World Builder's Handbook

[metlk]

So I purchased the WBH last week and am regretting it, but with some seriously mixed feelings. I understand the need to please the science purists, but I feel like I need an astrophysics and mathematics degree to be able to generate a convincing solar system. I liked the Deep Space Exploration book, but was wanting something that would provide some guidance on orbits and planet placement, as the book was vague and a little confusing on that part, and didn't offer anything beyond that. There is some stuff here I want to use, such as distancing between planets, jump shadows, a lot of the atmosphere stuff is good, and several other things and If you are the type that really want to get into the weeds to the point of atmospheric density based on altitude and how big the moons looks from half way up a mountain, you could probably have a lot of nerdy fun with this, but I just want to play a sci-fi game in a semi-believable future. I'm not looking for scientific accuracy. Close enough is good enough for me. Rule of Cool and all. I expected world building ala fleshing out and terrain mapping, not world building ala big bang. Lol. I have a crim/psych degree, math is not my area of expertise. Just give me tables with easy rules to follow (easy rules, not these nested rules within rules that affects many of the tables here. It's a confusing mess!)

Has anyone has came up with some quick hacks to implement a lot of the new details in the book without having to go through 100+ pages of math formulas to do it? I'm completely lost on how to simplify this for a for a dummy like me.

 

[MonsterX]

I'm not bothered by it, although I know that I'll very rarely or never actually calculate most of these things in the book. A lot of the formulas have autocalculators you can find on-line. Other things you can just kind of guesstimate if you know the variables involved and have some notion of their relative importance. Some formulas might turn out to be very important in a particular situation and then you can dig out the scientific calculator. Like you don't really need to know the distance to the horizon, unless the players decide to try to a sneak attack and need to fly as close as they can but stay out of line-of-site - suddenly you need a distance. For example. Or the exact composition of the atmosphere might not be important until the players what to do some kind of chemistry - then you need to know.

Even without going through the world building process more than a couple of times, the book gives a sense of how it all fits together.

 

[Vormaerin]

I always put interesting adventures ahead of scientific realism at the level of this book. But I use this book to reverse engineer things to a roughly plausible arrangement. Where would this world I just designed be in a solar system like this one? Or something like "Okay, I want this kind of climate effect. What's gonna need to be in albedo, axial tilt, etc? That'll usually give me some other ideas about the vagaries of the world.

But calculating the worlds from scratch using the formulas? Nah, that's not what I need.

 

[Geir]

The idea is that it is fairly modular. Some things, like a habitability rating, will require a bit of prerequisite work, and is really most relevant for an exploration or colonization campaign, but most things can be taken in isolation. For example, if all you wanted to do was look at details of the law level or government, you could do that... though whether just doing that for a small number of worlds is worth the purchase price, that's another story.

Like @Vormaerin says, its also useful as a tool to reverse engineer a justification for the type of world you want. Or at least reverse engineer a justification for it.

Obviously the more you use, the better the value, but I didn't intend it to need to be used in its entirety for every - or really any - system. I did it because I had to test the rules and because that's the sort of thing I find fun to do.

 

[metlk]

I finally spent about 4 hours muddling through it today and managed to get a group of planets and orbits created. The orbit# section was a bit confusing, but overall it looks like most of the scientific formulas (in those sections so far) are entirely optional for granularity. It'll go a lot faster in the future. Now to dig into the actual planet specifics.

 

[tytalan]

In many ways it’s the second half of the book that’s important for most Traveller campaigns. That’s were you get into things like law level tech level and social aspects of a planets population

 

[metlk]

I'm stumbling through all of this but man I keep coming up with more questions. I thought I understood the habitable zone. I have 13 bodies orbiting a single M0 star. I determined 8 was the baseline orbit with orbit# 0.76. From there, the separation was 0.9. To keep it simple, I didn't do any variances. From what I thought I understood, the orbit# on either side were the brackets for the habitable zone. I should have realized I had something wrong because that would imply there would only be three habitable planets at most per system, unless I really misunderstood orbit#s and planet placement. Now I'm trying to figure out the temperature of my first planet which is a size C at orbit# 0.11 but I can't find that anywhere and now I'm questioning whether it is still inside the habitable zone. I'm so lost.

