What Exponential Space Capabilities Can Look Like

People know that computers became a multi-trillion dollar industry because it rode the exponential growth in power of Moore’s Law. Aviation also experienced decades of exponential growth and Space has had ten years of exponential growth and is looking at 40 years of exponential growth.

Air passenger travel had decades of exponential growth in passengers.

There were 6,000 airline passengers in the United States recorded in 1926. This grew to approximately 173,000 in 1929 about one million in 1936. Air passenger traffic grew faster in the United States than anywhere else in the world, largely due to superior aircraft and operations methods.

The Boeing 747 was introduced in 1969. In 1974, there were 400 million global air passengers. There were 4.5 billion air passengers in 2019.
In 50 years from 1926-1976, air passenger traffic grew about 100,000 times.
In 43 years from 1976-2019, air passenger traffic grew another 10 times.

Aviation Went Exponential for Fifty Years and So Can Space Transportation

SpaceX is making reusable rockets that are lower cost than passenger airplanes. Passenger airplanes cost about $50 million to $350 million. SpaceX is building the Falcon 9 for about $40 million and the Falcon Heavy for about $80 million. The fully reusable Super Heavy Starship will start at about $200 million and then drop to about $30 million. The upper stage Starship will drop to about $5 million when about 300 are produced every year. Airbus and Boeing were each able to deliver about 1000 passenger jets each year.

The SpaceX Super Heavy Starship will be able to launch 100 tons into orbit in a fully reusable basis, but Elon plans a larger version that will be 4 to 8 times bigger. Elon tweeted that Starship Version 2.0 will be 18 meters in diameter instead of 9 meters. This would mean the area of the cross-section would be 4 times higher. If the height was also doubled then it would have 8 times the volume. The engines would likely be upgraded for the Ultra Heavy Starship 2.0. This means the next rocket might be able to launch over 1000 tons per launch. An ultra-heavy Starship could be mass-produced at a price about $150-250 million.

A 747 had a maximum payload of 130-140 tons. A B52 has 31.5 tons of payload capacity.

Reusable rockets will have ten to thirty times the speed of passenger jets and ten times the capacity if the purchase prices are matched.

Ten Thousand Ultra Heavy Starships to Mars

The world currently has 25,000 passenger planes and this was projected to triple by about 2050. If reusable rockets were to replace passenger planes for long-distance travel then there could reasonably be a market for twenty thousand Starship variants.

If ten thousand ultra-heavies were launched to the Moon and to Mars, then they could bring ten million tons of equipment, habitats, factories and material to each location.

Lighter weight steel construction of high-rise buildings has been achieved in China. Broad Group has built many twenty-story and even a fifty-seven-story building. 270,000 tons of steel would be needed for an older design 200 story Sky-City building. This had an average of 6000 square meters per floor or about 65000 square feet (1.5 acres per floor).

Hollow cylinders of steel have been developed by Broad Group in China. This increases the strength but reduces the weight of construction by 30-60% for buildings, ships, planes and cars. This could lower the requirement for steel down to about 100,000 tons of steel for a large 200 story building. This would have 300 acres of floor space which is almost half a square mile.

Ten million tons of capacity is enough for 2 million people, buildings, supplies, factories and equipment. There will be several gigawatts of solar power and batteries.

It would be easy to create cement production on Mars and the moon. There is water on Mars and the moon. There is literally a frozen ocean on Mars and there is a small frozen lake on the moon.

SOURCES- Elon Musk Twitter, Tovera twitter, Broad Group
Written By Brian Wang, Nextbigfuture.com

82 thoughts on “What Exponential Space Capabilities Can Look Like”

  1. Maybe space will be where the new Puritans and Quakers will go so they can practice their religion in peace. There is a trillion comets out there, enough for everyone.

  2. I could see tourism for a few thousand people. Maybe $1 million a pop. That would be a few billion a year. I think moon mining and maybe space manufacturing of products that need an high vacuum and/or zero gravity like special alloys, large crystal ingots, purification of proteins. But it will take decades for all of this to develop.

