Virginity considered harmful

Timothy Flanders recently wrote "With Humility, Women Uplift Themselves and Sanctify Men". Under that (laudable) headline, he mentions that state of woman which does nothing for men: virginity. More to the point I question this state's humility.

There are points where virginity is necessary. If everyone around is immature, it is wise to suppress one's desires in that direction. If there are no legally-available and competent partners, likewise. Those suffering from SSA or from worse are also advised toward celibacy. But... these situations share a thread in common. They're abnormal.

There are arguments that celibacy uplifts woman, which arguments would apply to men as well. "Sex is a distraction." And so it is... if that's all you're doing. But in a healthy society, it's not. It's the start of a family. Family is no distraction from life; it is the whole point of life.

Promoting virginity in the face of a hostile world is like promoting killing the soldiers of an invading army. Promoting virginity for its own sake is like promoting murder. This isn't humility, it is selfishness.

BACKDATE 2/1/2020.

AAAAAND POSTSCRIPT 2/11: This post - Flanders now reminds us - is anathema by the Council of Trent. Believe it or not I do take Trent seriously.

If I was to argue celibacy's case in this context, I'd say that although Christianity sequestered some women out of The Dating Pool before their time, at least they didn't sequester them to Conan The Cimmerian. (The nunnery also locked the homosexuals out of view, as did the monastery.) Christianity forced normal single men to struggle that bit harder for the remaining [Christian] womens' attention. These men strive to be good providers for these women, rather than to be the one Alpha who would monopolise all of them.

But I don't know. Flanders hasn't made that case himself, preferring to quote edicts. Maybe there's a Catholic author out there who can argue the point instead of (implicitly) threatening me with terms like "hate" and "assault".

The Eemian out-of-Africa migration

I knew there was some West Eurasian backwash in African populations, during the last Ice Age; I further presumed there’d be Neander in that.

The article confirms the Neander component of that backwash “over roughly the past 20,000 years”. It also confirms that these were the western sort of Neander, not those Neanders (much less Denisovans) contributing to the Orient.

But I’d thought its initial mix would have come wholly from the canonical out-of-Africa 70kBC, backwashing to the Horn and Algiers over the full ice-age 13kBC. This article is talking about a full out-of-Africa around the Eemian, 130kBC – which didn’t wash back. At least, not directly at that time…

I did know of some trace of that Eemian pulse in Eurasia. Specifically: that trace is modern-human in post-Eemian western Neander corpses, recently exhumed. Now we’re seeing it back in Africa too. So it wasn’t just a one-time meetup into a population subsequently slain, like that Ice Age hybrid of Romania. Part-African hybrids were the rule in west Eurasia 120k-70kBC.

This hybrid wagons-south DNA is now expressed over a good deal of Africa; they’re talking modern Yoruba. Researchers needing a baseline for ancient DNA should use the pygmies instead.

Of interest to Africans: these Neander genes in Africa were for “bolstering the immune system and modifying sensitivity to ultraviolet radiation”. So some Eurasian plagues were roaming around Africa during that ice-age. Also (I guess) some Africans were considering a move into local forests, which the Neander DNA would have helped.

UPDATE 8/6 PM: There were earlier pulses into Europe, which didn't wash back.

Ramjet house

Say we have a nuclear missile flying around Venus atmosphere every six hours, on a mission for a couple months. Quarters are (near-certainly) too cramped for us primates and all our primate needs but hey, we got robots. What can its robots do up there?

One important option, for the ramjet at, oh, 75 km altitude, is to drag OTHER ramjets (even scramjets) up to sufficient velocity. Such of the former would fly until approaching lower-altitude and slower craft, and drop a tether-and-hook to catch them. (Depending on the rubberiness of the tether, that seems a significant boost in g-force. Not to mention that the lower vessel is looking up at an atomic reaction. I'd hope said lower vessel is not carrying anything fragile, like monkeys.) Here's Alberta Oil Peon:

Have your ramjet slow to about its slowest speed, and match altitude with the daughter craft. Have the daughter craft do a brief intense fuel burn to match speed with the ramjet, and latch on. Then ramjet cranks up wide open to haul daughter craft to upper limits of atmosphere.

