Worldbuilding & Astonomy: What’s the second biggest thing in the solar system? And you think you’re going to mine a gas giant?

So, yar, here’s a question for you:

What is the second largest physical object in the solar system?  (No, not made up stuff like “The orbit of that planet that lost its charter!” – the orbit isn’t a physical object, it’s what we use to describe a particular path, but I’m talkin’ something that exists all at once largest.)


Ah, yes, I see your hand up there, Mr. The Science Geek.  And I’d let you answer, but I gotta finish this blog post and I can’t quote you if I don’t actually have a quote. But it’s what you’d answer if you were here. Which you’re not. You’re in Great Britain, or technically, England, which brings me to all that third grade stuff of subsets, sets, and so on.  England is a subset of Great Britain. But everyone uses ’em interchangeably anyway.


The answer is the magnetosphere of Jupiter.

BOOM! Maybe you were thinking the answer was “The Sun!” And that’s not correct either. Technically, the largest object is the Heliosphere, which is the region of space dominated by the sun, or its particles. That extends beyond the imaginary orbit of pluto you were trying to stick in up there.  I saw you guys.  Just admit it.

The magnetosphere is this amazing HUGE HUGE HUGE “cavity created in the solar wind by the planet’s magnetic field,” says the anonymous people at wikipedia, who never lie or twist things to their own happy little wikirelativistic viewpoints. Anyway, here’s the conclusion of that fine article:

In 2003, NASA conducted a conceptual study called “Human Outer Planets Exploration” (HOPE) regarding the future human exploration of the outer solar system. The possibility was mooted of building a surface base on Callisto, because of the low radiation levels at the moon’s distance from Jupiter and its geological stability. Callisto is the only one of Jupiter’s Galilean satellites for which human exploration is feasible. The levels of ionizing radiation on Io, Europa and Ganymede are inimical to human life, and adequate protective measures have yet to be devised.

What a nice way of saying YOU WOULD BE RADIATED TO DEATH IN A FEW MINUTES WITHOUT A COUPLE TONS OF LEAD TO PROTECT YOU.  Really. Pleasant. “Inimical to human life.” Written by a scientist. Where’s the passion? Where’s the love? Say, “you’ll be KILLED IF YOU LAND HERE!”  See how much better that pops?

Ah, so you’re writing a book, like you do.  Lots of those being written around here. And lo and behold, you decide “I’ll just have everyone refuel at the magic HE3 depository in the local gas giant. Cause, well, cloud scoops are easy. Go cloud-scoops!”

See, there’s a little tiny problem with that. Unless they’re robotic cloud scoops, the chances of you getting close to a gas giant are pretty minuscule. (Yes, I spelled it right. No little “i” for that word.) BUT WAIT! Just because Jupiter has this huge nasty solar plasma die-all-life thing going on doesn’t mean all gas giants do. Bad ol’ Jupiter is different. It’s got its own issues. What about that nice boy living next door, Saturn?

I’m glad you asked. Saturn has the same durned problem.  Big ol’ magnetosphere, which must be an interesting interaction when Jupiter’s Magnetosphere interacts with Saturn’s Magnetosphere.  “You got your chocolate in my peanut butter,” they might say, if planets talked and stuff. Which they don’t, mostly, unless you’re writing moonbeam sci-fi and you’re a big proponent of medicinal marijuana, for your hypochondriaca melencholia.  Jupiter’s magnetosphere extends into the orbit of poor ol’ Saturn.  I haven’t seen any writing on the subject of that interaction, though it might be because the two planets line up every 20.47 years or so.

[Quick! Algebra problem. Planet J orbits the sun every 12 years. Planet S orbits the sun every 30 years. How often will the planets line up? Show your work. I think it’s… well, 12/30 = .4, so Saturn travels 40% of its complete orbit in the time it takes Jupiter to go once around. So Jupiter has to catch up, and that means it has to travel an additional 40% of its orbit, which is 12*.4 = 4.8. It would take Jupiter 16.8 years to catch up with Saturn each time.  But… Saturn is still moving, so it’s actually higher. Math is not Mongo’s strong suite, yanno? I found this equation. Mongo fail. The answer is 20.47 years. I blame Kepler for this misunderstanding.]