  3. I worked in the structures engineering group for the Boeing 737NG commercial aircraft models. The cost/lb-saved metric for selecting materials and processes used on those aircraft was $300/lb. If the cost of using a material or process was less than $300 for each pound of weight saved, then it was used. That’s how important aircraft weight is to the economics of the commercial air travel industry.

  4. One factor affecting the aircraft pricing may have something to do with the number of employees. Boeing:160000 and Airbus:136000. SpaceX:8000

  5. There isn’t much nitrogen on the Moon to make 14C, in particular. But yes, cosmic rays will make showers of secondary neutrons etc.

    Still, most of the radioactive products are short-lived, at least based on my own analysis of which are most likely. And most of those decay in the beta mode (so does 14C). There are a few exceptions, but they should only contribute a small fraction of the radioactivity. And AFAIK, generally speaking, the longer the half-life, the weaker the radioactivity. That said, the empirical reality may be quite different from my theoretical expectations.

    One other factor to consider is radiation flux. That should drop as the square of the distance from the source, and the distances here are literally astronomical (but OTOH it adds up from multiple sources). So I expect the flux is nowhere near nuclear plant core levels, for example. And then radioactivation should only be a fraction of that.

    edit: from https://en.wikipedia.org/wiki/Orders_of_magnitude_(radiation) :
    Unshielded in interplanetary space: ~0.1 mSv/hr (per human surface area, I guess);
    Level reported during Fukushima I nuclear accidents, in immediate vicinity of reactor: 1000 mSv/hr.
    Estimated dose rate for the inner wall in ITER: 70,000,000,000 mSv/hr

    So yeah, orders of magnitude lower flux.

  6. Thanks for turning my qualitative argument into a quantitative one. Volume increases for a given energy at-launch fuel load. Semi-pressurized cryogenics also prefers oval-to-round cross section tankage. Supercooling on loading might allow for 35,000 foot ambient pressure zero-PSI differential, in-tank to atmosphere.  Insulation needs to be pretty robust, having to be filled and basically emptied multiple times a day.  Thermal cycling, perhaps could be the Achilles Heel of using cryo-CH₄.  You know, cracks, fissures and leaks.

  7. Hmmm… yah. I guess.  

    ¹⁴C comes from a combination of high energy cosmic ray irradiation of
    ¹⁴N + ¹n → ¹⁴C

    Something like 98% of all terrestrial ¹⁴C comes by this route.  Not insignificant quantities, either. The reason cosmic rays ‘work’ is that their initial collision produces a daughter-particle shower of decreasing energy each generation. The number of produced neutrons can be quite high — thousands to hundreds of thousands — per UHECR.

    Thing is, similar daughter-produce chains when cosmic rays hit anything. Might be more compact because of the density of the material being pierced.  Same basic dynamics.  So, depending on the composition of the regolith, quite a few neutrons possible.  

    Another thing is, that once we set aside the 95% of least-likely-to-be-affected isotopes, we’re still left with 5%, some of which are decidedly less well behaved with regards to isotopic mutation and half-life. ¹⁴C HL is 5700 years. 

    Sure — your argument is well made. 
    So’s mine. I don’t think they’re in conflict. 
    There WILL be radiation. Transmutation. Isotopes.  Halflives.

    ⋅-⋅-⋅ Just saying, ⋅-⋅-⋅
    ⋅-=≡ GoatGuy ✓ ≡=-⋅

  8. The volumetric energy density of jet fuel is only 1.6 times that of LNG (35 MJ/L vs 22). So the tank volume can be about the same if you’re ok with ~2/3 the range. And that may be acceptable if the cost savings are big enough.

    You’d need some padding for the insulation, but for the same energy content, LNG is lighter (19 g/MJ vs 23 for jet fuel), so the efficiency gains could offset the padding.

  9. There are a few caveats to that:

    1. Almost all of space radiation is EM and protons. Some electrons, much fewer heavier nuclei. Practically no neutrons. A large fraction of the reactions would likely be scattering without radioactivation. Only a fraction of the reactions would cause radioactivation, by: A) knocking out some neutrons, which would produce an unstable daughter nucleus and some secondary neutrons, and B) capturing of those secondary neutrons elsewhere.