Many such lower vessels are spacebound. Once at Mach 3 and 75 km they switch to their own battery-powered single-use ramjet boosters. When those boosters have done what they do they fall back to Venus, to recharge by solar, and the Venerean flotilla can catch up to them later. The battery-operated boosters meanwhile have set their passengers for such gravity, air-pressure, and velocity as trims delta-V toward low orbital 6370 m/s or elliptic 9455 m/s. For that, 1000-1800 ms^-1 is better than 100. Might not need a rocket at all.

For lower altitudes, ramjet longterm craft might be surveying the surface. Maybe there's a rescue-mission in the offing. Maybe someone dropped a satellite or a balloon or an aircraft with some valuable material. Maybe they're looking for ores.

UPDATE 2/24/21: Now I think on't, classic Pluto was always a S.L.A.M.: a low-altitude solution, that might not get over the clouds here. Molten-core Pluto should supply the heat to run it higher... and faster.

Titan doesn't need rockets

The Tyrannical Rocket Equation reigns o'er all the planets from Earth to Neptune because of a velocity gap: between what a furthest ramjet gets us, and what a nearest orbit needs. Above a given altitude, there's insufficient ambient air to feed the ramjet. And still, Wi Tyu-Lo (and slow) to get into orbit. Although there's questions about Earth.

Propose a planet with low gravity yet high atmo. Such may well hold for Venus. It certainly holds for cold planets. We can start haggling over Titan. If that ever gets colonised, its colonials won't need rockets to visit the other Saturnine moons. They'll just need good batteries.

The Venerean nuclear ramjet

I know this sounds like a porno title but hear me out.

In Venerean conditions a ramjet requires hundreds of megawatts to superheat the air, so (at 458 * area wattage) we're still not solar-powering this thing.

But nuclear Pluto emits little "waste heat" since all the hotness is for blasting back compressed air coming at us from the front. When it's not running, it flies with the flotilla or is floated in the clouds, and is loaded there; it is assisted into its Mach 3-6 run by single-use thrust, either chemical rockets or some battery-powered aeroplane. At first...

Once aloft the ramjet circles the 40075 km equator - rather, the 40515 km 70km-altitude circle - at Mach 3. 40515000 / (3*315) = 42873 seconds. So an even twelve hours. More likely half that, at Mach 4.5.

Project Pluto

Just when I'd thought I'd fished out the possibilities of Venus' atmosphere, I found a new one!

With current tech, the "Eternal" Flotilla can keep decent freight (like us monkeys) at 11 AM for about as long as the turbofan is supplied with fuel. Even lighter loads borne by propeller stay up only if the 'planes are assisted. (UPDATE 8/17: We might hope for floating chargers.) To spin that propeller to jet-like force I considered an enclosed nuclear habitat but last Sunday I realised that would be energy-inefficient - like to the point that other Venereans will simply find better use for their hard-won fuel.

But then I thought - hang on, aren't there things called 'ramjets' that SF authors were proposing elsewhere? To hell with fuel or any sort of expendable propellent - use the atmosphere! So how about a nuclear ramjet...

Turns out I am not the first. In the early 1960s the US proposed just such a monster: the Project Pluto. Being the '60s of course this was mooted for a wider project of bombing Russians. And then the US decided that ICBMs would do better at it. Since then in 2002 some idiot proposed this for Jupiter (pdf) not considering that planet's absurd radiation.

Over Venus, I haven't done the maths on how Project Pluto would work. I can report that it would set off on its months-long passage over the planet at Mach 3-6. Again, no maths, so I am not calculating Mach 1 at whatever airpressure of mostly-CO₂; let's say it's 315 ms^-1. I'm not considering scramjets. I'm even leaving aside how we power it. We just know it's faster than the 100 ms^-1 fanning the equatorial clouds. And we want Mach 4.

So this isn't the 11 AM perma'plane, either. Solar/battery was too slow; this one's too fast. And I expect not to be stuffing the innards of this thing with human life-support. But we can still find uses.

BACKDATE 1/29/20: I'd thought of the ramjet Tuesday but didn't get around to constraining it.

UPDATE 2/24/21: Molten-core Pluto should supply more heat. This, to run it higher and faster.

