Tuesday, 31 May 2016

Why go?

Why aren't we going to space? Where are the fleets of space stations promised in the '50s? Where are the dozens of flights a month the Space Shuttle was designed for? Why has there never been more than 13 people at once in orbit?

In this post, we'll tackle one of the major questions that hard science fiction has to confront, and that is creating a setting with appropriate motivation for going into space.

Motivation: Why leave Earth?
A most expensive view
Space is expensive.
Reaching it burns dollars and rubles. Staying in space costs even more. In a rational world, you spend money to gain utility. When millions and billions are spent putting a payload in space, the utility you expect to gain in return should worth at least as much.

During WWII, V2 rockets were studied for the same basic concept in mind. The motivation was that rockets with extreme range could bypass the enemy's defenses for a much smaller cost than sending hundreds of fighters and bombers to do the same job.
Peacekeeper MIRVs re-entering. They could have been capsules.
In the Cold War, the motivations were clear. Putting a capsule in orbit, and returning it to the ground accurately and safely, was a stand-in for a nuclear warhead reaching a target city unharmed. Every dollar spent on NASA saved a dollar from the DoD.

With the collapse of the Soviet Union, the military motivation for putting people in space has been dampened. Instead, we go to do research or to place commercial satellites in orbit. A small telescope in space can replace a giant telescope on the ground. DirecTV invests 1.8 billion dollars on four satellites, but expects to earn over 50 dollars a month from 20 million viewers.
A cheaper climb

A lot of research has been made into tackling the cost problem directly.
Currently, it costs tens of thousands of dollars to put a single kilogram of payload in orbit. It costs even more for higher orbits, such as geostationary.

The most common approach today is common core launch vehicles. By only building one booster, and using multiples for larger rockets, economies of scale can be achieved. 
The Delta IV Heavy. Notice how the three boosters are identical.
Another approach is recoverable rockets. Today, this is most prominent in SpaceX's designs, with the Falcon 9 being able to land again after a launch. By re-using the majority of the rocket, you save on having to build a new one.
Endless elevator music.
Straddling the line between science fiction and actual research is non-rocket launch. Laser launch, space elevators, launch loops and even orbital rings... They promise to reduce launch costs to only a couple of dollars per kilogram, and many do not require much more than currently available technology. They would cost more than the entire space effort until today though.

External forces

An asteroid is coming to wipe out humanity! Aliens have contacted us, and they're not friendly! The sun is going to blow up!

What's in common with all those events? They're all outside of our control, and all have been used at some point by an SF author to justify why humanity has a thriving space presence.

Please don't do this to your setting.
Sometimes, this justification is executed correctly, as in the case of Seveneves by Neal Stephenson. The Moon blows up, and humanity must go to space to survive, whatever the cost. 

The problem is that using a motivation such as asteroids or aliens runs the risk of the reading losing their suspension of disbelief. If it's asteroids, the obvious solution is a cold, slow robotic vessel with a feeble ion thruster that pushes the rock out of the way over the course of a few decades: hardly exciting. If it's another such natural calamity, then the best course of action is always staying on Earth and building shelters that take maximal advantage of the free water, oxygen, gravity and other such resources humanity evolved to need. If it's aliens... well, you lose a lot of what makes hard science fiction an exceptional genre.

The other problem is not directly related to the setting, but to the actions of characters within. A strong story relied on characters making meaningful decisions. When using external forces, you have the plot drag along the characters instead of the other way around, and this weakens the story. 

That is not to say that external forces should be avoided entirely, only that more care should be taken than when developing an internal motivation. 

The Means without the Motivation

If you present a man with a hammer, he will find ways to use it.

This concept exists in economics as Say's law. In science fiction, it has taken the form of sudden advances in technology giving humanity the means to do something they didn't need to do beforehand. Examples majoritarily include a new means of reaching space and the stars beyond.