    2. The 3 most-common elements in Lunar soil: oxygen, silicon, and iron, have two stable isotopes above their most common isotope. So it would take at least three neutrons to activate them. So does magnesium, the 6th most common in Lunar soil. Calcium, the 4th most common element in Lunar soil, is more complex: its most common isotope, 40Ca is observationally stable; the next one decays with a half-life of 100000 years via electron capture (emitting an auger electron or an xray); then it has 3 more stable isotopes, one radioactive isotope, and then another observationally stable one.

    3. Most of the isotopes just above and just below those stable ones – i.e. those that can most easily be produced by either capturing or knocking out a few neutrons – decay pretty quickly to stable isotopes. Within seconds to days.

    So actual radioactivation should be rather limited. And then:

    4. Most of those decays are beta decays (electron or positron), which are fairly easy to shield against. So it’s pretty much a non-issue.

  10. Rocket+payload mass would probably have to scale roughly with cross-sectional area – but volume could scale faster if all you care about is having more room, e.g. for passengers on a long trip to Mars.

    Though actually I see little reason to make a rocket bigger than Starship. If you want something bigger in space, e.g. for long voyages, put it together in space.

    For that matter, if SpaceX could make the engine+fueltank portion of Starship drop off the cargo/crew ‘top’ of Starship in orbit before returning, they could quite rapidly accumulate lots of valuable ‘enclosed volume’ in space – for use as fuel depots, space stations, Mars transit ships, larger but conventional earth-re-entry crew capsules, habs to be landed on the moon or Mars (using much smaller engines), etc.

    One problem with that might be decreased re-entry drag: Starship ‘bottom’ might be too heavy to aerobrake sufficiently without the ‘top’???

    OTOH it’d be somewhat better balanced during aerobraking – smaller/lighter fins at the bottom. Less total mass being landed means less fuel for landing, so more fuel for de-orbit, giving a lower re-entry velocity.

  11. Yes, so long as your magic wand is well charged up and properly incanted (to solve the world-wide-logistics-problem of having liquid methane depots at say 50% of the world’s largest participating airports), then the modifications to wings and so on aren’t all that bad. Airliners might look more like 3-bodied oddities, to account for the cryogenics and out-wing cryo tanks.  But they wouldn’t need to duff liquid oxygen!

    As I see it, this is exactly the same ‘gotcha’ that will negatively impact the roll out of all-electric planes too. How to get the various key airports to ‘hub up’ and invest, or allow the e-planes battery-pack swaps, and have the attending personnel.  

    Same problem. 

    Other than that, Mrs Lincoln, how did you enjoy the opera?

    ⋅-⋅-⋅ Just saying, ⋅-⋅-⋅
    ⋅-=≡ GoatGuy ✓ ≡=-⋅

  12. They’re all awful – expecially the ones with anything to do with the Gummint. I have to get at least an Astronomical Unit away – the Moon is far too close, you can still see them !

  13. Airliners could run at a profit (sometimes) because their fuel is tax free – they pay nothing for their environmental impact. If avgas was taxed at US road fuel rates, let alone European, they’d all be bankrupt straight away. They usually have to line up for government handouts every few years, anyway.

  14. Well for a PhD in Compliance studies we just refer to males as “Proven, suspected and probable future rapists” and collect our floppy hats for the award ceremony.

  15. Come up with a term that those with a diploma in Compliance Studies can utter to demonstrate their More Compliant Than Thou Awareness, and not only may you be in line for a PhD in Compliance Studies, describing the Oppression of the term “coed”, you may find yourself the founder of an entire school of Compliance. Good luck and may the Gods of Wikipedia smile upon your cited works.

  16. A thought just struck me: Can airliners run on liquid methane?
    Has insulation been developed to the point where we can run cold, wet wings?
    Because, as said, super cheap.

  17. Cool. We’ll start up the Brian Pat’n Goat Space Bunny company. Nothing but the finest rivets and space bunny waitresses.  To mop up the puke and loose bowels. And spritz around the narcotic air freshener.  

    ⋅-⋅-⋅ Just saying, ⋅-⋅-⋅
    ⋅-=≡ GoatGuy ✓ ≡=-⋅

  18. One think I don’t know about your American slang.
    If “coed” is short for co-education, ie. males and females attending the same school, then surely both the males and females are both coeds?
    Indeed, as males are the minority, surely they are the ones worthy of a special term?

