I swear, sometimes my muse has the attention span of a squirrel.
My plan for March was to release a new minor update to the Architect of Worlds partial draft, and then write several more chapters of The Sunlit Lands so I could send out a good-sized chunk of that as a charged release for my patrons.
Architect of Worlds did get bumped up to Version 0.4 as of last week – a bunch of tweaks, some of them substantive, many of them driven by the flood of good feedback I’ve received from Brett Evill since the beginning of the year. With that out of the way, I was all set to buckle down and concentrate on The Sunlit Lands. I expected to be finished through Chapter Six or Seven and about 20,000 words by the end of March.
Meanwhile, I posted a couple of weeks ago about an old Traveller project, the Game of Empire rules that I originally developed about twenty years ago. At some time in the near future, I intend to revisit that project and produce a new version of those rules, possibly working toward publishing them as a paid product on DriveThruRPG. I hadn’t intended to work on that just yet, though – Krava’s story was calling me!
Yet early this week, I got the first hint of an idea for a Traveller setting that could act as a test-bed for Game of Empire. It’s a “Milieu Zero” concept of sorts, a single world striving to establish a new interstellar empire after a Long Night. Every day, while I worked on projects for my day job and made progress with Krava’s story, the Traveller idea kept growing in the back of my head, grabbing hold and not letting go.
Today I sat down to try to jot down some notes and get it out of my system, so I could get back to work on Krava . . . and new material just poured out onto the page. Over 3,000 words of it since I got up this morning. Not to mention that I’ve already come up with at least two or three ideas for short fiction, attached to this setting.
Well. I know not to argue when my muse is at work. Even if I wish she were more consistent.
Apparently, by the end of March, I’m going to have something new and worth sharing, it just isn’t going to be enough of The Sunlit Lands to meet my objective. Nor will this block of new Traveller material be useful as a charged release, since I’d like to share it widely and attract some attention to the potential project.
So here’s the (revised) plan for the last few days of March:
There will be no charged release for my patrons this month. (Again.)
I should have about 5-6000 words of new Traveller material that will be posted here, shared with my patrons, and possibly shared via social media as well. This will be a free release.
I still need to finish and publish a book review for the month of March. I’ve already selected and read the book, I just need to bang out the review.
We’ll see if April goes any differently. At least I seem to have gotten out of the creative slough I was mired in for most of February and the first week or so of March. There’s a good chance I’ll be able to produce a worthwhile amount of material next month.
A quick note today, to lay out my plan for the rest of this month. I seem to have pulled out of the creative slump I’ve been wrestling with for most of the last six weeks, so I want to strike while the iron is hot.
I’m currently working on a new minor update of the Architect of Worlds design sequence, which should start to reflect some of the feedback I’ve gotten from my patrons since the January release, and otherwise make some incremental improvements. I’m working on including a change log in this version, so people who are working with the most current draft know where the most recent tweaks are. The plan is to have this new version ready by Thursday at the latest, at which point I’ll send that to my patrons as a free update.
I’m also focusing on getting some more of the rough draft of The Sunlit Lands written, and if I can get to at least 15-18 kilowords of coherent material, that will be this month’s charged release for my patrons.
I’m also working through my backlog of book review requests, so I hope to have one or two more reviews out before the end of this month.
Those are my “must accomplish” items for March. Stay tuned.
The last few weeks have been a bit of a ride, so I have a few updates for everyone.
First, for some time now I’ve been dealing with some minor medical issues, and that seems to have come to a head in the month of February. Nothing life-threatening, by any means, but it was kind of hard on my productivity. Chronic headaches, lethargy, inability to focus or keep on task well into each day. I was having a hard time keeping up with work for my day job, much less my creative projects.
It turns out that my treatment regimen for type-2 diabetes has been throwing me for a loop.
Ironically, my lifestyle has been a lot healthier ever since the COVID-19 pandemic crashed down on us. I’m getting more exercise, my diet is much better, I’ve lost a significant amount of weight, and so on. However, until recently I hadn’t adjusted my medication routine to fit, and it’s looking as if my blood sugar was becoming chronically low in the mornings. Again, not low enough to be a serious threat, but more than low enough to account for the difficulties I was having.
The good news is that this is all correctable. Now that I understand the problem, I’m adjusting my treatment regimen, within parameters approved by my physician, and I’m hopeful that I’ll be able to recover my mornings.
The bad news is that working on this has taken up most of the month of February, with the result that I haven’t hit several of my goals, and probably won’t before the end of the month.