The means AND the motivation
A faster-than-light drive that instantly teleports you to another solar system might have near-zero demand for it at the moment of its conception. However, the moment it is produced, people will realize that the cost of using the drive is immeasurably small compared to the potential benefits. Exploration, scientific research, resource exploitation, sheer curiosity and 'why not?' attitudes... the motivation for reaching space will appear as suddenly as the means to access it is provided. 

The same goes for variants on anti-gravity, reactionless and thermodynamics-violating technologies. Sudden, easy and cheap access to space.

Can this work in a realistic science fiction setting? Absolutely!... if applied correctly.

For one, research is no longer the domain of a handful of privately funded mad scientists that can afford to keep their findings hidden from the general public until the final demonstrator is built for a World Fair. Today, research is expensive, long and very public. Even stealth planes are demonstrated proudly, and the greatest potential discoveries of our time are tracked on RSS feeds and news headlines. 

ITER in construction. Not hidden in a basement laboratory.
So, a fantastic new technology won't appear suddenly. The theoretical concept might be surmised from a laboratory accident, but the following billion-dollar research and development will take years.

Secondly, fantastic new technologies don't happen in a vacuum. Internal combustion required oil, jet engines required molybdenum, solar panels required selenium... an author going for plausibility might want to mimic this trend by inventing a special resource that their technology requires...

Unobtanium from Avatar.
A tried and true motivation for going into space is a resource that cannot be obtained on Earth. This can be a substance, or a service, such as a construct that can only be built in micro-gravity. 

MacGuffinite embodies this concept. It is a fictional resource that for the purposes of having humans in space, can only be harvested by engineers and miners in the Asteroid Belt. 

One famous, oft-used example of such a resource is Helium-3. If we put as much thought into it as the authors did, it sounds great. A futuristic element that requires us to set up lunar mining colonies, and it's 1969 all over again.

Helium-3 mining from the movie Moon.
It falls flat if we dig a bit deeper. 
The Moon has 100 times more Helium-3 on its surface than Earth, but extracting it here would still be cost effective. It wouldn't require humans to mine it, only robots tele-operated from Earth with a one second of delay. And it entirely dodges the issue having to invent economically sustainable He-3 fusion in the first place (as opposed to D-T).

A variant on the MacGuffinite concept solves one problem and creates another. Helium from Jupiter! We've heard it. It justifies humans in space because of the 33-53 minutes of communications delay. It would be less expensive to put an engineer nearby than to constantly lose robots because they didn't react to a threat they didn't recognize.

It breaks down, of course, due to the fact that even science fiction authors who put above-average thought into their setting don't understand orbital mechanics and deltaV.

Jupiter mining station by Adrian Mann.
Jupiter has a huge gravity well. This means that a rocket that plunges into a low orbit, scoops gas, then accelerates back to a high orbit will require incredible amounts of deltaV. In other words, that spaceship will be 95% propellant and 5% everything else. That 5% has to carry the engines, reactors, hull and whatever gas you scooped up. Considering that Helium-3 has a concentration of 0.01%, this will never be economical until ridiculously powerful engines are invented.

Spurred on by the requirements of realism to justify a human space presence, and yet unwilling or unable to work out a setting that justifies the exploitation of a real world resource, many give up and turn to a fantastical element. Unobtanium. Magnetic monopoles.  They are so amazing that any cost involved becomes justified. In Avatar, the magical properties of the setting's MacGuffinite spurs humanity to develop an important human presence in another solar system. While solving the issue of motivation, it is subsequently forced to ignore the huge number of secondary issues, requirements and untackled consequences such a demand has. 

Once again, this does not mean that all MacGuffinite is bad. It's just that it should be used as a sort of last resort to achieving the setting you are aiming for. 

The Literal Right Stuff

If you want to write Tough Science Fiction, or create a setting where a reader nods and says 'makes sense!', then you're going to have to put the work in.

An asteroid mining base.
Look at the resources that we currently need and those that we will need.

An example of the first kind is crude oil. The world economy depends it, the price is under the control of an unstable organization, and increasing prices make expensive extraction schemes profitable.