Magnetosphere of Jupiter was discovered in 1973. So they had, at the most, two opportunities to study this complex interaction, and considering that the measurements of these two things come from spacecraft flying by, it’s impossible for anyone to know this.

We have two gas giants, both of which exhibit the same sort of affect on the sun’s plasma streaming by. Perhaps your gas giant is different, and managed to escape all those pesky magnetic fields generated by the the enormous amount of metallic hydrogen in the center.

Or maybe, in your universe, someone solves the blamed problem by inventing a miracle armor.  I wouldn’t put it past y’all to do that.

Go ahead, comment. It won’t kill you.  And, um, it’s not because I’m desperate. Because I’m not. I’m NOT! Just comment. If you comment, I’ll be your best friend!  C’mon. I’ll give you a cookie! Yeah, I love the “Don’t Let the Pigeon Drive the Bus” books, too.

Worldbuilding – entropy and raising the stakes: Stuff Breaks

I read a fair bit of sci-fi. Most of the time, the good guys do their thing and fight and there’s aliens and stuff and it’s all copacetic.

Considering that most of the cool wonder gadgets in the bright new future all work intuitively or with instant mind instruction, and there’s no moving parts and nothing ever breaks…

You people aren’t living in the world I live in. Consider the coolest gadgets you own.  Like… your computer/tablet/whatever that thing is called. It’s got storage of some kind. RAM, a hard drive, a solid state drive, or some quantum technology that the government has secretly suborned and killed all the creators so they can build cool stuff in the Nevada desert.  What’s the lifespan of that gadget?

And when it does go toes up, when will that event happen?

Why, it will happen when you need it the most.  People don’t have heart attacks at the hospital, they have them in a car stuck in a snowstorm during a blackout where solar flares are scrambling cell phone signals.

Same deal with your electronics.  Those whiz-bang cool gadgetry things you stuff into your pages… If it’s built by humans, ones interested in selling more whiz-bang cool gadgetry things, it’s going to break.

I’ve been thinking about my poor marines I’ve marooned on a perfectly good inhabited planet. They’ve got the best combat suits in the universe. Er, not really. They’re going to discover that the stuff they have is 50 year old technology and that the new Mark V model is streets ahead of what they’ve got.  And 50 year old technology breaks. A lot. Why? There’s a supply chain that has a lot of corrupt people in it who are taking value out every step of the way.

I read stories where the protagonists have advanced equipment and manage to keep it running in fairly barbaric conditions for long periods of time. I’m giving it the hairy eyeball by the time I’ve finished, because stuff doesn’t just keep running. If it does, you’re truly blessed because it does not just keep running.

Use this to raise the stakes. We might be able to take that hill with five tanks, but one’s got a bad reverse so he’s going back to the depot and we only have four. And we suspect the fifth tank crew of cowardice and making it all up. Equipment breaks. It wears out. It needs frequent maintenance and replacement.  Filters must be cleaned and replaced.

Guns, if not maintained, break. Some break more often than others due to design.  Troops know the problems with weapons and will sometimes try to fix the problem – for instance, the marine corps typically has had their armorers take weapon variants and create work-arounds for problems with the weapons. Weapons are produced which jam, blow up, don’t work in the mud, the rain, the snow, and any other conceivable situation.

Parts on spacecraft break We see this in the first Star Wars movie, where for some reason we keep going back to Tatoine. Why George why? The ship needs some part and without it, they go nowhere, so there’s more plot development there due to Stuff Breaks.

The next time you need to raise the stakes and make your characters just a little more miserable, have their stuff break. It’ll create all sorts of convenient conflict. You didn’t want them to have it easy, did you?

Go ahead, comment. It won’t kill you.  And, um, it’s not because I’m desperate. Because I’m not. I’m NOT! Just comment. If you comment, I’ll be your best friend!  C’mon. I’ll give you a cookie! Yeah, I love the “Don’t Let the Pigeon Drive the Bus” books, too.

Military ranks – sci-fi

I’ve seen a fair few numbers of military sci-fi novels that do interesting things with ranks. The modern ranking system has some meat to it, in that we see certain positions going back centuries and millenia.  Others, not so much.