  19. I suspect that a real answer would start with the wing. A modern airliner wing is a complex system of multiple moving parts.
    The costs of an airliner, from what little I’ve gleaned from my aircraft designing friends, are

    — The engines. But rockets have multiple, big, complex, engines that need great fatigue life while subject to horrible thermal stresses too, so no real advantage there.

    — The avionics. But rockets have complex avionics too. And I suspect that if a rocket is used as an airliner it will end up using the same level of mandatory radar, landing, takeoff, navigation, crash avoidance, as well as flying avionics as an airliner.

    — The wings. Rockets don’t have these as such. It does have guidance fins, but not the big, complex, variable geometry things that modern aircraft have. (Variable geometry such as flaps, not swing wings.)

    — A tube and stuff to put the payload, seats and waitresses in. Not really anything complex. Probably a secondary item in the cost calculations. Just make sure there’s no rivet cracks and you’re done.

  20. Old alchemical/zoroscope(sp) symbol for Mars … but you knew that.  ⊕1 anyway. (the intentional misspelling is to remember that Iran’s much persecuted Zoroastrians were quite delft with horoscopes. So, why not Zoroscopes? Y’know?)

  21. My wet dream is that Bezos and Musk are putting on a good/bad cop show, and one had to take Mars upon losing a coin flip. I’ve proposed a cage match between the two in the past, for charity of course. I find much more interest amongst females in O’Neill settlements than the conquest of distant planets. If they hear of them.

  22. Although I’m not sure he’s enough of a sophist, I could believe Musk realized cost to LEO was the problem and that it would be easier to get people to burn the candle at both ends for a launch company with an easily grasped SciFi vision. Trying to explain O’Neill’s space habitats the mid-wit coeds with diplomas in compliance studies makes them go cross-eyed. You need _some_ of them to keep the male to female ratio of the “movement” below, say 10^^^10. Gays and incels will only get you so far.

  23. You should just do what you did with Buran and simply negate these claimed advantages, that way we don’t have to listen to all the constant whining about the one guy.

    Родина-мать зовёт!,

  24. You pass by people every day, meeting, making and eating food, playing football in the streets, building racing cars or RC planes, in coding camps, book clubs, sewing clubs, brainstorming, dating, setting up telescopes to watch the stars, playing music, reciting poetry, performing mixed martial arts or whatnot and the line crosser is getting together, without your support, to solve the problem of inter-planetary habitation?

  25. Only to the *inner* question of whether we should go to Moon as path to Mars. I was willing, until recently, to stipulate Mars rather than O’Neill long term just to get Moon in the plans, as it is the start for either O’Neill or (non election cycle) Mars. Aldrin was told by Hawking to “colonize the Moon first”, so he is now also a Moon guy. But the *outer* question of O’Neill v planets, even Earth, seems unknown by many. And I see many conflicts with Sagan’s “blue dot”, as it seems to limit possibilities to planets. These are very important issues! If O’Neill is right, most of what we are doing is unguided, only right in that all things Space are right, at the very start.

  26. Hiya, Goat. At the risk of sounding like an epic pessimist? It might be easier to solve *all those problems* than to solve the political ones here. And that’s…. not minimizing what those issues are.

  27. So far this particular dream rests on how much Elon Musk wants to go to Mars. As long as he lives and has money, the Mars settlement is happening, regardless if it achieves or not its goal of becoming a 1 million people city.

    No nation or space agency has serious off world settlement plans like those, with actual deadlines, milestones and hardware being produced towards that goal.

    The space agencies all talk the good talk, but none is really pursuing such a plan. Even Artemis is a collection of good intentions with some financial support, and it may indeed work in the end, thanks to the desire of some of its participants to make it so (including competitors E. Musk and J. Bezos).

    That in itself is not a problem, because if the Mars base fails to become a city, it’s Elon Musk’s money that is on the line, and the power of such monumental changes comes more from those done by humanity as a whole.

    SpaceX reusable rockets can be used for a lot more things than E. Musk’s particular dream, and the important change is that such capability will start existing and continue to do so.