 

[Vormaerin]

Determining the habitable zone of a star is covered on page 41 with this formula:

However, there is a nice chart on page 42 "Habitable Zone Center Orbits" that does the math for you. Looks like you did it pretty well, since you got 0.76 and the chart shows 0.72. I was not sure where you got separation of 0.9, but I think you just made a minor mistake. My calculations show 0.09.

The system spread on pg 48 says . Your baseline orbit # is 0.76. The Minimum orbit for your star is 0.02. You determined the baseline number to be 8. So the spread should be 0.74/8 = 0.09.

Your minimum orbit is 0.02. Your 8th orbit is 0.76. That's going to be a pretty tight system, as you might expect from a red dwarf. Without doing any variations or eccentricity, you have orbits at approximately:

1: 0.11
2: 0.2
3: 0.29
4: 0.38
5: 0.47
6: 0.54
7: 0.63
8. 0.75
9: 0.84
10+

The habitable zone variation chart says that 20% variation is within the habitable zone. So it is possible that 7 and 9 are habitable (as you expected). But they might not be. Venus and Mars are on the edges of Sol's habitable zone, but they aren't actually fun to live on.

 

[CordwainerFish]

But they might not be. Venus and Mars are on the edges of Sol's habitable zone, but they aren't actually fun to live on.

Mars in particular ain't the kind of place to raise your kids.

 

[Geir]

Mars in particular ain't the kind of place to raise your kids.

In fact, it's cold as hell

 

[metlk]

Those are close to the numbers I got, so it's good to know I did that part right. I was really thinking I missed something. I got 0.56 for #6. I did miss the 20% and just saw the +/-1 orbit# for the habitable zone. So at 0.56, that would be below 20% so it should be in the HZ? Same with #10? I should have 5 in the HZ, not 3? Also, I think i keep conflating "habitable zone" with "inhabited" which in universe they can be on a frozen asteroid with the right equipment...

Okay. With that straight, back to my next spot I'm hung. Temperature. So far, planet #1 is a C-19,000km-1.5-2.25-5. Needless to say, it's a extremely dense planet of compressed metal. It's atmosphere so far is D-5.6-1.8. Since it's extremely close to the star, I know it's going to be crazy hot. But where is temperature actually covered? Using the rules from the core rulebook seem illogical and prone to be wildly off, but I can't find anything in the WBH to cover it.

 

[metlk]

In fact, it's cold as hell

I just now realized you're the author. I can't tell you how awesome it is that you're on here answering questions. Even when there's parts I get frustrated with, I have to say the Mongoose forums are a fantastic place full of people that are super friendly and helpful. Thank you to everyone for taking the time to help me.

 

[Geir]

For temperature, start on Page 108 with Mean Temperature (meaning average, not angry, but I suspect it's going to be pretty hot...) the non-math method is a modification of the the Core rulebook table with the DMs from their (or p. 47 in the WBH) and additional DMs for the Orbit# as indicated. The math 'advanced' version requires a bit more pre-work.

 

[metlk]

I found it. It seems a little out of order since hydrographics are dependent on temperature? Not a big deal now that I know where to look though. I found where I messed up though. I was working under the assumption that I needed to know the temperature to determine if it was a hot or cold planet, but I just found on page 94 how that is determined. I created my atmosphere for a habitable zone, not in the hot zone. I'll clean up my mess and report back when my brain misfires again!

 

[metlk]

That was short lived. When it says HZCO -1.01 to 2.0, is that the the orbit number, such as my first plant is -7 orbits beneath my HCZO, or is it the orbit# as in 0.22, which is only 0.54 less than my HZCO? I keep getting confused on when I should use the orbit slot vs. the actual orbit number. I think it's is a problem of my orbits being so tight combined with zero knowledge of stellar creation, so I have no idea what range I should be expecting. Common sense tells me it should be hot, but unless I am misunderstanding, I just roll on the normal atmosphere table because the "Hot atmosphere" doesn't start until HZCO -1.01. I'm only at -0.54 so it's not considered hot? Then it also say to divide by 10 for an HZCO below 1.0. What am I dividing by 10? The dice result or the orbit#? Neither of those seem to give me a useful result.

