reasonable result, I'd kick companion stars off HZ's. Having said that, I've not double checked stellar masses to see which star is orbiting another star.

At the risk of going off-topic, what frustrates me is fairly cold stars with worlds that you'd expect to be quite Earth-like from their UWP's. When doing MegaTraveller World Builders' Handbook, you often end up with an Ag or Ri world turning out to be a cold Twilight Zone world with an average temperature close to crop-killing. To compound matters, the UWP related TL Mods did not bless the world with a higher TL.

This is made interesting with the T5 Native Life Status for a given world - if the population is 7+, you are likely to need to generate a Sophont for the world. This can square lower technology levels with these situations, but a lot of canon assumes an even more human dominated society than the emergent universe in T5.

 

[whulorigan]

One way to do it is to always list the mainworld-star first in the stellar listing (which explains some of the "M2V M0V" entries, which should be listed the other way around). But that still leads to ambiguities.

Using the Regina example:[FONT=arial,helvetica]
[/FONT]

[FONT=arial,helvetica]F7V BD M3V[/FONT]
​

If I knew nothing about the Regina system, Regina could orbit:

1) The F7V
2) The BD
3) The F7V
4) An F7V-BD close binary pair
5) A M3V-BD Far Companion
6) The entire trinary system at a far distance
7) (etc for a few other possibilities)
​

Obviously some could be ruled out logically based on Regina's UWP. But it would be nicer to have clarity.

I always liked the TNE:1248 System (as best as I can interpret it since there is no explanation anywhere that I know of).

My "guess" at the system is that the 'asterisk' represents the star or star system that the mainworld orbits, and that brackets make clear what are "close companions" relative to one another.

So for example:

1) A0V G8V* M5V - Mainworld orbits G8V star
2) [A0V G8V]* M5V - Mainworld orbits barycenter of A0V-G8V system
3) [A0V G8V] M5V* - Mainworld orbits M5V companion - A0V-G8V system is the close companion system that the M5V orbits as a far companion
4) A0V [G8V M5V]*- Mainworld orbits barycenter of G8V-M5V far-binary companion-system

etc.
​

I am not aware of any other system thru the various rulesets that actually attempted to address this, other than MJD's system.

Perhaps you could PM or e-mail MJD and ask him definitively how the system works?

 

[DonM]

I actually have the full explanation of the T1248 system (which actually only appears on Bearers of the Flame) from Mike West. So I do know how that works...

 

[whulorigan]

I actually have the full explanation of the T1248 system (which actually only appears on Bearers of the Flame) from Mike West. So I do know how that works...

I do not suppose that is publicly available or downloadable in a document or PDF somewhere, is it?

 

[DonM]

I do not suppose that is publicly available or downloadable in a document or PDF somewhere, is it?

I'm hoping to get permission to include it in errata...

 

[Carlobrand]

A belated thought:

The Book 6 star generation system is biased toward sunlike stars for large population (8+) worlds and earthlike (atmosphere 4 - 9) worlds: if you're starting from a pre-generated world, you get a +4 when rolling those. Companion stars are rolled randomly, but the DM based on primary star type means most companions will be small red things. Based on that, the primary star is more likely to be F/G/K sunlike where there are large-pop/earthlike worlds, the companions in general are more likely to be red to orange main sequencers, and the companions of large pop and earthlike worlds will be exclusively red to oranges.

My observation of the binary systems in the various sectors suggests they mostly conform to that: very few yellow or brighter stars in the second or later position, heavily dominated by reds with a few oranges. I therefore infer that the second and later listed stars are companions as generated under the Scouts rules. However, there are a couple of exceptions: Melk in Alpha Crucis is an atmosphere-4 world circling a red main sequence with a yellow-white companion, and Garnadon in the same sector is a pop-8 world circling a red main sequence with a yellow-white companion. I presume that some of these systems, or even sectors, were generated before or without aid of Book-6.

At any rate, from the pattern, I'm thinking the first star is the primary, or we'd end up with more earthlike worlds orbiting dull red coals. The Melk/Garnadon situation is rarer than its reverse.

(Actually, the table puzzles me because there doesn't seem to be a way to achieve the low rolls.)

 

[Supplement Four]

But I want to see if either a) there are rules somewhere that I have completely missed, or b) other ways of handling this that make much more sense than mine (which is actually completely expected).

Isn't this addressed in one of the three MT books that came with the core boxed game? I seem to remember some extended data info address with the Spinward Marches sector data presented with MT.

 

[DonM]

Isn't this addressed in one of the three MT books that came with the core boxed game? I seem to remember some extended data info address with the Spinward Marches sector data presented with MT.

Certainly NOT the Spinward Marches Data chapter of Imperial Encyclopedia. Or the Domain of Deneb info in MTJ #3.

 

[Carlobrand]

The first time I ran into it was in the Spinward Marches Campaign, where the stars were simply labeled Star1, Star2, and Star3. Of course, I tended to assume the primary was Star1; I couldn't fathom a reason that they'd take the primary and then call it Star2.