We can look at phosphorus. There's very little of it in the rest of the solar system. If we colonize space, and start growing our own food on the Moon or on Mars, then phosphorus will become an important commodity. Since it would have to be lifted up from Earth with an 11km/s deltaV deficit before it goes anywhere, it will necessarily be valuable. This is the second type of resource.

Your job now is to devise a series of events and happenings, in short, a future history, that ends up with your chosen resource being transported back to Earth from other celestial bodies. Base yourself on what has already happened: the Silk Road, the spice trade, the East India Company. As long as the people and nations in your setting aren't nobler, stupider or crazier than people of the past, then you can't go far wrong. 

A good setting manages to set up the full chain of supply and demand, from extraction and transport through to processing and stock markets. It works out consequences such as worker colonies in outer space, alternative resource streams and the effects of technological innovation.  

A great setting has more than one of the Literal Right Stuff being developed and traded. If you focus only on interplanetary platinum, you'll end up with a bland monopoly with one or two mega-corporations absorbing the costs, and the extreme prices off-setting the cost of automated mining installations suddenly crashing without supervision. That isn't much different from today's mostly automated mines, and they aren't terribly exciting. Instead, you can get a rapidly expanding space presence if you trade terrestrial uranium and phosphorus for interplanetary iridium and nickel. Trade and supranormal profits has driven humanity to settle the corners of the Earth, so there is no reason why the same can't push us to the ends of the Solar System.  

A great setting isn't afraid to show progress either: if the oil lobby is eradicated by off-planet extraction, then electric cars and renewables will develop at their natural rate and eliminate the need for oil all-together.   

Politics and Society

A final motivation for reaching space can exist regardless of any cost/benefit analysis. In many cases, it goes against what a rational person would choose to do.

We chose to go to the moon because otherwise they'd get there first.
Political and military motivation has often been a motivator as powerful as economics in pushing people to explore the edges of their world. It was the principal component behind the Space Race and the funding for the Apollo space program.

However, it is a very weak excuse for placing humans in space.

Wars can ask of humans to go to space, but after the Cold War, it became evident that soldiers are best serve staying on the ground,w hile the vacuum of space remains the domain of robots and spy satellites.

Communities wishing to remove themselves from the rest of society are unlikely to have the funds required to do so. They are better served by moving elsewhere while remaining on Earth. 

In future decades, overpopulation and lack of food might make it feasible to spend money on building rockets instead of expanding arable land. However, this will be very far in the future, so far that it becomes difficult to ignore advances in medical and biological technologies that might occur in the meantime. 

Imagine how much living space we could gain by adding a second storey to each house.

The standard hard science fiction is held to is that which will not insult the reader's intelligence.  Even without any critical intent, they will manage to find a number of flaws in an excellently built world. However, this is still fiction, so a certain number of 'plot necessities' are required to create an interesting setting out of today's mundane space presence.

So, when you decide to answer the question of what motivated humanity to expand into the sky, tackle it from the point of view of a prospective reader. Does your excuse sound plausible? Does humanity react to it as a normal person would? Does it all react the same way, or do different factions have their own plans?

Whichever motivation you decide upon, or combination thereof, the standard worldbuilding rigor is required. Of course, it is equally appropriate to ignore the question completely. Even the most famous authors make mistakes with their worlds, and if you feel that you cannot appropriately handle the matter, it is best to leave it out of your exposition. Alternatively, create a setting where this is a non-issue, such as something millennia into the future


  1. Is phosphorus really much rarer off earth?

    Life's need for phosphorus just suggests that a lunar colony would be mining KREEP for the phosphorus as well as the Rare Earth Elements and the Thorium.

    Jim Baerg

    1. As far as I know, phosphorus is readily present off-world, but on Earth, it is concentrated on the surface by living organisms, and constantly recycled into organic compounds. The largest source is phosphate rocks such as limestone or mudstone, both of which are sedimentary rocks.

      Somewhere like Mars might have just as much Phosphorus as Earth, but it might not be distributed favourably. On Venus, getting anything from the surface is hard. Asteroids can have a lot of one resource and lack another. In the Outer Solar System, it will be desperately needed.