As a result, there will be no charged release or bonus release for my patrons this month. I also don’t think there will be any updates to Architect of Worlds or the Human Destiny draft sourcebook until sometime in March.
That having been said, here’s a summary of the creative projects I have under way at the moment, roughly in order of priority:
Book reviews, still at the rate of one or two a month.
An update for Architect of Worlds, revising some of the existing material and possibly adding a new section (on the subject of “using real-world astronomical data”).
Further progress on The Sunlit Lands, the second book in the Krava’s Legend series.
An update for the Human Destiny draft sourcebook, with some new material.
Development for a new book-length project, building “A Fire in Winter” out into a novel-length collection of short stories. More about that in an upcoming post.
Re-evaluation of The Master’s Oath, with an eye toward giving it an extensive rewrite and preparing it for eventual publication.
I’m also starting to think about how to improve my strategy for publishing and promoting my work. Sales of The Curse of Steel have been kind of disappointing – after an initial surge when the book was published, they’ve faded down to essentially zero since the new year. I’ve tried a few things to promote the book, with very ambiguous results. In the meantime, I’ve gotten hooked into one or two communities of self-published authors, and have been learning a lot about ways to improve presentation and promotion.
Within the next few months, I’m likely to have another book to publish, even if that isn’t The Sunlit Lands. I’m going to take that opportunity to prepare and apply a more aggressive publication strategy. If that works, I may go back and re-launch The Curse of Steel, using some of what I’ve learned. This is a long-term investment, but with luck, it will pay off.
Soon after I stopped spending most of my creative effort on work for the tabletop game industry, I started work on what would eventually become my first mature, original, and complete novel. Its title was The Master’s Oath, and it will never be published.
When I finished working for Steve Jackson Games, I still had a lot of that company’s influences in the back of my mind. In particular, a book Ken Hite had written for GURPS in 2001 (GURPS Cabal) made quite an impression on me. It was that book that made me aware of the Western esoteric traditions for the first time: kabbalah, Hermeticism, Johannes Trithemius, Heinrich Cornelius Agrippa, the Tarot, the Golden Dawn, that whole utterly snarled yet gorgeous ball of yarn. I studied esoterica for years afterward, building quite the library of relevant works, all of which are still in my possession.
Mind you, I’m not by any means a believer or a practitioner. The Western occult tradition was a false trail in our intellectual history, not something that has any pragmatic reality. I still find it useful as a source of creative inspiration. To this day, the attentive reader might notice little scraps of it in my fiction – alchemical or Tarot imagery, that kind of thing.
The Master’s Oath was one product of that period of my life. It was an alternate-history novel, a portal fantasy too, with Golden Dawn-style magic built into the plot. I worked on it from about 2008 through 2012, and that was a fierce and terrible struggle. I learned a lot about planning and writing long-form fiction, about world-building in the service of literary work, about a lot of things not to do. I don’t regret that time spent.
On the other hand, as I mentioned, The Master’s Oath is utterly unpublishable, a fact I only realized after I had congratulated myself on finally finishing my first mature original novel. I’m still proud of the research, the world-building, the quality of the prose in it. Unfortunately, it’s also a deeply problematic piece of work . . . not outright racist, as such, but thoroughly insensitive, with tropes built in that an American White male author really needs to be very careful about. Much more careful than I knew how to be at the time. Probably more careful than I have the skill for even today. So I’ve chalked The Master’s Oath up as part of the “million crappy words” that every novelist probably has to write before he can start making real progress.
Still. Nothing a writer ever learns is likely to go to waste forever. I still have all that esoterica lurking in the back of my head, along with everything I’ve learned as a Freemason, and whole reams of early-modern history.
Finally, I think I may have discovered a way to put all of it to use.
Imagine a world that diverges slightly from our own about the time of Elizabeth I, and becomes significantly different sometime in the early eighteenth century. A world where people like John Dee, Michael Maier, Robert Fludd, and Elias Ashmole were really on to something. A world where the Rosicrucian movement wasn’t just a weird historical joke.
A world in which different ideas and different historical currents might give rise to a different kind of modernity. A different kind of United States, in fact. Maybe even a better one.
As always, when I’m tinkering with alternate-historical ideas, my first impulse is to bring a few games to the tabletop out of my extensive library of historical simulations. For example:
Imperial Struggle is one of the most recent purchases in my library, a grand-strategic simulation of the conflict between Britain and France in the long eighteenth century. Its mechanics are deceptively simple, but the resulting gameplay is deep, rich, and nicely balanced – a great tool for developing alternate histories.