 

[DonM]

That really, really doesn't do what I'm talking about.

For example, using the system from Bearers of the Flame, T5's Regina comes up as:

(F7 V* BD) [M3 V]

So the question is, does such stellar data actually make sense, and would it be easily usable (if it was in a data file, could it be easily read and parsed, etc?

 

[Carlobrand]

That really, really doesn't do what I'm talking about.

For example, using the system from Bearers of the Flame, T5's Regina comes up as:

(F7 V* BD) [M3 V]

So the question is, does such stellar data actually make sense, and would it be easily usable (if it was in a data file, could it be easily read and parsed, etc?

I like that. Only comment I have is the Roman numerals made it difficult to design an excel formula that could read them well. That's the standard nomenclature, but their positions change according to how many characters are there, with the result that the companion star data was misread if the primary was anything but a V or I. Writing a formula that takes the varying number of characters into account is doable but made it too large for the cell; I'm finding it easier to go back and add spaces to put the star data in readable position for the spreadsheet, rather than making a translator cell to deliver the information to the main cell. Suggest you add a couple of extra spaces for the data file - V__, IV_, etc. - to make it easier to read, if that's not difficult. Other than that, Excel doesn't care so long as you tell it where to look. I can't speak for other systems.

Why was T5's Regina changed from the CT Regina? Darida only had a couple worlds, neither likely to be affected by the difference between an M3 and an M6.

 

[DonM]

I like that. Only comment I have is the Roman numerals made it difficult to design an excel formula that could read them well. That's the standard nomenclature, but their positions change according to how many characters are there, with the result that the companion star data was misread if the primary was anything but a V or I. Writing a formula that takes the varying number of characters into account is doable but made it too large for the cell; I'm finding it easier to go back and add spaces to put the star data in readable position for the spreadsheet, rather than making a translator cell to deliver the information to the main cell. Suggest you add a couple of extra spaces for the data file - V__, IV_, etc. - to make it easier to read, if that's not difficult. Other than that, Excel doesn't care so long as you tell it where to look. I can't speak for other systems.

Why was T5's Regina changed from the CT Regina? Darida only had a couple worlds, neither likely to be affected by the difference between an M3 and an M6.

Darida's small gas giant Elazair has a satellite Gagamshir with a ATM of 3 and a HYD of 4. M5-M9 have no habitable zones and while an M0 only has a habitable zone in orbit zero, the M3 is a better fit than the M6.

And if Speck is really a white dwarf, it would have blown Regina's atmosphere off (as well as the other five worlds in the Lusor system which have atmospheres). So Speck became a brown dwarf in T5.

As for data files, we use Excel for everything now. It makes for faster manipulation. I'm considering moving to Access as we get more sectors into the T5SS, because I'm to the point where queries would be real useful...

 

[DonM]

And I'm looking for some folks to give comments on the Marches parsed to match the Bearers of the Flame stellar format.

Drop me a note at don.mckinney@gmail.com if interested...

 

[Carlobrand]

Bearers of the Flame is a T5 supplement? What does T1248 mean?

 

[whulorigan]

Traveller: The New Era 1248 (TNE:1248)

Bearers of the Flame is a T5 supplement? What does T1248 mean?

Bearers of the Flame is the 2nd Book in MJD's Traveller: The New Era year 1248 series.

The Sourcebooks for the 1248 era are:

1) Out of the Darkness (Main setting Sourcebook)
2) Bearers of the Flame (Details the 4th Imperium in Gushemege)
3) The Spinward States (Details the evolution and breakup of the Regency/Domain of Deneb)
4) The Freedom League (details the Solomani Rim / Diaspora border)

They are available on the Traveller: The New Era 2 CD-ROM.

 

[DonM]

Bearers of the Flame is a T5 supplement? What does T1248 mean?

whulorigan explained this, but the stellar parsing we're looking at using for the T5SS (and discussing in this thread) comes from Bearers of the Flame.

 

[BillDowns]

That really, really doesn't do what I'm talking about.

For example, using the system from Bearers of the Flame, T5's Regina comes up as:

(F7 V* BD) [M3 V]

So the question is, does such stellar data actually make sense, and would it be easily usable (if it was in a data file, could it be easily read and parsed, etc?

So what does this nomenclature actually mean?

 

[whulorigan]

For example, using the system from Bearers of the Flame, T5's Regina comes up as:

(F7 V* BD) [M3 V]

So what does this nomenclature actually mean?

In TNE:1248, for the above example, the parentheses imply that the noted component is a "close-companion" configuration (the BD orbiting within Orbit #0 of the F7 V). The brackets imply a Far Companion to the F7 V Primary. The asterisk denotes which star or binary-component the Mainworld orbits (in this case, the F7 V).

If the BD were NOT a close companion (say a near binary-component in Orbit #3, for example), then the F7 V and BD would not be enclosed in parentheses.