      KREEP is interesting. It can work as a proof that the Moon is of terrestrial origin.

  2. I have been putting some thought into this and wanted to throw out an idea: Zero g manufacturing.

    Currently we know very little about zero g manufacturing other than that a lot of traditional techniques won't work but this is a huge unexplored area.

    What if the key to fusion energy or mass produced carbon nanotubes or something even more exotic was to have at least some of the manufacturing process at low or zero g? In this way there is a strong economic incentive to develop space industry and one you are up there it becomes self-perpetuating.

    1. Sorry, I've been looking around but I cannot find a product that respects the following criteria:

      -High value per mass
      -Higher value than launch and recovery cost
      -Can be made in space much cheaper than on the ground.

      In space, we can cheaply achieve very high grade vacuum and persistent microgravity. Some materials built with layer-by-layer vapor deposition, such as X-ray dielectric mirrors or long carbon nanotubes, would benefit from such an environment. However, they are more easily made on the ground with a good vacuum chamber. Also, there really isn't such a big demand for such products when even the aerospace industry is just switching to aluminium-lithium as an 'advanced' material.

      You can't build an economy on a tiny demand for niche materials that can also be built on the ground!

      No, the biggest customer for space manufacturing is other space industries. You are better off printing pressure hulls in space to be used as habitats for some other industrial venture, than trying to find some unobtanium that can sustain itself on sales to the ground.

      Of course, you can invent some such material for a science fiction industry. Make sure that the process needs human supervision, otherwise our businessmen will just place an automated factory in orbit!

    2. I guess the macguffinite angle is where I am coming from. Some scientist comes up with a way of making a wonder substance that is only needed in small quantities but must be made in microgravity so an orbital factory is built to make it. This kicks off more research into zero g manufacturing and more products and techniques become available. After a few orbital factories are built it will become economic to mine structural metals out of asteroids etc and a more general space industry will develop to support the factories and it becomes self sustaining.

      The initial product is in some way unimportant as long as it is profitable and doesn't require trillions of dollars in initial funding.

      As for supervision, even the most fully automated factories have some people in them - there are so many moving parts that stuff is bound to go wrong!

    3. You could use the following items as McGuffinite:
      -low defect microchips
      -long carbon nanotubes
      -large protein crystal growth for pharmaceutical purposes (http://gizmodo.com/space-grown-crystals-could-help-us-counteract-deadly-ne-1797016449)

      The problem with these high-value, low-output processes is that they need little of any raw materials. They won't provide the push for a large secondary industry to supply them with space-based sources of raw materials, they need so little that you can just fly them up from Earth.

      I think the best approach is to put together multiple McGuffinites so that all their requirements put together justify a push for asteroid or lunar mining.

    4. I was thinking the opposite actually, the classic ones like he3 etc seem like fantasy to me and only really viable in the far future (maybe). I think that you would only need a modest start to kick everything off.

      For example the iss is very expensive because everything has to be brought up on a rocket. If we decided to build 10 of them next year we would seriously consider sourcing much of the material from asteroids instead. From there it makes sense to have propellant depots in orbit and all of this also results in increased traffic and reduced launch costs. From there people will start to find other things to do to take advantage of this (space hotels, research labs, other types of factory etc) and a virtuous circle begins.

      The only thing we need to decide to build 10 iss style factories is a desirable product that need not be very bulky (like microchips, drugs etc). Everything else just flows naturally from there!

    5. Good idea. You might need a cash-laden visionary to pay for the large scale initial attempt at space manufacturing though. Maybe an Elon 2.0 in the 2050s, where the prospect of space-grown anti-aging drugs and high-quality super-processors becomes an interesting investment...

    6. Joe Haldemans space colony series used zero g produced "foam steel" as it's excuse. It worked better than e.g. drugs because it was a bulk commodity. Which meant diverting asteroids to earth orbit and that it didn't make sense to try alternative manufacturing techniques on earth.

    7. Metal foams are a real thing!: https://en.wikipedia.org/wiki/Metal_foam
      However, we have learnt how to produce them on Earth rather than requiring the help of microgravity.