Here’s another one, ironically the very first historical simulation game I ever owned:
1776 is a much older game – my copy has been on my shelves for well over forty years now – but it’s a decent simulation of the American theater of a war that was fought across half the world, and ended with the formation of the United States. It’s nicely customizable too, easy to build alternate-historical scenarios for.
I can think of two or three other games I might be able to bring down and use, too. I have more than enough material to start building a timeline and a “bible” for stories set in this putative alternate reality.
As for the stories themselves? Well, “A Fire in Winter” fits nicely into the emerging structure. In fact, thinking about what else I could write to follow that story is probably what got my hindbrain working on this notion. I’m sure that as I start writing down and organizing all of this, more stories will suggest themselves.
None of which means I’m going to be setting aside other projects, to be sure. I still need to keep making progress with Architect of Worlds, the Human Destiny setting, and The Sunlit Lands. Still, I’ve been in a bit of a rut for the last few weeks, and my creative brain seems to work better when I can shift to a new project once in a while. This may be a promising candidate.
The past two weeks have been just about a wash for my creative work. A task at my day job pushed aside just about everything else for about a week and a half. Then, just as that was winding up, I took a nasty fall outside my house and got rather banged up. Nothing was broken and I didn’t need a trip to the hospital, thank goodness, but I collected a fair number of gouges, scrapes, and bruises. I’ve been in a fair amount of discomfort for several days. Kind of hard to focus on creative work, especially since my dominant hand is one of the parts that are stiff and sore. At this point, I’m not likely to hit some of the creative milestones I had in mind for this month.
Not all the news is bad, to be sure. I’d like to praise a couple of my readers, Brett Evill and K. Nakamura, for their work “playtesting” and providing feedback on the current Architect of Worlds draft. The two of them have been going through the current sequence with a fine-toothed comb, and they’ve already found a number of things that could stand to be fixed or improved. I plan to get back to that project in February and will probably be releasing a new minor version to my patrons fairly soon.
Another piece of the Architect of Worlds project will involve writing some material on how to use real-world astronomical data with the design sequence. If you want to build a realistic “solar neighborhood” for your SF setting, incorporating what we know about the stars and exoplanets around us, how do you go about that? I’ll probably at least start working on that next month too.
Meanwhile, since I had more than enough hours on the books at my day job, I’m taking the rest of January off to heal up from my accident and get some writing done. I’m focusing on producing a new partial draft of the Human Destiny sourcebook for Cortex Prime. Right now that’s at about the 16-kiloword mark, and I’m hoping to get a few thousand more words down before the end of the month.
The partial draft of the Human Destiny sourcebook will be this month’s charged release for my patrons. Once that’s out, they’ll get free updates as I continue to work on the project, until the rough draft is completed.
I don’t have any new original fiction to release this month, although I’m considering dressing up a bit of work from my fan-fiction period to show off. I’m also reading a very good candidate for my next book review.
Finally, I’m continuing to make slow progress on The Sunlit Lands, which will be the first sequel to The Curse of Steel. No clue yet when that novel will be finished, but at the moment I’m hoping to release it late in 2021.
The name of the game is persistence and resilience . . .
Man, this month is just flying past. There’s a lot going on, and I’ve just about committed myself to a plan for this month’s Patreon release, so it’s time for a general update.
Architect of Worlds: I’ve been stress-testing the current draft of the complete design sequence (version 0.3, which was released to my patrons on 5 January). I’ve found a few minor bugs and tweaks, and possibly some ideas for further development, but nothing that requires major surgery at this point. Along the way, I’ve started developing a new map and gazetteer of the solar neighborhood for the Human Destiny universe. That’s probably going to take quite a while to complete.
Human Destiny: Back in December I completed a partial rough draft of the proposed Cortex Prime sourcebook, as a submission for the Cortex Creator’s workshop. I’ve gotten some useful feedback from that, and I’ve started to write some more new material for this project.
Short Fiction: I don’t think I’m going to release any free new short fiction in January. This is because I appear to be on the verge of actually selling two pieces of short fiction! I need to concentrate on writing material that will actually earn me some income. More about that if and when the deal is completed.
Krava’s Legend: I didn’t get much work done to promote The Curse of Steel in November or December, nor did I get much written on The Sunlit Lands. I’m trying to carve out some time to keep pushing forward with those tasks.