I have the same issue with the temperature modifiers. It says if orbit# is less than HZCO-1, then also says to to adhere to divisional differential value translation when HCZO# or Orbit# is less than 1. I know that was probably covered somewhere, but I can't find it. If I assumed that the -1 refers to the orbit# (mine of 0.74) so I just did a straight roll of 5, plus the atmosphere modifier (at the time I thought it was D for +2) which gave me a temp result of 7, or 15 degree. That seemed highly unlikely and which is why I am now questioning my entire atmosphere setup.

 

[Geir]

The temperature should be based on Orbit#s. So if the HZCO is 0.76 and the Orbit# of the planet is 0.22, then you're correct, the difference is 0.54. The thing that is difficult for me to explain (and I'm sorry, but all I can say is it made sense at the time and now I'm flipping through quickly, is that what is being divided by 10 is the actual effect of the distance as it relates to the charts - I'm probably explaining it badly (sorry on lunch break after a night of bad sleep). But here's the general idea: inside a Orbit# of 1.0, effects are magnified so an effect that would normally happen at HZCO - 2.0 Orbit# happens at HZCO - 0.2 Orbit#s (so what's being divided by 10 is the range of the habitable zone), so the difference of 0.54 is effectively HZCO -5.4 Orbit#s as far as the temperature is concerned (in hindsight, I'm not sure why it got explained that way, but maybe if I had time to read all the words, it would make sense again).

So in that case, the atmosphere would be determined off the p. 94 Hot Atmospheres table with the first column: HZCO -2.01 or less and the temperature roll would have a DM based on HZCO -5.4, which is DM+4 +1 per 0.5 Orbit# below HZCO-1(round to nearest), effectively DM+4 +1*(5.4÷0.5 -1 - which is 10.8-1 rounded to 10) so an effective DM of +4+10 = +14 on the 2D roll. It's gonna be hot.

And yes, temperature affects Hydrographics, so it may need to be recomputed based on the Boiling temperature, but if temperature is computed using the formula, then Hydrographics can be a factor - and I have to avoid the loop somewhere and putting require values like Hydrographics before optional ones like temperature seemed to be the way to go. It has a greater effect inside the habitable zone, but if all you're doing is a Mainworld, then it only comes up in a limited number of cases - or you can just assume Hot for the region around HZCO-1 and Boiling for things much below - or with nasty atmospheres - and you'd not likely be wrong after doing the detailed temperature calculations.

Hope this helps.

 

[metlk]

I suspected my orbit# for the calculation should have worked out to having the same effect as -2.2, but that would have required a multiplier instead of a divide and I couldn't figure out how to make it work. Now I see what you meant by dividing the HZ range. It makes sense now that you clarified it, but it might have been clearer to simply multiply the orbit# (although I'm sure there is a reason you went the way you did.) Thank you for helping me through all of this.

 

[metlk]

I managed to make it through the rest of the Class IV survey data except for a couple of parts. I skipped most of the temperature and seismic information. Those were far too math heavy for me so I'll just use a mean temperature and hand waive the rest as needed if it is ever even needed. I still need to figure out AU. The math isn't hard, I'm just not clear in the instructions. When it talks about the difference column, I am not understanding the frame of reference. Do I use the numbers on the Orbit# table as in the example, or do I use numbers from my own orbit# calculations? I don't know what to plug in where since I don't know what my frame of reference for the difference should be. If I guess, I get distance for orbit#1 as 0.4, + the difference of 0.3, x my fractional value of 0.22? That puts it at roughly 0.15 AU? Is that correct?

 

[Geir]

Think of the Distance to be the whole number value of the Orbit# and the Different to be the AU between that whole number value and the next Orbit Number. For instance Orbit#3 has a Distance of 1.0 and a Difference of 0.6, so something in Orbit# 3.5 would have an AU value of 1.0 + 0.6 x the fractional value of the Orbit# (which in this case is 0.5) or 1.3 AU.

 

[metlk]

How do I apply that to my system? My best guess at this point is if my first orbit is orbit#0.11, I multiply by 10 so I get a whole number of 1.1, or orbit#1. If I add the distance and difference from the table I get 0.7, which I then multiply by the fractional value of 0.1 (what was left from converting to a whole number before adding any variance?) for an orbital AU of 0.07? If that's right, do I then need to reduce it back down by 10 so it's actually 0.007 AU?