WBH Belt Bulk Calculation

[Dodo98]

I'm quite confused about the calculation for Belt Bulk on p. 73. The formula clearly says to roll 2D2 + DMs. So far so good. But if I look into the examples on pages 74 and 75 it appears that a formula is used that goes like this: 2D6 +2 + DMs.

In the first example it says: 4+2-6.3/2+2/10. Where is the +2 coming from? It is not in the formula on p. 73.

And in the second example it says: 5+2-6.3/2+20/10. Again we have a +2 DM, and on top of that, a 5 is rolled. That wouldn't be possible with 2D2. So I believe that either the examples are wrong, or worse, the formula printed on p. 73 is wrong.

 

[Limpin Legin]

I suspect the "4+2" from the first example is 1D6 + 1D6, and the D6 digits haven't been converted into D2 numerals. I cannot see how those numbers could have been from an unmentioned DM.
So, while the Belt Bulk formula provided is 2D2 - System Age DM + Composition DM, the actual formula used in the examples probably was D6 + D6 - System Age DM + Composition DM. That must be wrong, by definition. But I see no other way of interpreting the example numbers.

 

[Dodo98]

I suspect the "4+2" from the first example is 1D6 + 1D6, and the D6 digits haven't been converted into D2 numerals. I cannot see how those numbers could have been from an unmentioned DM.
So, while the Belt Bulk formula provided is 2D2 - System Age DM + Composition DM, the actual formula used in the examples probably was D6 + D6 - System Age DM + Composition DM. That must be wrong, by definition. But I see no other way of interpreting the example numbers.

After looking deeper into the rulebook, I've found an 'Asteroid Belt Checklist' on p. 248. It confirms that the formula on p. 73 should be 2D +2 + Other DMs. 2D6 +2 is a pretty significant difference compared to 2D2.

 

[Limpin Legin]

2D6 is a pretty significant difference compared to 2D2.

It is if they don't convert the D6 scores into D2 values, as instructed on page 4.

 

[Dodo98]

It is if they don't convert the D6 scores into D2 values, as instructed on page 4.

It is very confusing. Both options could work. But only the author will be able to give a definitive answer. How can we reach him?

 

[Limpin Legin]

Both options could work. But only the author will be able to give a definitive answer. How can we reach him?

@Geir should reach the author . Since today is New Year's Day they might be away on annual leave. You may need to wait for a reply.

 

[Dodo98]

@Geir should reach the author . Since today is New Year's Day they might be away on annual leave. You may need to wait for a reply.

Thanks!

 

[Geir]

Bug. I wrote it as:

Belt Bulk = 2D +2 +DMs

But the first "+" is missing from the published text. Good catch. I'll add it to my list of known errata.

 

[Dodo98]

Bug. I wrote it as:

Belt Bulk = 2D +2 +DMs

But the first "+" is missing from the published text. Good catch. I'll add it to my list of known errata.

Thank you for confirming my suspicion.

Will the known errata be published sometime in the near future?

 

[Dodo98]

@Geir Sorry but I have another question, although this time it's just me being stupid I guess. But I can't seem to figure out how to properly do the atmosphere, hydrographics and temperature determinations. I want to do the advanced temperature calculation by formula. To do that I need the albedo und greenhouse factor. Okay, but to determine the albedo I need the Hydrographics. But that value is dependent on knowing the temperature (or at least if the world is considered hot or boiling). But the only way to know that is the table on p. 47, correct? And to use that table I first need to determine the atmosphere. But atmosphere also needs the temperature for some of it's calculations, especially to check for a runaway greenhouse.

I'm sure it's a pretty straightforward process and I'm just not grasping it right now, but I'm pretty confused by now: hydrographics are depending on temperature, temperature is depending on albedo, and albedo is depending on hydrographics... Could you tell me the correct order in which I should perform the calculations so that I can then calculate the temperature using the formula?

 

[Geir]

@Geir Sorry but I have another question, although this time it's just me being stupid I guess. But I can't seem to figure out how to properly do the atmosphere, hydrographics and temperature determinations. I want to do the advanced temperature calculation by formula. To do that I need the albedo und greenhouse factor. Okay, but to determine the albedo I need the Hydrographics. But that value is dependent on knowing the temperature (or at least if the world is considered hot or boiling). But the only way to know that is the table on p. 47, correct? And to use that table I first need to determine the atmosphere. But atmosphere also needs the temperature for some of it's calculations, especially to check for a runaway greenhouse.

I'm sure it's a pretty straightforward process and I'm just not grasping it right now, but I'm pretty confused by now: hydrographics are depending on temperature, temperature is depending on albedo, and albedo is depending on hydrographics... Could you tell me the correct order in which I should perform the calculations so that I can then calculate the temperature using the formula?

Of course reality is complicated and might be a multi-pass feedback loop causing a runway greenhouse*, but... for our purposes, the first pass numbers on page 47 for temperature based on HZ location and Atmosphere type can be used to set the 'initial temperature' to determine if the hydrosphere takes a hit. It sort of implies so in the second paragraph under Hydrographics on page 99.

A point-in-time linear process is all this is process able to accomplish, so I'd only adjust Hydrographics at most once (per page 47) and then use that value for the albedo modifiers. The runaway greenhouse check is the hack to avoid having to the process in a loop.

*Long ago, I did a program to determine temperature based on atmosphere, with subroutines calling subroutines and, well, I had to add a counter to break out of the loop after 50 passes, because every once in a while, it flipped back and forth around threshold values. Forever. Or forever on an 8086 processor, anyway.

 

[CordwainerFish]

And now I'm wishing I'd had more DiffEq in college. Not that I'd remember any of it by now.

 

[Dodo98]

Of course reality is complicated and might be a multi-pass feedback loop causing a runway greenhouse*, but... for our purposes, the first pass numbers on page 47 for temperature based on HZ location and Atmosphere type can be used to set the 'initial temperature' to determine if the hydrosphere takes a hit. It sort of implies so in the second paragraph under Hydrographics on page 99.

A point-in-time linear process is all this is process able to accomplish, so I'd only adjust Hydrographics at most once (per page 47) and then use that value for the albedo modifiers. The runaway greenhouse check is the hack to avoid having to the process in a loop.

*Long ago, I did a program to determine temperature based on atmosphere, with subroutines calling subroutines and, well, I had to add a counter to break out of the loop after 50 passes, because every once in a while, it flipped back and forth around threshold values. Forever. Or forever on an 8086 processor, anyway.

Thanks, I think this will get me on the right track.

By the way, I really enjoy your book. You did a great job with it. But if you ever consider publishing a second edition, I would highly recommend including a flowchart for a better overview. Yes, there is a checklist at the end of the book, and it's not bad, but some of the steps are a bit confusing if you're not yet familiar with the subject matter, and I think a visual representation would help a lot of people.