Unborn worlds

John Tarduno at Rochester University [h/t Science Daily] has constrained how young planets might or might not run a dynamo in their core.

Earth’s present core is separated between a whitehot inner layer and a churning outer layer; and it is this which raises up our magnetic shield against our ever-heating sun. Tarduno says that Earth got our shield only 565 million years back - less than four billion years after Earth's formation.

Tarduno further assumes an earlier dynamo. For that he proposes that the Theia impact, besides throwing up our moon, also had mocked up this dynamo, via a shock of magnesium salts sinking to the bottom. But this dynamo had frozen out earlier. [QUESTION 3/15 - Mantle dynamo? NO ANSWER 4/9 - How would we know?]

This 565 mya point is in the Vendian era I believe. Earth had life during the Vendian but it was miserable life, mostly oceanic. Jellyfish and sponges were about as good as it got. Lichens on land.

This means that planet hunters cannot count on a dynamo to protect young Hadean / Venuslike planets. By "young" we include anything around a star 1.5 solar masses and up, like Procyon; they go nova before four billion.

Science-fiction worldbuilders are pretty much stuck, as well. Those tundra planets are likely irradiated as well. Terraformed Hadean planets might be okay, since they're living during a bombardment... until the next big one hits.

TARDUNO 7/25/22: He's finetuned 565 Mya to when the old core failed. 550 Mya is when the new core started up again. The rest is history. More exactly palaeontology.

Permanent flotilla considered wasteful

I'd mooted power needs in spacecraft and aircraft. For aircraft I was more interested in surface-area than in weight; but weight did turn up for periodic energy requirements. We're talking very long term flights so: no fuel, just energy-powered propellers.

There is a word for kilowatts per kilogram. Rather: for the reverse. This is specific-mass - "alpha" - we want less of it, and what energy we do get needs to be electric and ultimately kinetic. Batteries deliver some awesomely low alpha - well below one (1) is attainable - but as Hop informs us, batteries run out. Still, a good battery lasting about a week is fine for Forever Flotilla when it's not 11 AM. Assuming we don't want to lift very much because, again: no turbo-, just -fan.

Some nerds who have been huffing much meth have been talking 0.04 or 0.15 α but, good G-d. 3 kg/kW by contrast seems practical. With a hat/tip to Project Rho, in the 1960s they used to consider 18 a good day.

Nuclear power plants are about the only way to generate this much power to our fuel-less fans. Nukes give out a lot of power for the space and fuel they take up - because the extra heat they give off can be recaptured. Nuclear-powered submarines, living under the sea and needing a premium on space for the canned monkeys down there, do not recapture this heat. They are widely bemoaned as inefficient: 13000-15000 kW. This is from 900 tonnes of weight. That alpha is in the high 60s. YECCCCH! It's the same principle as for space (again: Hop's rant absolutely inspired this one): here's the SAIRS from 2004. UPDATE 1/28: unless we're living in a Pluto ramjet lol.

One might moot some cockamamie contraption like flying vertical towers to recapture that heat, but it would have to divert that heat to turbines of its own, so why bother. In Venus atmo one can assuredly get better use of potential energy where the reactor is floating and coptering, not flying. That's down in the clouds, rather BELOW them.

In the meantime the 11 AM Flotilla will be an ad-hoc affair, pending the production of low(er)-alpha self-contained monkey cans. They'll use it during port-season, to/from Earth. I am not saying it won't happen - it might well be a prereq for getting to Venus in the first place - but the US Navy will assuredly want dibs on this tech for its own submarines, before any of this stuff gets out into space.

UPDATE 8/17: charge it up midstream. Still not buying it for nonturbo.

Corona, the least interesting virus in the world

I remember reading about Corona Virus - and Rhino Virus - two decades ago, when I caught either flavour of common-cold. Then I decided that this sort of distinction was autistic and made me look snottier than (even) a cold victim should look. Earlier this week I heard about Dos Equis Corona-chan making its way around China... like SARS did.

China is freaking out, again. And 4chan is making a show of freaking out too. Because that is what 'channers do, they troll the normies.