Book Reviews: Since this blog has been listed on a couple of sites for independent book reviewers, I’ve been getting lots of requests for reviews. More than I’ll be able to cover, although that’s not a bad problem to have. At the moment it looks like I’ll be covered for January and February – look for two or three new reviews here over the next few weeks.
Okay, now for patron’s business.
I’m going to institute a new procedure for certain big projects, the kind that are likely to be in development for several months with incremental drafts. It’s in my interest to let my patrons see early drafts, because I might get useful feedback. On the other hand, I’m not comfortable charging my patrons every month for access to the latest versions.
So in such a case, I’ll be charging my patrons in the first month that I release a draft, but subsequent incremental updates will be free to patrons until the draft is more or less complete and ready for publication. (Also, of course, patrons at the appropriate level of support will get a free copy of the finished product, if and when that’s ready.)
The first project to fall under this heading is the current version of the complete design sequence for Architect of Worlds. I released version 0.2 of that in December as a charged release. I updated the document to version 0.3 in early January and will continue to release the occasional incremental update to my patrons as needed. Those incremental updates will be free of charge.
The second project that will come under this heading is the rough draft of the Cortex Prime sourcebook (and setting bible) for the Human Destiny universe. I’ll be releasing a partial draft (version 0.2) to my patrons late in January, which will be this month’s charged release. Subsequent incremental updates to that document will be free of charge.
Haven’t decided what I’ll be releasing in February, but honestly, there’s a lot going on that’s not entirely under my control at the moment. I’m playing things by ear for now. More news as I figure things out.
For those who are interested in the Architect of Worlds project, here’s a quick summary of its status.
After several years of sporadic work, I finished the first complete version of the design sequence just before Christmas. Over the next couple of weeks, I did some intensive testing and made two pretty significant revisions.
At the moment I have a partial draft of the book that’s in an “alpha release” state (Version 0.3), covering just the sequence for designing star systems, planetary systems, and individual worlds. It works – I’ve been generating a series of plausible and often weirdly interesting worlds with it.
My readers should be aware that this is not the version that’s currently posted to the Architect of Worlds page on this blog. That’s Version 0.1, the first complete sequence, before the last two rewrites. That version works too, but there are some problems with it – you may not want to lean on it too hard. I’m considering taking it down entirely.
As of right now, the best way to get your hands on the current release draft is to sign up for my Patreon (see the link in the sidebar). I anticipate having a complete draft of the book ready for release sometime this year, so at this point, the project is moving out of the “free to the public” phase.
The article was from the Niels Bohr Institute, summarizing some research done there by Nanna Bach-Møller and Uffe G. Jørgensen. The upshot is that, based on our extensive sample of detected exoplanets, we can conclude that there’s a fairly strong correlation between the number of planets in a planetary system and the average eccentricity of the orbits of those planets. “Just a few planets” seems to correlate to highly elliptical orbits, while “more planets” means closer-to-circular orbits.
It makes sense. We know a lot more about the process of planetary formation than we did even twenty years ago. That process appears to be pretty chaotic. Planets sometimes interact a lot while they’re forming, with unpredictable results. Sometimes that interaction leads to some of the young planets getting “pumped” into highly eccentric orbits, but that also leads to more of them being “ejected” from the planetary system entirely. So it makes sense that planetary systems that end up with fewer planets might also see those planets line up into more eccentric orbits.
The article claims that our own planetary system is unusual in that we ended up with more planets than the average. As a corollary, it shouldn’t be a surprise that the planets we still see have settled into a well-behaved stack of nearly circular orbits.
Okay. The article was interesting enough. The problem was that the actual research paper behind it was sitting behind a paywall. I put off reading that until after I had finished the rough draft of the Architect of Worlds design sequence. Maybe then I would track down a copy, and it might suggest a way to improve the step in which I assign orbital eccentricities. Not a big deal.
Well, I finished the rough draft just before Christmas, and yesterday I found a way to get a copy of the paper for a reasonable fee. I sat down to read it, and . . .
Bach-Møller and Jørgensen have done something a little more remarkable than I expected. They haven’t just derived a strong correlation between planetary multiplicity and eccentricity of orbits. They’ve demonstrated that we can derive a clear power law for how many total planets a given system has, including the ones we can’t detect yet, just based on the observed eccentricity of the ones we can detect.
Applying this result to my models in Architect of Worlds, I find that I can do a lot more than just superficial improvement to one step of the system design process. I can actually rework several of the steps in the sequence, making them simpler and easier to use, and also making them line up a lot better with the current state of exoplanetary science.