  28. Sagan endorsed O’Neill (edit: can’t find the quote anymore, was on nss site. Something like “O’Neill presents an alternate view on how to do all of this, I’m betting on O’Neill”)

  29. My positive thinking started in 1977 attending a SMIILE event. The main discouragement has been the slowness of people to *see* O’Neill, only comprehensible because of the highly counter intuitive nature of the facts. And, Mars stuff, which is so goading as Mars is a planet AND it was used to block lunar knowledge. Curious that Musk’s Mars fantasy has provided the biggest hope for now, Starship!

  30. Just about the same career track, this old goat. Majored in chemistry, but did way more than the university wanted to tolerate in computer science, physics, mathematics and its red-haired stepchild, statistics. Started around 12 or so. It was an era. Now, kids buy Raspberry Pi computers and tinker. The art is still alive! The last 50 years of fantastic near-fiction-level technology advances tho have definitely taken their toll on ‘dreaming’. Terminator II, Star Wars, Mission Impossible and an endless series of Marvel SciFi movies have seriously eroded what used to go for outward-positive thinking.  Ah, well. We’re getting old.

  31. ⊕1 … rhetorically well put.

    However, I also see that there may be a rising tide, exactly the same tide in fact that thwarted America’s (and all the other nations) manned trips to Luna: heroics evolving into humdrum. 

    The budget of Apollo overall was way too large from the citizens’ and thus politicians’ points of view.  

    Well-heeled academics propelled space-science and military eye-in-the-sky things, relatively economically.

    Considering that even with Elon Musk’s highly economical Great Big Missile family of rockets, revolutionizing the cost to get a kilogram to space, I continue to think of the economics of the whole enterprise, and compare that to either the Apollo or the Space Shuttle programs.  

    Ultimately, we have to admit this… their costs included a lot of dross-of-operations and piggy-backed also-ran investments. Admitting that we definitely have NOT invented some service, technology or operations-and-funding revolution (akin to what has happened to semiconductors, say), AND because Musk’s Rockets are only modest technology revolution, the economics of a whole-program at least on par, and likely substantially exceeding the funding of Apollo, or Space Shuttle.

    That, in the end, delegitimizes a huge manned Mars effort.

    ⋅-⋅-⋅ Just saying, ⋅-⋅-⋅
    ⋅-=≡ GoatGuy ✓ ≡=-⋅

  32. This is why we don’t see massive new developments springing up in Antartica, Greenland, the Sahara Desert, or the bottom of the ocean. There is no economic incentive to justify the cost of doing so. And unfortunately there isn’t one on Mars either, although it would be cool to see a colony there.

  33. What we have is an excess of sovereigns and rulers telling us what we can and can’t do within the lands sovereigns past declared as theirs.

    The Earth itself is far from full, but it is really small for the greed of power of a few.

    Alas, I’m afraid space won’t be any different, because there we will need each other more than any time before, and that means confining yourself to the rules of the community and the whims of the sovereigns and rulers.

  34. Dunno. I think ultimately it’ll be related to the profit-included cost of running the Spacer Flight Service.  

    Somehow, a modern high-functioning airline is able to purchase a mix of regional-to-intercontinental airplanes, keep them provisioned, staffed, maintained, fueled up, pay the dockside fees at airports all over the place, the various agencies that vend tickets, lawyers to defeat pointless and endless lawsuits. And before the Great Flight Crunch some 3 months back, one could regularly enjoy a tight-fit trip across America for less than $400 a throw. Nice airplane, too.  

    These planes cost $50 million to $150 million, last I took stock of that world. Jet fuel is 50¢/lb (about $3/gallon, or $1/liter). Planes have become amazingly fuel efficient, which is how the industry continues to keep prices low, and still make money. The only real way a plane makes an airline money is when it is chock-full of people (or high paying, but rare cargo) AND flying nearly 300 days a year.  Some airplane!

    I don’t know what it’d cost to fuel-up a spacer, on a regular basis, and keep people winging to and for with them, but i’m betting the costs could become roughly comparable. Methane is cheap.  Really cheap. And turning it into a liquid … only requires burning some methane in a compressor engine.  Nice, that.