It is generally wise to limit exposure to the common cold. The cold itself is no fun to live with, and it can open the airways to bacterial pneumonia which you REALLY do not want. So do keep some soups and some cold-eeze around. Do wash your hands. Do ensure you take deep breaths (in your own space) to air out those bronchials.

Otherwise stay frosty, my friends.

Mach 15 world?

It was long a staple in science-fiction that Mercury was locked into rotational resonance with its own orbit around the sun - although I doubt anyone serious ever imagined that this (visibly) tiny planet could hold an atmosphere. Some years back I read and enjoyed Comins' What if the earth had two moons; among which parallel Earths, was one locked into rotational resonance with its own orbit around the sun. Recently James Trefil and Michael Summers in Imagined Life have mooted the same. Now that we've been seeing plenty of close-in Earthlike planets, and even one around Proxima, it's time to constrain how a habitable such world would be possible.

The reason Mercury was assumed tidally-locked so long was because nineteenth-century models explained how such worked out for our Moon. (Mercury turns out to spin:revolve at 3:2, which isn't so far off.) We will rarely see tidal locking for further-out planets like Venus and Earth. So, for our tidally-locked hypothet: assume a tight Mercury-like day-year, and similar distance from a Proxima-like star.

Oh, they'll just be living on the prime-meridian, say the naïve. Even Clark Ashton Smith used to say that, back in the Mercury days. Trefil and Summers note that if the place has an atmosphere, that atmosphere will be moving - like Venus' atmosphere moves. On a sun-facing planet, the air on the sunny side gets hot and on the darker side, not. This leads to the hot air rising and flowing outward; the cold air sinking, and flowing inward.

Trefil and Summers pp. 120-1 claim that the planetary wind does this fast. Mach 15, they say.

This piqued my notice because I'm proposing (elsewhere) 11 AM Flotilla. Some amazing material scientist could run an scramjet against a Mach 15 stratosphere, even with Earthlike insolation (UPDATE 2/3 - material science is, yes, key here; X-43 is only at, what, Mach 9?). As for carrying that Orion nuclear rocket, I'd look into inlining its architecture with that of an aircraft - I see no way a Mach 15 perma-plane drags this thing behind on a net.

The question then boils down (heh) to: how long is this planet going to keep its atmosphere. The term is atmospheric escape (pdf). For thermal alone I think I'd take Figure 1.6, with a look at the planetary surface escape-velocity. From that I'd subtract the wind velocity. Given a speed of sound 340.3 ms^-1, Mach 15 is 5104.5. Earth-escape is 11200. Subtracting the one from th'other, I'm looking at atmospheric escape-velocity 6100 ms^-1 at the trailing planetary coma. That's also assuming exosphere 1000 K which I'm unsure we can. A few good flares would nuke this atmosphere but good. So we'd have to constrain Mach 15 World's sun that it not flare so bad. And that the planet has a decent spinning core, even if the planet itself isn't spinning on the outside.

I wonder if the whole question be moot. The authors forget exactly that these are close-in planets - their rotation is not as slow as they assume. For Super-Mercuries we must assume Coriolis. That distributes the wind more evenly around the planet.

I do not see in these Earthlike simulations where the wind reaches Mach 15. They reach instead a (handsome, admittedly) 75 ms^-1. The slower wind and the less-extreme heat differential further allow cloud buildup on the sunny side, reflecting that sun back away. Which brings us back to an ocean-world.

Maybe Trefil and Summers were thinking of the habitability of superMercury near an orange dwarf. That would explain why they speak of silicon rains on dayside. But as mentioned, I don't think they're keeping an atmosphere at this windspeed and heat.

When worlds collide

In 1933, Philip Wylie and Edwin Balmer serialised a science fiction book, When Worlds Collide. They proposed that an orbiting pair of rogue planets was on its way to Earth on a hyperbolic trajectory, which our system would bend into an ellipse of period eighteenish months. The pair would then pass by Earth (and Luna) again, ousting them from our orbit; instead dumping its own smaller planet in our stead and then, I don't know - maybe going off to smash Mars.

Presumably Earth Two would inherit a highly elliptic orbit of her own. I don't know that the authors sorted out the Newton. They did, at least, figure out they could use the Orion Rocket as an Ark [UPDATE 3/14/21 - if you don't ask how to land it again]. I didn't read the book. I did see the 1951 movie... it stank. Melancholia wasn't good either. But anyway.