The executive summary is that instead of laying down planets until you run into any of several limiting conditions, you randomly generate the total number of planets first, and then place that many. Much simpler, and it fixes the problem that the current version seems to generate too many planets.
This isn’t a small improvement. We’re talking about eliminating several of the most cumbersome computations and procedures, while also forcing the outcome to match observed results much more closely. I can’t really let that sit in the idle stack, especially since I have a couple of other projects that are dependent on having a complete draft here.
One complication is that one of those other projects was something I was planning to put together for my patrons, as a charged release, before the end of December. Although I think I see how to make all the necessary changes to the Architect of Worlds draft, that’s going to take a day or two of work, and I have a pile of other things to get finished over the next few weeks as well.
So here’s a revision to my creative plan for the next couple of weeks:
The top priority right now is to revise the partial Architect of Worlds draft to fit these new results. This should be complete no later than 28 December. At that point, I will release a revised version of all of the completed sections of the draft, for my patrons only (with one or two exceptions for non-patrons who have been helping out with extensive comments on the draft). That will constitute my charged release on Patreon for December 2020.
The PDFs that are already on the Architect of Worlds page will remain there. Those won’t constitute the most up-to-date version, but they are certainly “playable” for anyone who wants to experiment with them. I won’t be updating those PDFs for at least three months. During that time, I’ll continue to polish and tweak the system with input from my patrons, and possibly work on some additional material. I’ll reassess the situation in early April. By then I may be within striking distance of starting to prepare a publication-ready draft of the entire book. If not, then I’ll create and post new PDFs at that point.
By the end of December, I need to write a new book review, and also finish and release another piece of short fiction. Those will be posted here and released to my patrons for free. I also need to get started on a new piece of short fiction (more about that later).
Once all of the above is finished – probably over the New Year’s holiday – I’ll take stock. That’s a traditional time for such things anyway.
As of today, the rough draft of the design sequence for Architect of Worlds is finished. Merry Christmas to me!
I’ve posted a PDF for the third chunk of the design sequence, “Designing Planetary Surface Conditions,” to the Architect of Worlds page on this site. That chunk includes everything from Step 15 (Orbital Period) through Step 27 (Components of Atmosphere) in one document, with a few minor tweaks and corrections from the version that was first posted to this blog.
Together with the earlier sections already available there, this makes up about 37,000 words of carefully researched and somewhat technical world-building tools, available to the public for free for now.
There’s a lot more work to be done before this is a completed book, ready for publication. I intend to write plenty more material:
How to work with real-world star maps
How to read and use real-world astronomical data from star catalogs and lists of known exoplanets
Tips for planning interstellar settings, and placing interstellar societies on the map
Sidebars for a bunch of special cases (planets that circle pairs of stars, planets of stars that aren’t on the main sequence anymore, planets of brown dwarfs, more exotic things to place on your star maps, odd circumstances that might pop up on planetary surfaces, and so on)
General world-building advice, including ways to use and make sense of the results of the design sequence
Not to mention going through the whole sequence at least one more time, to double-check all my research, footnote everything, and see if I can make the system easier to use in a few places. Probably with some intensive testing on real-world data to support one or two other projects.
Still. There’s at least a good chance that the first full edition of Architect of Worlds will be available for sale sometime in 2021. Probably later rather than sooner, but we’ll see how it goes.
Architect of Worlds – Step Twenty-Seven: Determine Details of Atmospheric Composition
In this step, we will work out the implications of several of the preceding steps for the composition of the world’s atmosphere. In most cases, this will depend solely on the atmospheric class (from Step Twenty-Three). However, in the case of a Class III (Earth-type) atmosphere, we will also use quantities developed in Steps Twenty-Five and Twenty-Six to determine some of the details. This will be useful in determining whether a given Earth-like world’s atmosphere is comfortably breathable for humans – or for invented aliens.
Procedure
Apply the appropriate case from the following.
Class I Atmosphere
A Venus-type atmosphere will be composed almost entirely of carbon dioxide, very hot and at immense pressures. It will also contain a small portion of nitrogen, and traces of other compounds such as sulfur dioxide. Exposure to such an atmosphere will be almost instantly fatal to human life.
Class II Atmosphere
A Titan-type atmosphere will be composed almost entirely of nitrogen, with a small portion of methane and traces of other compounds, such as carbon dioxide and various hydrocarbons. The atmosphere itself is likely to be suffocating to human life, but not actively toxic.