There’s two approaches I see: 1) Historical, based on a present day military ranking system of a particular country; 2) Non-historical, either because the author doesn’t understand military ranks or they are deliberately changing it.

Historical Ranks

The advantage of using a system based on historical systems is that there is a lot of knowledge out there available to interpret and understand the ranks. Some authors may draw from their own knowledge and experience in the military.  There are nuances for different countries, and even the different services may have ranking systems that are not strictly using the same rank names for the same ranks.

Witness, for instance, the navies of the future.  If you’re using the United States navy, you have some classifications that might not sound right applied to space navy: Seaman, for instance.

You also have rank names and titles based on hundreds of years of traditions that are in turn descended from word origins that may or may not make sense. Lieutenant, which is Leftenant in the UK, is from the French.  The position is a junior officer in the US Army and USMC, but it’s a mid-level position in the US Navy.

While I was reading the Honor Harrington series, I thought it was fascinating that David Weber carefully brought forward the ranks and roles from the current UK modern navy, and even utilized the terminology.  It was a sort of look of “what would the English navy look like in space”?

If you’re going to use historical ranks, try to understand them enough to know what they do. Which ranks typically lead which sized forces?

Don’t mix up the force compositions. If you’re talking about a fireteam, that is not the same as a squad (it’s usually a sub-element of squad), or platoon, or company, etc. Those are terms of art and they have meanings that resonate with military guys.  They may differ from nationality to nationality.

In the Warstrider series, the ranks and force composition names are Japanese, reflecting the culture of those worlds.  I’ve seen Chinese ranks used as well. The future of space isn’t always ‘MURICA!, though it feels like it most of the time in the books I read.

Making up a new rank system

I believe that if you’re going to create a new ranking system, while it’s comfortable to use historical rank names, it’s going to look like you botched your research. When you say “this guy is an optio and he’s in charge of 100 men” that makes some readers’ heads hurt. We’re thinking, “no, you mean centurio, and it’s only 88 guys.”  Make up new ranks and rank structures with non-historical names, and you avoid this problem.  We readers have all this baggage about what we think it’s supposed to be, and it bothers us, a lot, when you do something that breaks the mold of what we think that means.  A sergeant is an non-commissioned officer (which is another funny term- if you don’t have commissioned officers, can you have a NCO? Or does it want another title?) so he shouldn’t be doing officery stuff, and vice versa.

Or make it clear that you’ve departed from the wonky historical ranks. You could have private 7th class as your lowest rank, and then after that, sergeants first through fifth class, and so on. Those people who don’t know what a first sergeant is or a staff sergeant or a master sergeant aren’t going to care, as long as they can get your system and understand the inherent rank status of each character.  Higher or lower?

Force Composition – Who leads what?

One thing you should consider is the makeup of the forces each person commands. The US has been experimenting with the ideal number of people under command of a person for over sixty years, and they think it’s four person teams, typically. This doesn’t mean you’re wedded to that fact, but you should consider force composition before blithely making up numbers. This is one of those areas where it won’t ring true if you say one guy is commanding, say, 48 people with no other NCOs or officers.  That’s a platoon, by the way, and there’s usually a ton of people to make everything happen.  For instance, you may have:
Platoon leader – 2nd or 1st Lt. (48 people under)
Platoon Sergeant – Sgt. or Staff Sgt. (directly trains the 4 SLs)
4 Squad leaders – Corporals or sergeants (12 or 8 people under)
3 or 2 fireteam leaders in a squad – specialists or lance corporals or corporals

And then there’s the idea of battle-buddies, which is that you have a guy to look after you and you look after him.  The Air Force calls that a wingman. We know from Top Gun that you never, ever leave your wingman.

Even in the four man fireteam, there is rank hierarchy due to position.  Thus, the fireteam leader is carrying a rifle with a grenade launcher, his battle buddy might be the least experienced guy who gets just a rifle, and then there’s a MG guy and his battle buddy humps ammo for him.  It’s VERY clear who is next in line for command of the element, because when the guy in command is killed or wounded, the next person has to take over.