It occurred to me that something like this has happened only 70000 years ago. Scholz's Star (-system) whizzed by our Oort Cloud. If true that's close enough to be measured in Astronomical Units: 52000 times as far from our Sun as our Earth is.

Scholz's Star isn't much of a star. It is a red dwarf with a brown dwarf companion. We know it came by because it is (barely) a star, which can be seen (now) 20 light years away. UPDATE 8/15/22 And it probably didn't get all that close anyway; they're now talking 1.08 light-years 80 kya. NEXT

Gliese 710 is more relevant to my purpose here. It is a 0.6 solar-mass orange dwarf; it could well have its own planetary system. It will be coming within 14000 AU. Although we won't have to worry about this one for another 1,281,000 years.

I do not hold the 1.5 million year span encapsulating both Scholz and GJ 710 as a special span within the 4567 million years of our solar-system's existence. In fact, this span should be one of our quieter spans, given that we're not in the Galactic Ecliptic and that the rest of the Galaxy is winding down (I mean, until Andromeda crashes into us, but our personal system will be cooked by then). Given the proportion of stars, red-dwarfs, and rogue planets out there - not to mention the hyperbolides - it all leads one to wonder what else might have drifted by, not so visible.

And suppose a 1.5 solar-mass star rammed through here within, oh, 5000 AU millions of years back - with all its own retinue of large orbiting planets, and let's add a Proxima-class red dwarf. This has implications for Planet Nine. Maybe we had one. But it got stripped away.

UPDATE 12/7: Comins on Cerberon. We (Comins then, me now) hadn't constrained how often other stars might get here, nor how close they'd get to us. So I'll put a marker: we're all safe within 1000 AU of Sol, until Andromeda merges with us, by which point the Earth will be a radioactive dry husk anyway. Almost all planets this far from the Core are safe, however far that may be.

OnePeterFive versus Augustine

Richard Dawkins has a book out: Outgrowing God: A Beginner’s Guide. The theists are approaching this work with all the decorum and sobriety as one can expect. I'll take as text for my sermon tonight, David Mitchell at the ultraCatholic site, OnePeterFive [my bold]:

It is divided into two parts, the first being, after a fashion, theological, and the second claiming to be biological and scientific. In the theological section, the author presents his philosophical, theological, and moral arguments against the existence, justice, and goodness of God; in the second, he attempts to demonstrate that evolutionary theory — which he, without demonstration, labels “a fact” — has disproved God, or, which he seems to think is the same thing, has rendered the hypothesis of the existence of God unnecessary.

Since Mitchell professes to dislike bad logic and sloppy thinking, he should welcome a rebuttal to the same when it comes from his own pen.

No biologist debates about evolutionary theory as such. Debates remain about Darwin's (primitive and impressionistic) understanding of said theory, mainly as an historic curiosity. Although this nineteenth-century heir to Aristotle is coming off better than you'd think.

It is not up to Dawkins to demonstrate the proof of a scientific consensus. This misrepresents where lies the Burden Of Proof. To ask an interlocutor to shoulder such a burden as are not his to bear, is to waste his time - and ours. This is why we dislike sealions. It is up to critics like Mitchell to challenge this consensus, if they can. (Spoiler: Mitchell is not a biologist, so can't.)

But wait! there's more!

On page 30, Dawkins tells us that the Hebrew word almah need not mean “virgin,” but that parthenos does always mean that. (He is wrong about that; parthenos can mean young woman, but not in this context.) These are the words used in the Hebrew and Greek texts of the Old Testament, respectively, in Isaiah 7:14, which says “a virgin shall conceive.” Almah can mean “young woman”; so, for that matter, can the Latin word virgo, which can also mean “virgin” and which St. Jerome uses in his Latin translation, the Vulgate, in this place. Dawkins tells us that rendering almah into Greek as parthenos was a “translation error,” which “spawned the entire worldwide myth of the Blessed Virgin Mary[.]” In fact, all three words bear both meanings. (So where is the “translation error”?) But the authority of the Catholic Church is sufficient to tell us which one is the correct one: the correct translation of almah, parthenos, and virgo, in Isaiah 7:14, is “virgin.” So much for Dawkins’s comparative linguistics.