Class III Atmosphere
We will deduce the details of an Earth-type atmosphere from other elements of its surface conditions.
Begin by making a note of the total atmospheric mass as determined in Step Twenty-Three. Then, after determining the partial atmospheric mass taken up by each of the following components, subtract that quantity from the total atmospheric mass, so as to keep a running tally of how much of the atmospheric mass remains to be accounted for.
Also, make a note of the total greenhouse effect as determined in Step Twenty-Five. After determining how much of this greenhouse effect can be attributed to each atmospheric component, subtract that quantity from the total greenhouse effect, keeping a running tally of how much of the greenhouse effect remains to be accounted for.
Water Vapor
A world’s atmosphere will contain a significant amount of water vapor (H2O) if it has Moderate, Extensive, or Massive prevalence of water, and its average surface temperature is at least 251 K. If either of these conditions fails to hold, skip this component.
To determine the atmospheric mass taken up by water vapor, refer to the following table:
Water Vapor Table
Average Surface Temperature
Multiplier
251-260 K
0.001
261-270 K
0.002
271-280 K
0.003
281-285 K
0.004
286-290 K
0.005
291-295 K
0.008
296-300 K
0.010
301-305 K
0.014
306-310 K
0.019
311-315 K
0.025
316-320 K
0.035
321 K or higher
0.050
Multiply the total atmospheric mass by the multiplier from the table for the world’s average surface temperature. Then multiply the result by 0.8 (for Extensive prevalence of water) or by 0.3 (for Moderate prevalence of water). The result is the partial atmospheric mass of water vapor for the world.
To compute the greenhouse effect caused by this water vapor, evaluate the following:
Here, G is the greenhouse effect due to water vapor in kelvins, and M is the partial atmospheric mass of water vapor as determined above. Round G to the nearest kelvin (minimum 0).
At this point, round M to the nearest thousandth, then subtract M and G from the running tally of atmospheric mass and greenhouse effect before moving on to the next component.
Methane
A world’s Class III atmosphere may contain methane (CH4) in trace amounts if it has life. Even very primitive life forms generate some methane, in tiny amounts compared to the whole volume of a world’s atmosphere. However, methane is a very effective greenhouse gas, so even traces of it can cause measurable warming.
A world’s atmosphere will contain a significant amount of methane if it has undergone abiogenesis, either in deep hydrothermal vents or on the surface (see Step Twenty-Six). If this condition fails to hold, skip this component.
To estimate the greenhouse effect caused by methane, evaluate the following:
Here, G is the greenhouse effect due to methane in kelvins, and M is the total atmospheric mass for the world. Round G to the nearest kelvin (minimum 0).
At this point, subtract G from the running tally of greenhouse effect before moving on to the next component. The actual atmospheric mass of methane will always be insignificant.
Ozone
A world’s Class III atmosphere will contain ozone (O3) in trace amounts if it has significant free oxygen. Ozone is formed in the upper atmosphere when molecular oxygen (O2) is exposed to the primary star’s ultraviolet radiation. Ironically, the “ozone layer” then blocks much of that ultraviolet from reaching the world’s surface. The presence of an ozone layer may be a requirement before multicellular life can safely colonize exposed land. As with methane, ozone is a very effective greenhouse gas, so even traces of it can cause measurable warming.
A world’s atmosphere will contain a significant amount of ozone if it has undergone an Oxygen Catastrophe (see Step Twenty-Six). If this condition fails to hold, skip this component.
To estimate the greenhouse effect caused by ozone, evaluate the following:
Here, G is the greenhouse effect due to ozone in kelvins, and M is the total atmospheric mass for the world. Round G to the nearest kelvin (minimum 0).
At this point, subtract G from the running tally of greenhouse effect before moving on to the next component. The actual atmospheric mass of ozone will always be insignificant.
Carbon Dioxide
All of the remaining greenhouse effect on this world will be attributable to carbon dioxide (CO2) in the atmosphere. Carbon dioxide is a common component of planetary atmospheres, generated through volcanic activity or the oxidation of organic matter. Carbon dioxide is not a very strong greenhouse gas, but it often exists at much higher concentrations than either methane or ozone, so it is usually the largest or second-largest contributor to a world’s greenhouse effect.
To estimate the partial atmospheric mass of carbon dioxide, evaluate the following:
Here, M is the partial atmospheric mass of carbon dioxide, and G is the remaining greenhouse effect in kelvins after the contributions from water vapor, methane, and ozone have been accounted for. Round M off to the nearest thousandth.