    So, I’m kind of on the fence.
    ⋅-=≡ GoatGuy ✓ ≡=-⋅

  35. Bezos read “The High Frontier” when in high school and that’s why he’s doing Blue Origin. Zubrin came along from the Sagan end of SciFi decided to debunk O’Neill as part of Sagan’s Mars Mania. Musk got caught by the Sagan slipstream via Zubrin and now we have Blue Origin pursuing solar powered free floating space habitats constructed from lunar materials, rotated to produce full gravity VS SpaceX gangly transhumans with long spindly legs and neuralink helmets powered probably by nuclear reactors, terraforming Mars or something like that.

  36. If it blows your mind 1/10th as much as it did mine, hold on! I had been an amateur astronomer since age 11, majored in Physics, was very interested in Space, and had NO CLUE.

  37. if it is cheap enough a new demand will appear. If we can fly vegetables with airplanes and LEO is the same price why not build space solar, for example? I am afraid, the best case will be the other way around 20x the price of airplane. That still would be immensely better and cheaper of what we have to day. Hell, i would even for for a space ride with a bit of financial planing and saving.

  38. “bodies having substantial surface gravitation, sufficient insolation,
    untapped-and-likely-near-limitless mineral and raw-materials resources,
    area to stretch out, and a modestly protective atmosphere” Of course you are pessimistic! You assume O’Neill is incorrect about all of these issues, without any comment. O’Neill Rotating Habitats, even the early Globus designs, have any g desired, utterly superior insolation, astronomical material resources, enuf room for trillions, and protection that is designed, not waiting for the next big flare. I hate to ask this, but your misspelling requires it. Have you read “The High Frontier”?

  39. You are complaining about the Mars hype too, so I accept your criticism as directed to both sides. When O’Neill gets 1/50th the coverage of Mars in the general coverage, I will stop!

  40. So is the sea. Above the surface and below. Then there are the deserts and the wildernesses. 90% of this world’s surface that is basically uninhabited.

  41. Where is the pend up demand for space launches? If you build it, will they come? I don’t know.

  42. Yep.

    But for a dry run, for testing, doing a loop around Luna and back here to test out the equipment, is a good deal.  

    International agreements or no. 

    ⋅-=≡ GoatGuy ✓ ≡=-⋅

  43. Having cheaper, reusable launchers is just the first couple of miles of a very long marathon.

    Don’t get me wrong: it is a big thing that we will be able to launch more stuff and people to space.

    But then we will need to learn what we can really do with that, not just fantasize with Golden Age of science fiction dreams, when people knew very little about space, and it was therefore imagined as a new version of the Old West. It isn’t.

    As others pointed out, space is very unforgiving. The moon dust is a nasty abrasive stuff that will probably get us really sick in the long term, same as the perchlorated regolith of Mars. Space radiation can cut short the lives of the settlers too.

    Low gravity may also be a deal breaker for life in other planets, producing malformations and really sick babies. Life in other planets won’t be a Space Geek Disneyland, but probably an ordeal and a chore, if possible at all.

    It is possible that the lofty dreams of cities on other planets come to a halt, when people realize after the fact how harmful and maybe implausible living there would be.

    That could result in demoralizing our space projects and put them in the freezer for a while, or if we are smart, in making lemonade out of lemons and emphasizing settlement of actual space, where everything there is brought by us, and focus on using space rocks only as resources. Something we could do mostly with machines and a few very focused applications of human handwork.

  44. Here’s an idea, Dan.
    Cook up a nice list of linkies that point to several not-firewalled articles.
    Articles that explain O’Neill’s visionary plan.
    Articles with breadth, depth, detail, pretty pictures.
    Then… every time you post one of these lil’ gotcha-comments, cut-and-paste the list of linkies from your saved stuff.
    I think you’d get downvoted less.

  45. ⊕1, merely for (ahem) stealing my party line: why ponder the near-cataclysm of dealing with comporting humanity to Mars in the short term, when we cannot seriously even comport ourselves (by rocket, let’s say) to Antarctica, to set up camp, robotically extract minerals and dig thru one of the immensely dry “dry deserts” that are down there.  Weather is positively tropical compared to ♂. The goal, of course, would be to use the comported equipment and robots to create enough fuel and oxidizer to make the trip back, with the hopefully re-used pod . right?