Am I the only one here who sees the circularity of this argument?

The text says X, in an ancient language not easily comprehended. Researchers into that text's time and place (Isaiah's Jerusalem, 700ish BC) have agreed it means A in translation. The present Jews, also, say A - but we can ignore them. Dawkins - having no dog in the Christian / Jewish debate - with the Jews, sides with the researchers saying A. But here are some gospels by heretics from Judaism, adopted by schismatics, which say it means B. The Church affirms B. Well fine then - let Catholics affirm it as B.

But you, Mr Mitchell, are approaching Dawkins as an historian. You need to prove that Dawkins is wrong about what Isaiah was saying to his own people in his own time. That means you need to wade not just into Biblical Hebrew but into Judaean history: to prove that despite that X looks much like situational oracle A, Isaiah meant to deliver the messianic prophecy B.

Which you didn't. So much for you.

The whole Mitchell essay is of a piece with this. Straining for gnats like the precise meaning of almah / parthenos; swallowing camels like the authority of the Catholic Church. Wait 'til he gets into how the sun stood still over Fátima.

On topic of Aristotelians I have recently been alerted to Catholic teachings going back to Aurelius Augustinus, late of the city Hippo in Africa. I cannot find that quote mooted around by Expanse fans, scil. that God gave us two texts, creation and scripture - which is a pity, because I quite like this quote. I did find summaries to that effect (with reference to the Book Of Nature: pdf). Pertinent here, which Augustine did say:

If they find a Christian mistaken in a field which they themselves know well and hear him maintaining his foolish opinions about our books, how are they going to believe those books in matters concerning the resurrection of the dead, the hope of eternal life, and the kingdom of heaven, when they think their pages are full of falsehoods on facts which they themselves have learnt from experience and the light of reason?

Mitchell, OnePeterFive, and Christians generally would do well to heed these words of one of our more illustrious saints.

Lost tribe

Latest genetic news: West Africa, 6000-1000 BC. h/t hbdchick, as ever. And Razib.

They claim in an offhand remark that the Iron Age started 1500 BC there. That is news to me. I'd always thought the iron smelter was a Late Antique innovation on that side of Sahara. If not, then someone needs to write an article about that.

[UPDATE: 1/23 8 PM MST - Wiki points to Nok and Djenné-Djenno, in the Nigeria region = 500ish BC. Hardly late Antique - so, mea culpa. In interest of selfdefence this the Bagastan, intermittent Aztec apologetic site, is not such a site as makes civilisational judgements based on metal-preference. China, for one, entered "the Iron Age" later than Africa because it never lost bronze so didn't need iron. I might say the same for Perú. Still - back on track - I retain an interest in claims for iron smelting anywhere 1500 BC.]

I am impressed that the scientists could get any premodern genetics at all from the swamps of Cameroon, but that's the revolution in this science we're living in.

The tale being told is of a population 1/3 huntergatherer, 2/3 paraBantu. They were (probably) not Bantuphone themselves. But I'd bet they spoke a Niger-Kongo language, related to that.

The hunter-gatherer third survives in more undiluted fashion to this day: as pygmies. These are a different branch, who speak Bantu now. [UPDATE 1/23 again: Steve Sailer says some don't.] In recent times they were on the fringe of Cameroon Bantu society, and adopted their language. I suspect it went similar in the Bronze Age.

I'll also go out on the limb that this group weren't a strong group, mentally or culturally. They later would get swamped by the iron-wielding Bantu.

Elder Magyaria

Eurogenes last week posted some stuff we already pretty much knew about the Magyars. To whit: that they look like the local Transylvanians today, but that they were heavily Uralic in the Middle Ages.

What's new is mainly the pie-chart, showing a clear plurality (38%) of Finno-Ugric male DNA signature "N3a". Another 25% is evenly divided between Germannic I2a and Scythian R1a. That 6% R1b is to be presumed Dacio-Celtic, and/or a general European substratum. (Pity we no longer have Appian XXIII.) Another quarter is C2 or G2a, whatever they are. UPDATE July 9-15: R1a may be royal Álmosid; R1b and G2a both were part of the old homeland mix.