At this point, all of the world’s greenhouse effect has been accounted for. Subtract M from the running tally of atmospheric mass before moving on to the next component.
Molecular Oxygen
If the world has photosynthetic life, then a portion of the atmosphere will be made up of free molecular oxygen (O2).
If the world has photosynthetic life, but has not gone through the Oxygen Catastrophe, then estimate the amount of molecular oxygen by rolling 3d6, multiplying by 0.002, and then multiplying by the total atmospheric mass. Round the result off to the nearest thousandth.
If the world has gone through the Oxygen Catastrophe, then estimate the amount of molecular oxygen by rolling 3d6+15, multiplying by 0.01, and then multiplying by the total atmospheric mass. Round the result off to the nearest thousandth.
In either case, the result will be the partial atmospheric mass of molecular oxygen. Subtract that figure from the running tally of atmospheric mass before moving on to the next component.
Helium
A world whose M-number (computed in Step Nineteen) is 4 or less will have helium (He) in its atmosphere, left over from the world’s original formation. To estimate the amount of helium, roll 3d6, multiply by 0.025, and then multiply by the total atmospheric mass. Round the result off to the nearest thousandth.
The result will be the partial atmospheric mass of helium. Subtract that figure from the running tally of atmospheric mass before moving on to the next component.
Argon
Almost every world with a Class III atmosphere will have some argon (Ar) in its atmosphere, almost all of it generated by the decay of radioactive isotopes in the lithosphere. To estimate the amount of argon, roll 3d6, multiply by 0.001, and then multiply by the total atmospheric mass. Round the result off to the nearest thousandth.
The result will be the partial atmospheric mass of argon. Subtract that figure from the running tally of atmospheric mass before moving on to the final component.
Molecular Nitrogen
The remainder of the world’s atmosphere will be made up of molecular nitrogen (N2), possibly with a few traces of other, more exotic non-greenhouse gases. Make a note of the remaining atmospheric mass, rounding off to the nearest thousandth. The result will be the partial atmospheric mass of molecular nitrogen.
Feel free to list all of the atmospheric components determined above, in order by partial atmospheric mass. This list will give you or your readers a quick way to determine how congenial the atmosphere is for human use.
Converting Partial Atmospheric Masses to Partial Pressures
To determine the partial pressure (in atmospheres) for any atmospheric component at a world’s surface, multiply the partial atmospheric mass for that component by the world’s surface gravity.
Evaluating Human Breathability
In order for humans to comfortably breathe an atmosphere, it must meet all of the following criteria:
Molecular oxygen at a partial pressure of 0.190 to 0.240 atmospheres. Below this range, a respirator is required. Above the range, a filter or “reducing respirator” will be needed.
Carbon dioxide at a partial pressure no higher than 0.015 atmospheres. Above this range, humans will suffer respiratory difficulties and may need a filter.
Molecular nitrogen at a partial pressure no higher than about 4 atmospheres. Above this range, humans will suffer from nitrogen narcosis and eventually lose consciousness. A filter or reducing respirator will be required.
The other likely components of a Class III atmosphere are unlikely to have any toxic or suffocating effect, as long as the above criteria are all met.
Class IV Atmosphere
A Mars-type atmosphere will be composed almost entirely of carbon dioxide, with traces of nitrogen, argon, and other compounds. The atmosphere itself will be extremely thin and suffocating to human life, almost as bad as high vacuum, but it will not actively toxic.
Class V Atmosphere
A Luna-type atmosphere is vanishingly thin and may be composed of whatever particles of the interplanetary medium happen to be captured in the world’s gravity well at the moment. It will be an effective vacuum, quickly fatal to exposed human life.
Examples
Both Arcadia IV and Arcadia V have Class III atmospheres, so Alice prepares to work through the process for each of them. She is hoping that the atmosphere of Arcadia IV will turn out to be human-breathable. The atmosphere of Arcadia V will almost certainly not be, since the planet has no native life, but she will see what results occur for the sake of completeness.
Arcadia IV
This planet has a total atmospheric mass of 0.900, and a total greenhouse effect of 32 kelvins. Alice begins to work through the list of potential atmospheric components.