    8. Metal Foams are pretty awesome especially CMF. I would love to see a post on here about metal foam applications in starships, I.E. in armor etc.

  3. One possible base for the bulk cargo of an interplanetary economy is CHNOPS - carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur, those six elements which make up the bulk of all known life. Taking Terra, and the three common "early" colonies (Luna, Mars and Venus), you can see that besides Terra, each lacks at least one.

    Luna has H and O (from water ice) as well as P from KREEP and S from Troilite, an iron sulfide mineral that makes up about 1% of the lunar crust and may be concentrated in veins, but is quite depleted in C and N.

    Mars has C, O and H in abundance, and is apparently also somewhat rich in S, but lacks P and N.

    Venus's atmosphere is an abundant source of C, O, N and S, but P and H are likely quite scarce. Also, Venus has the disadvantage of a gravity well that is almost as deep as Terra's.

    So, the interplanetary trade streams I can see is phosphorus being traded from the lunar KREEP mines to both Venus and Mars, while Venus exports nitrogen to Mars and Luna, Mars and Venus export carbon to Luna, Luna and Mars export water (or just pure hydrogen) to Venus, and all export their respective resources to in-construction orbital habitats.

    This already sets up conflict potentials - as the only cheap source (for not paying the high gravity tax of launching off Terra) for phosphorus would be the lunar KREEP mines, and this will be a resource even more essential than oil is to our current society, I could see the different lunar KREEP mines forming a cartel similar to OPEC - it could even be called OPEC, Organisation of Phosphorus-Exporting Colonies, if you want to hang a lampshade on it. This could then drive up prices, and KREEP miner strikes would be a major concern, as well as there would be an option for a disruption (and, if sufficiently powerful, OPEC opposition, even military, to that disruption) of the phosphorus trade by asteroid mining.

    1. I agree with the element-scarcity base for trade between planets, and it is one of the main topics of the 'How to Live on Other Planets' series. However, interplanetary trade cannot happen if you have nothing off-planet. In other words, you must solve the critical barrier between our current ground-hugging economy and a future with significant space presence.

      It is that problem specifically that this blog post addresses.

  4. You failed to mention religious pilgrimage. The Puritans in colonial America and the Mormons crossing the plains are examples of groups engaging in expensive, difficult, and deadly (many Mormons died in the crossing) endeavors to escape persecution and find a promised land.

    If the group feels (either real or perceived) that there is no place on earth where they can find their promised land, they'll head into space.

    1. The idea that a group can be powerful enough to command the resources for space colonisation but not enough to secure itself on earth isn't really one that works. A lot of mormons pushed hand carts across the us, and the Mayflower was the equivalent of a tramp steamer.

  5. I didn't get half of what you have written(because of my lack of knowledge of hard Science.)

    I wanted to write a Sci Fi story about a group of young Astronauts going to other Solar system for fuel and other precious elements.

    Now I think my motivations are weak.
    I knewed that most of those things can be found kn our solar system and there was no need for our heros to go to unknown world but for exploration and Adventure, I thought it was a god idea.

    Can you help me please and can point out any real element which is hard to find in our solar system?
    I will search about it too.

    1. Check out my writings on Interstellar Trade: http://toughsf.blogspot.com/2017/03/interstellar-trade-is-possible.html

      It is possible to go to another solar system in search for rare resources like Platinum Group Metals, but it will take many decades before the first product arrives at Earth. If you go to another star system, it is because you want to set up a new civilization over there.

      The motivation for human settlers will not be material or economic, but ideological. For example, someone might want to create a new way of living in a place that no other people can reach.

    2. No. That only works if the technology required for transportation and colonisation was already paid for by some other activity which had the support of the group controlling the economy. The Mayflower was possible because millennia of effort has gone into refining sea transportation. The idea that an isolationist group is going to have the enormous resources required to develop space colony tech isnt realistic - it isn't even realistic that they'd take the gamble of investing them that way instead of e.g. hiring lobbyists or establishing an enclave in a bribed third world country. Or committing terrorism.