There's 6% J1, from I-don't-know-what. I don't think the Arabs got this far northwest (unlike Turks). So maybe ancestral Neolithic Balkan.

I was poking around today at the "Greater Hungary" and found something of interest back home. It seems that a friar, one Julian, also knew that the Magyars were different, and went off to Muscovy to go look. There he was directed to a small tribe who still spoke a language he could sort-of understand. But unfortunately before he could return to take decent notes, the Mongols had showed up in the meantime. They did not survive.

A looming question over Hungarian studies is whether Julian had met some real Magyars, or had stumbled onto Khanty / Mansi territory. Ugric linguists (among which I am not) tell me that these are the surviving languages most-related to Hungarian. It appears to me that the best way to sort this out is to back-trace a proto-Hungarian language without all those later European accretions - starting with Albanian, Romance, Greek, and the later forms of Slavic. Earlier Slavic or Balto-Slavic, I don't know. The Kievan Rus were on the way west, and by 1200 AD even the "greater Hungaria" was assuredly on its own way toward Russification.

The first space factory

Chet Richards recommends a manned space factory - implicitly, an Earth orbiting factory. (h/t, Sefton.) Richards wants this for assembly of other orbiting satellites.

Two important words missing: "gravit-" (and "mass") and "shield" (and "radiat-").

His case is for building larger Low Earth Orbit satellites. Since he is saying naught special about radiation, he is using the innermost Van Allen Belt for blocking that. So, his range is 340-640 km. This will restrict the factory to making fellow LEO satellites. UPDATE 11/23: The best play is for a scrapyard.

As for gravity, he allows for zero-G assembly. I would propose Spinning The Drum for the crew on those off-hours. Although, crew-friendly living-quarters is one of those components as can be assembled on-site.

I should also like another factory built, and in part assembled, by this factory, and run up to between the VA Belts - 12000-13000 km up. This one would be better shielded. It could reprocess space-junk and asteroids for raw material as doesn't come up from Earth. It could build garbage-scows to start clearing the largest of the space turds off Earth's orbit. It could even make and restore photovoltaics. And this one could assemble even greater vessels, to build stations at EML4 and EML5 ("yeeagh!").

In the meantime: good start.

Chinampan

This morning I allowed for moist toroidal farms over Venus. I concluded they cannot carry much water before sinking. But the farmers still want a central reservoir. So let's try this again.

This is an agricultural torus with a difference: a great, gold-covered balloon is tethered above it all. With that, the torus is a third filled with water.

We needn't just let the water sit here. We can stock the water with various freshwater animals like koi and tilapia, and snails. We can even put some Nahua- (or Otomí-) speakers on it to farm its surface by chināmitl. So it too shares a (dry) central Tlatelolco.

These provide watersports for tourists. Lakefront property here is the most precious real estate in the Venus tier.

Cash crops

As time goes on over Venus, some farms will go for the agribusiness side. These will be tended not by tenants, but by absentees.

Such a farm takes in CO₂ (and some N₂) from outside, which is always higher-pressure than inside. When bees and humans need to use the farm, the bubble is drained of CO₂ and set to a high O₂:N₂ ratio.

On that topic some farms will need pollen. Mau Forest (Kenyan) bees will fly at 2.9km up. We do have Kenyans here to tend them.

Such a bubble will ride lower and hotter, in “spring”. In “summer” the bubble rises up to our 55km, and the bees return to hive. Excess O₂ (anything beyond what a bee needs) is removed from the bubble manually, as these plants grow. “Autumn”: excess CO₂ is scrubbed, sufficient O₂ added, humans enter. Cycle repeats. There is no “winter”.

SPLIT from 12 December, 2019.

Coffee in a donut

In the 50s° farming-latitudes over Venus, the floating terraced cities will need water and food. How about we give them coffee and a donut.

Yesterday I was thinking about the distribution of weight in a Landis spheroid. For that, we wish to focus the stress in as few places as possible, for maintainability. I had it tapering to the bottom, which is how I figured the habitations would be spiral-terraced. That well at the bottom is where the trash would accumulate - more so when it gets normal human plebs raising little kids. Which is what we want, somewhere at a self-sufficient planet. The inhabited surface area is a function of the radius. The people here need water, too, which has to be stored somewhere.