    ⋅-⋅-⋅ Just saying, ⋅-⋅-⋅
    ⋅-=≡ GoatGuy ✓ ≡=-⋅

  46. I’ve taken a different stance: let’s see what a real, flying, people-and-rocks carrying version 2.1 is doing, before planning the scaled up version of 0.1 (which is where we’re at today). You know?

    Talk about counting one’s chickens before the barn for the hatchlings is built! 

    ⋅-=≡ GoatGuy ✓ ≡=-⋅

  47. Rather nice numerical catch, Mr C.  
    Worthy of a ⊕1

    However, note that things like “engines” don’t conveniently scale as one might wish. That, and in a sense, the lesson of duct-taping 4 rockets together as an incompetent mental exercise also adduces “the scaling problem”.  One can certainly multiply the baseplate area by 4× with 4 bailing-wired-together ships taking off at the same time. But the payload only also scales by 4.  

    I think that is the real gotcha.  

    Kind of like a boy’s dalliance with “model rocketry”. One learns early on that while a so-called bottle rocket (a few grams) might accelerate at over 100 G out of the bottle for a few milliseconds, as one invests-and-learns in larger rockets, their acceleration anti-scales with size. For fairly obvious math reasons, one can show that V ≈ M scales with ‘d³’ (dimension cubed).  But that the thruster(s) only scale with (d²), the area of the base. 

    ⋅-⋅-⋅ Just saying, ⋅-⋅-⋅
    ⋅-=≡ GoatGuy ✓ ≡=-⋅

  48. Someone (not me) downvoted .. I think Dan because your chant is getting repetitive.
    This is not to say it is a bad thing to chant, or that you’re a loon or something.
    Just kind of thin on the gin.
    A weak drink.

  49. Maybe not (radioactive), but certainly a long-term and decidedly serious health threat.  

    I mean, just think about it: ‘dust’ created by endless pommeling of the pre-existing stuff-of-Luna with more incoming stuff-from-space, without any atmosphere (of note) to weather away all the sharp bits, and to passivate all the mechanically-created fracture radicals on every surface down to the nanoscopic. Then, assuming the macro-bombardments were to have stopped a billion years back (they didn’t), then there is the billion-odd years of unquenched cosmic rays, solar gammas, local supernovæ fragment relativistic washes and other ‘incoming’ ionizing radiation.  Well, at least that kind goes to quench the free radicals. But in turn, every last wee bit of mineral crystal to a depth of several meters, is irradiated with profoundly energetic motes of matter and energy.  

    ≡ Does this make regolith radioactive?
    ≡ Might. 
    ≡ Probably does. 
    ≡ Almost certainly couldn’t not do so.

    What remains though, even a billion years out, is that all those bizarrely fractured sub-µm particles are just as crazed as when first broken off their mother bits. Just now they’re irradiated immensely. 

    — Yah.  
    — Fixing that is the problem.

    ⋅-=≡ GoatGuy ✓ ≡=-⋅

  50. Short answer: yes.
    Long answer: Of course.

    No, seriously! Although McFinnegan bubbles might seem like the most flexible path to Humanity’s space legacy, it seems to me at least that bodies having substantial surface gravitation, sufficient insolation, untapped-and-likely-near-limitless mineral and raw-materials resources, area to stretch out, and a modestly protective atmosphere … are better than space bubbles, overall.  

    Better SciFi, too.  
    Thirty euros a hectare, on sale today!  
    Get your Mars homestead now!
    Reserving your seat on the Startship 10 … just fill out this waiver.  
    No, we do not offer life insurance.
    What, you crazy?

    I WILL SAY THIS -— it bothers me to no end that I end up sounding like a pessimist viz-a-vis space travel, Martial colonizing, McFinnegan pod-farms, and so on.  

    Maybe read what I just wrote in reply to Dr. Pat.  
    If you “get it” below my embittered rhetoric, maychance you’ll see why I harbor this cynicism.
    O’Niel pod-farms. 
    Got it.

    ⋅-⋅-⋅ Just saying, ⋅-⋅-⋅
    ⋅-=≡ GoatGuy ✓ ≡=-⋅

  51. It is just as you say, that causes me to question the unerringly pro-positive “faith” the puppy-dog-enthusiastic community-of-believers-and-journalists tirelessly employs to disseminate the propaganda of Musk’s Rocket Vision to us all.  