The end result of that whole mass is that each person doesn’t command more than 4 people. Wait, Pontius, you say, the Lt. commands 48 people. No, he doesn’t. He tells their NCOs what he wants to have happen and they carry it out. So he’ll talk to the plsgt or the SLs and tell them that he wants them to move to a ridgeline using bounding overwatch and then provide fire suppression on position x.  The squad leader makes decisions and issues orders to the fireteams, and they execute the orders.  The Lt. does not give orders to individual soldiers at the end of the line; he goes through intermediaries and lets them use their training to carry out the orders using their best understanding of tactics, techniques, and procedures.

Higher Ranks

The higher ranks are more esoteric; at a certain point, maybe at battalion level or higher, the officers aren’t in combat, aren’t in the field, necessarily. They’re directing things, again with a low number of officers directly reporting to them so they can keep the information flow going.

Think of it like trying to play four games of Risk simultaneously.  The information flow is going to be rocky; you might be getting slammed on one board while you have a great position on another, but your attention is limited and you can only focus on one thing at a time.  The joy of computer systems is that it can sometimes prioritize things and organize things for better review, and your sci-fi universe can reflect that.

That’s it, in a nutshell.

Edit-  To help you out, current US Military ranks are found here:

Go ahead, comment. It won’t kill you.  And, um, it’s not because I’m desperate. Because I’m not. I’m NOT! Just comment. If you comment, I’ll be your best friend!  C’mon. I’ll give you a cookie! Yeah, I love the “Don’t Let the Pigeon Drive the Bus” books, too.


Science Fiction settings – Worldbuilding – Economics of your solar system

This ties into my other post,  Science Fiction settings – building the universe, solar system, planet

Pyramid of Needs

One thing you rarely see, or perhaps you may only see a little bit of it, is the economics of a star system. Human settlements do not thrive in places where the economics do not support it.  Human habitations require air, food, water, shelter, and room to exercise.

After that, they branch out to things that feed the mind and soul. But if one of the basics is missing, you can bet that’s the one that will be bothering most of the characters in your story.

Aside from that, your characters need to live in a universe that makes sense on paper to you. You may decide not to include that information in your book, but it’s useful appendix information and it ensures your world makes logical sense.

Worlds can provide three raw materials: Food crops, non-food crops, and minerals. Included in the food crops are domestic and wild animals.  It makes sense to locate a factory or processing unit close to the source for whatever it is you’re doing. Therefore, if you are refining ore, you put the refinery next to the mine.

Space won’t produce the food crops and non-food crops as much, because everything you do to make those things happen requires expenditure of labor and materials to create an environment that will survive and thrive in space. That isn’t to say you can’t do that, but if you have other options for agriculture such as a planet, you do that.

Space also provides minerals on planets, and perhaps if you have a gas giant, there may be some fuels minable from that gas giant.  The most recently proposed these days is HE3, supposedly a good little molecule for cold fusion energy.

However, in space and on planets, you can create factories and technology.  There are many advantages to creating a factory in space, mostly because micro-gravity makes economy of scale easier in some senses. (Pouring hot metal into molds is one thing I can think of that has problems in micro-gravity, but maybe there’s a way to combat that.)

Factories manufacture things. Whether robotics or humans or a hybrid are used, factories manufacture things for amusement or for work. The things may be metal, which must be worked through molding, processing, drilling, welding, brazing, and cutting.  While robots are efficient, they sometimes break when parts wear out and there’s a nice human job you probably (can’t) replace.

Once things are manufactured, you either need to move them into orbit out of a gravity well, or you manufactured them in microgravity and can congratulate yourself on not getting mired in additional expenses to get your finished widgets off the planet.  Instead, you can serenely float them over to the freighter ship.


Humans are very good at producing adequate information.  [Irony alert: Some of it is fiction.] There is also considered value in art which might not have any intrinsic value otherwise.  Art fills the spectrum from written, spoken, acting, painting, drawing, sculpting, singing, making music, and so on.  Something that doesn’t produce a valuable commodity in the sense of meeting the triangle of needs (food, shelter, etc.) may be valuable due to its impact on the human soul/brain. What are sports other than games we enjoy for the entertainment?

