T5 System Mapping Questions

[Shikage]

I have a few, hopefully quick, questions about generating star system maps and the various objects within them. Mostly in the rules and limits surrounding satellites of the worlds within the system.

To start with, if you are fully mapping the system, do you roll up descriptions for each satellite of each world using the Hospitable and Outer Satellites tables? Then would you generate full UWPs for those based off the satellite type? Are there limits to the size of satellites, such as no larger than the planet they orbiting? Do you determine orbits of these relative to the planet?

Or would these more commonly be left undescribed and noted simply as moons of the given planet?

 

[aramis]

I have a few, hopefully quick, questions about generating star system maps and the various objects within them. Mostly in the rules and limits surrounding satellites of the worlds within the system.

To start with, if you are fully mapping the system, do you roll up descriptions for each satellite of each world using the Hospitable and Outer Satellites tables? Then would you generate full UWPs for those based off the satellite type?

Yes, and yes, if needed. Note that Satellite size is convoluted; go to page 413, roll on the correct table on the bottom left, which is a 1d table, but is apparently missing modifiers.

Are there limits to the size of satellites, such as no larger than the planet they orbiting?

Yes. Well, maybe. If you want, you can simply take the rolls as is, and the smaller orbits the larger.

Do you determine orbits of these relative to the planet?

Yes. IIRC, in planetary diameters (of whichever is larger).

Or would these more commonly be left undescribed and noted simply as moons of the given planet?

You can do that if you want. The "Write Up Everything all at once" is a break from Marc's MOARN guideline. So, once you've got the fit of GG's, Belts, and mainworld, you're good to go, until you need the additional.

Don't bother with the moons unless either (1) the players go toward that planet, or (2) you need to place a moon base or population somewhere.

 

[OjnoTheRed]

Just to add to what aramis said, the 5.00 rules (IIRC) said that when rolling for Satellite size, if it was equal to or greater than the size of the planet, reduce it to the size of the planet minus 3. That takes care of most cases reasonably well.

The "edge case" is that the minimum size is 1. That would seem to imply that a planet of Size 1 could have more than 1 satellite that were also of Size 1, multiple bodies of similar mass would be doing a complex (probably impossible) dance around a common centre of gravity in a single orbit around a star. I'd say just ditch results that sound like they can't happen if you need to map them.

 

[aramis]

Just to add to what aramis said, the 5.00 rules (IIRC) said that when rolling for Satellite size, if it was equal to or greater than the size of the planet, reduce it to the size of the planet minus 3. That takes care of most cases reasonably well.

The "edge case" is that the minimum size is 1. That would seem to imply that a planet of Size 1 could have more than 1 satellite that were also of Size 1, multiple bodies of similar mass would be doing a complex (probably impossible) dance around a common centre of gravity in a single orbit around a star. I'd say just ditch results that sound like they can't happen if you need to map them.

The minimum size in prior editions was "S" - which was "under 800 km."
(S was chosen because it is memorable for "Small", and 0 was taken for asteroid/planetoid belt. A roll of 0 or below for a non-belt was converted to S.

Note that one of the secondary types can generate 0 or lower totals. Worldlet is 1d-3. Which can be -2 to +3.

Thing is, Marc added new sizes, and S is now a size of LGG. So, barring rules otherwise, it's GM's call on how to handle it. I'd use a symbol, myself, in place of the letter, so as to avoid overlap. Since @#$&*"', all have strong uses, not good choices; anything outside the standard 256 is a problem, too. (most text is now windows 1252, not actual ASCII, and many others are UTF-8. True ASCII is 7-bit...) So, it needs to be visible, not too easily confused, and in the first 256... which leads me to ~ ... I'd actually prefer the UTF8 easy option of "¢" - first, it's distinct in being a composite, second, it's single en-width. It's also easily handwritten.

Other candidates: • ø Ø - bullet's bad because it can be mistaken for 0 when handwritten. The O-slash ø Ø is pretty good, tho'. It's in most 256-character code pages in use.

I think I'll suggest that to Marc...

 

[OjnoTheRed]

Now that I look at it, I must have assumed that the minimum size was 1 under the T5 rules rather than read it somewhere.

I do seem to remember reading somewhere that the system generation rules in T5 were trying to avoid mapping or generating every last object. But that could have been a general comment about the MOARN philosophy.

If we are going to track some objects smaller than size 1, I like your idea of alternative symbols. It means we have a way of encoding objects like Phobos and Deimos or Ceres in our system generation if they're not part of planetoid or asteroid belts.

 

[aramis]

Now that I look at it, I must have assumed that the minimum size was 1 under the T5 rules rather than read it somewhere.

I do seem to remember reading somewhere that the system generation rules in T5 were trying to avoid mapping or generating every last object. But that could have been a general comment about the MOARN philosophy.

If we are going to track some objects smaller than size 1, I like your idea of alternative symbols. It means we have a way of encoding objects like Phobos and Deimos or Ceres in our system generation if they're not part of planetoid or asteroid belts.

The self-rounding threshold is 300 km diameter according to several papers. the ±50% guideline means the low end of 1 is 800 km diameter. This leaves a large gap: 300 to 800 km. (1d+2)*100 km... and those 300km objects are few enough to be notable. A couple asteroids, several KBOs, half a dozen moons.

 

[Shikage]

Thanks for all the responses. This has been really informative. I'll try looking over the rules again, not sure how I missed if there was information about the maximum/minimum relative size of a satellite.

 

[Shikage]

I do have one follow up question about the planet generation tables. In the Atmosphere table (pg 409 in my copy) it has what looks like some kind of code in the atmosphere descriptions such as S3, P1, C1, etc... It isn't clear to me the purpose of theses as well as how the Varies is handled for Atmospheres D, E, and F

 

[tjoneslo]

Those are the damage types and levels caused by the atmosphere types. S3 is Suffocating 3D, meaning you take 3D damage each combat round unless you have protection against suffocating. P is poison, C is crushing.

 

[Shikage]

Thanks tjoneslo, that definitely makes that bit a lot more clear!