    You (I, we) think about “what it takes to make an airplane”, which is a hugely mature construction and industrial technology manufacturing business. Airplanes in concept aren’t even that complicated!  The magic is in the metals, the metallurgy and the massive engines (which really are pretty magical too).  But simple. Make a tube, affix wings and a tail, a couple of powerful thrusters, and fill it full of seats and air conditioning.  Voilá. A jetliner. (Tongue-in-cheek, of course!)

    With that same Musk-ian simplification, one can describe an intercontinental ballistic missile massive rocket people-and-product shipper. Scale the vector drawing of the still-as-yet-unflown not-really-a-Starship by 2× (dim) = 8× (volume), find an unsoiled napkin and gin up its specifications.  Secretly (in the open) release its specs. Endless armies of enthusiastic puppy-dog journalists will chew the numbers, come forth with banal extensions, and grand plans for populating the Universe one asteroid at a time. 


    So, how then, with a device substantially larger than an airplane, more powerful and critically less safe … does one make it for ¹⁄₂₀ the price?  Just asking…

    ⋅-=≡ GoatGuy ✓ ≡=-⋅

  52. Also part of the point is something close to unfettered capitalism. There are few reasons to have the stringent environmental protections on Mars that we have on Earth. Don’t want that on Antarctica…

  53. We can build Starships on Earth, we can build big buildings on Earth! Just think what we will be able to do in Space! See G. K. O’Neill for instructions.

  54. Hmm – yeah, but if they didn’t stretch the conical portion, just boosted it up by extending the cylindrical portion, we could approximate the current volume as 3/4 height cylinder topped by a cone, so the current volume is about (0.75+0.25/3)*H*A = 0.83HA. Stretching the cylindrical portion to 1.75H and the area to 4A, we’d get (1.75+0.25/3)H*4A = 7.33HA, which is 8.835x the volume.

  55. So far as I’ve read, lunar dust isn’t terribly radioactive. Abrasive and reactive, yes, and it tends to get into and cling to everything, so it is a health risk, as well as a major risk to equipment.

    The video you link to doesn’t appear to cite any sources to back its off-hand claim about dust being radioactive enough to be a problem. (Pretty much ALL natural matter has some slight degree of radioactivity.)

  56. I love Antarctica and have worked there, and have long thought colonizing Antarctica could be a good thing – but the chief downside I see is that it is simply too close to other humans. This is especially relevant if the greatest threat to humanity is other humans, as I suspect it is.

  57. You might as well look at colonising Antarctica instead of Mars. The continent wants to kill you as soon as you step out of the door as much as Mars does, but at least there is still gravity, atmosphere, plenty of water, and proven mineral reserves. Its only one tenth the surface of Mars, but is a whole lot closer.

  58. The bigger issue is that the height is unlikely to be doubled, as @ToveraVashini explains, and all the rest of the article relies on this false assumption.

    More likely, the height will remain about the same, maybe a bit taller, and with engine upgrades you might get x5-6 the capacity, not x10. It’s also unclear how much lighter they can make the construction. The B-core slab may not be very relevant, because it’s only lighter compared to conventional building construction, and that’s far from weight-optimized. But rocket construction is already close to minimal weight. They may be able to shave off some thickness, but they’re limited by load and strength constraints.

    All in all, I would guess the version 2 may have ~500-700 ton capacity, not 1000. Though granted, that’s not a big difference.

  59. Meanwhile, we have the oft-repeated claim that SpaceX can build a reusable suborbital rocket for 1/5 to 1/20 the price of a reusable jet airliner.
    Maybe Elon should just go into the jet making business. Show them how to do things?

  60. This would mean the area of the cross-section would be 4 times higher. If the height was also doubled then it would have 9 times the volume. 

    4 x 2 = 9?

    Brian, you need a new calculator.

  61. Won’t happen in our lifetimes, and most likely ever. No reason for it. Planes take people places like Disneyland. We have 8k TV and 7.1 surround sound at home. We have the ability to do a lot of things, but we don’t do them.

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