Water Vapor: Alice refers to the Water Vapor table and determines that the multiplier will be 0.005. She multiplies the total atmospheric mass of 0.9 by 0.005 and then by 0.8 (for the world’s Extensive water) for a partial atmospheric mass of 0.0036. Using the equation to determine the greenhouse effect due to water vapor, she finds that it comes to 21 kelvins (rounded off). She rounds the partial atmospheric mass of water vapor off to the nearest thousandth and corrects her running tallies. She now has atmospheric mass of 0.896 and greenhouse effect of 11 kelvins to account for.
Methane: Arcadia IV definitely has life, so there will be traces of methane in the atmosphere. Using the equation, she estimates that 2 kelvins of the greenhouse effect will be due to this greenhouse gas. She corrects her running tallies, and now has atmospheric mass of 0.896 and greenhouse effect of 9 kelvins to account for.
Ozone: Arcadia IV has gone through the Oxygen Catastrophe, so there will be traces of ozone in the atmosphere. Using the equation, she estimates that 1 kelvin of the greenhouse effect will be due to this greenhouse gas. She corrects her running tallies, and now has atmospheric mass of 0.896 and greenhouse effect of 8 kelvins to account for.
Carbon Dioxide: The 8 kelvins remaining of greenhouse effect implies a partial atmospheric mass of 0.004 of carbon dioxide, about the same amount by mass as found in Earth’s atmosphere. Alice updates her tally of atmospheric mass, finding that she still has 0.892 to account for.
Molecular Oxygen:As already noted, Arcadia IV has already gone through the Oxygen Catastrophe. Alice rolls 3d6+15 for a total of 28, multiplying this by 0.01 and then 0.9 to get a partial atmospheric mass of 0.252. She updates her tally of atmospheric mass, finding that she still has 0.640 to account for.
Helium: The planet’s M-number is 5, so there will be no significant helium in the atmosphere. Alice skips this component.
Argon: Alice rolls 3d6 for a total of 16, multiplies that by 0.001 and then 0.9, and rounds the result off to 0.014 for the partial atmospheric mass of argon. She updates her tally of atmospheric mass and still has 0.626 to account for.
Molecular Nitrogen: The last 0.626 of atmospheric mass will be composed of molecular nitrogen and traces of other non-greenhouse gases.
Alice multiplies all of these partial atmospheric masses by the planet’s surface gravity of 1.05, and arranges them in order from largest to smallest:
Molecular Nitrogen: 0.657 atmospheres
Molecular Oxygen: 0.264 atmospheres
Argon: 0.015 atmospheres
Carbon Dioxide: 0.004 atmospheres
Water Vapor: 0.004 atmospheres
The atmosphere of Arcadia IV looks reasonably close to human-breathable, although it actually has a little too much oxygen in the mix. Humans living there may be able to breathe without assistance for a while, and may even find the air exhilarating, but they are likely to suffer various forms of oxygen toxicity over the long term. The oxygen-rich atmosphere might also encourage fires.
Arcadia V
This planet has a total atmospheric mass of 0.700, and a total greenhouse effect of 17 kelvins. Alice begins to work through the list of potential atmospheric components.
Water Vapor: The planet’s average surface temperature is only 221 K, well below the minimum to have any significant water vapor in its atmosphere. Alice skips to the next component.
Methane: Arcadia V has no native life, and so no significant amount of methane.
Ozone: Arcadia V has no photosynthetic life and so no ozone.
Carbon Dioxide: Apparently the planet’s 17 kelvins of greenhouse effect are entirely due to carbon dioxide in the atmosphere. That amount implies a partial atmospheric mass of 0.033. Alice updates her tally of atmospheric mass, finding that she still has 0.667 to account for.
Molecular Oxygen:No photosynthetic life, and so no free oxygen in the atmosphere.
Helium: The planet’s M-number is 6, so there will be no significant helium in the atmosphere.
Argon: Alice rolls 3d6 for a total of 9, multiplies that by 0.001 and then 0.7, and rounds the result off to 0.006 for the partial atmospheric mass of argon. She updates her tally of atmospheric mass and still has 0.661 to account for.
Molecular Nitrogen: The last 0.661 of atmospheric mass will be composed of molecular nitrogen and traces of other non-greenhouse gases.
Alice multiplies all of these partial atmospheric masses by the planet’s surface gravity of 0.82, and arranges them in order from largest to smallest:
Molecular Nitrogen: 0.542 atmospheres
Carbon Dioxide: 0.027 atmospheres
Argon: 0.005 atmospheres
As expected, the atmosphere of Arcadia V is completely unbreathable, and in fact the high partial pressure of carbon dioxide would be mildly toxic to any human who made the attempt. Visiting humans will need full respirators.