The arts usually spring up anywhere humans are, and organized professional arts stem from the presence of upper strata high economic status people who have the money to invest in such things.

Communicating that information from place to place is vital. How do solar systems communicate? Is there some sort of FTL system in place, or are there wormgates and black holes where buoys go back and forth, or do ships carry data packages when they travel? How about money? How do you handle that when someone is traveling from system to system, and you do not have instantaneous ability to track money being transferred?


The technology of your ships may limit their size, but consider that stuff in space doesn’t need to be streamlined, or pretty, or even attractive to the humans working in it. It could have zero outside aesthetic. It just has to work. The limitations on size you get from terrestrial limitations on ocean-going freighters or trains is eliminated in space.  Potentially, you could tow thousands of containers behind your ship, as long a you have a good way to stop all that forward inertia. In many ways, it’s like a train of containers, if you think of it. Once stuff is moving in space, it continues to move until it is stopped by something else, or it enters the gravitational pull of a sun, planet, or some other object.  Ultimately, it’s the cost of obtaining fuel that will affect shipping prices, and the shipping prices affect how much of what gets shipped where.

Shipping can be done by small shipping companies such as sole proprietors, or by consortiums, or large corporations, or governments. In recent human experience, the trend is toward large corporations buying up smaller operators and creating monopolies or something fairly close.


Investors in planetary colonization want to see a return on their investment. That means that they don’t occupy a planet for the pure pleasure of being there.  Here’s the sorts of things that would appear as planetary colonies:

Science outposts/stations – study of the planet, wildlife, geology, plants.
Military outposts


One major factor for a military is who holds the command, which is usually dictated by who holds the purse strings.  With that in mind, your military is constrained from growing bigger by how much money it costs to operate. If your military is too large and takes too much money, it undermines your economy and will cause your economy to fail. However, there is a tipping point and your military can actually prop up your economy if it’s big enough.

Example: In the 1950s, the Honduras and Nicaragua had a small air war. The economies of the two respective countries allowed them to purchase 15 year old fighter planes from the United States or other countries. One country had a dozen F4U Corsairs, and the other country had a dozen P51 Mustangs.  The resulting air battle is one of the only known situations where the two planes were pitted against each other in combat.  The economy of the two countries did not permit them to have jets or modern aircraft. They couldn’t afford it.

So, consider the economics of the Star Wars universe.  What’s the line item cost of a Death Star?  Who builds such a thing?  Does it make sense? Not very much. What do you need a Death Star for? The opposition barely has a few starships.  It makes for a good tale, but doesn’t stay propped up if you consider the sheer amount of money such a thing would require.

Social Services

Depending on the sort of government you employ, the economics of a system will include a fair bit of charity.  Charity is when a person or government gives goods or services to someone in exchange for a discounted rate or no payment at all.  Wherever humanity exists, there also exists some sort of charity.

Interest rates and inflation

This is more detailed than I have time for in a quick overview, but there are many economic theories floating around, and you can get the gist of them by doing a search on google.  You can also find some theories surrounding some economic situations that may contribute good story ideas.

For instance, a large country has a surplus of grain, so they donate that grain to a starving country. However, the starving countries’ farmers are undercut by the free grain from the large country and they thus go out of business. Later, the large country stops sending their grain surplus and the starving country has nowhere else to go.

(I believe this describes the United States’ relations with some African countries, which is simplified in this example, but you can certainly see the conflict this would introduce.)

Strange Quirks of the Rich

If you’re rich, you understand this. (And you should donate sums of money to me because you’ve obviously found this post useful, or you wouldn’t have read all the way through. Just sayin’. Send me emails.)  People who are bloviated rich do absurd and stupid things for which the rest of the universe has no answer.  It’s like they wake up one day and say, “I have a zillion bucks. I think I’ll go do something wasteful with it and make everyone scratch their heads.”  And then they do.  This isn’t carte blanche for you to start writing that into your stories, it’s saying that you can sometimes put something in there which has no explanation other than, “Bill Gates wanted that to happen.” It’s sort of like all the weird stuff you encounter in a James Bond story… it’s done purely because it’s exotic, not because it’s sensible.