Meanwhile, for farms, we'd like to maximise surface-area. Also we don't wish that a single puncture drain away all the water at once. And I think we'd have to start with farming - at least, after visit-and-go missions.

To get internal density 1.3369 g/L, we want proportions of water at 1000 g/L against breathable air at 1.18 g/L - remembering that one displaces the other. I calculate 99.9843% air-volume. That makes for a small pool of water at the base of a sphere, and then we'd have to pump it back up the sides. Instead I recommend flooding strategic pools in a donut - a "torus".

The more total volume, again, the more water we get to carry.

In the hole of the water-bearing donut would be some central nexus, also a human-inhabited bubble: at least docking for aircraft, a market, an assembly, a cookery, and a clinic. The nexus lies snug between two nets, each attached at six points to the inner side of the donut.

Some of these tori will be given over to wildlife-preserves, starting at the desert level. These are popular for tourism. Savannah will be mooted later, for fatter rings.

It is not allowed to light fires in the torus. This whole setup should be designed to use as little electricity as possible. But over Venus heating and burning food is the least of problems.

The Empire State aerostat

In 2003, one Geoffrey Landis argued the case for Venus; here's PAT's copy at The Space Monitor in 2007. Landis also crunched (some) maths on how a colony there might look - it would float, using Earth's atmosphere as a lifting-gas. I'm taking this further.

Landis implied 50 km above the equator. Here, says he: A one-kilometer diameter spherical envelope will lift 700,000 tons (two Empire state buildings [ed. he means metric]). A two-kilometer diameter envelope would lift 6 million tons. He recommends the city be contained in this envelope. A half-kilometer radius sphere wraps 523,598,775 cubic metres. So he is claiming overall internal density 1/748 tonnes per cubic meter. That's the same unit as kg/L and gcm^-3. To work with it better: 1.3369 g/L. By contrast our breathable air is 1.18 g/L.

But it won't be evenly distributed. And Landis is not literally asking his Venereans to inhabit a sphere with a one-km (or two-km) equatorial platform bisecting it. A sphere rolls, and will tilt that platform. Also the platform would press upon the sides of the ball once an actual Empire State Building's worth of mass is planted on it. And it hardly makes the best use of the available outer wall.

I would suggest a sports-bleacher model. The inhabitants live, and farm, on terraces leading to a tapered bottom. That bottom is tied to Kindltot's anchoring kite-tether, to help keep this bubble from shaking. The terraces are grounded to the outer wall; which is stiffer and more resilient than the bubble walls containing the atmosphere above. The wall is also somewhat slick, but cleaning-robots can manage it.

Any trash that falls should (eventually) slide toward this well. It is the sector's responsibility to catch what trash it lets fall; those cleaning-robots will help in this. There is a final trap at the bottom of it all to catch what trash didn't get caught above. The general sector of the trash's source is marked so that the sector's cleaning efforts are audited.

An alternative shape for a floating city is the torus - the "donut". I take this shape more seriously, at least as predecessor.

Ion drives in orbit

Hollister “Hop” David: Ion engines really suck at climbing in and out of planetary gravity wells. The (weak) engine would not be moving its mass straight up or down, but spiraling. The values he gave for that snail-crawl were: 40 days to get up from Earth LEO (which is what, 400 km) to EM-L2; 20 days to get down from Mars/Sun L2 to Mars’ LEO (Phobos?). In support Hop links to this explanation on Stack Exchange.

Hop’s aim was to debunk Neil DG Tyson. Hop pointed out that, to get through Earth’s gravity well, a 2 mms^-2 thrust will condemn any human and most electronic passengers to a death sentence in the Van Allen Belts.

I am here for Venus, whose orbital range doesn’t have belts – but that doesn’t matter. Venus instead has direct solar radiation, and an induced trailing magnetosphere. These are just as bad for humans as Van Allen, as far as I know. I’ll assume most Venerean passengers don’t want to dink around for four weeks incrementally spinning to their planet’s desired altitude, either.

Some other schmo can do the maths for exactly how long it takes to get from X to Y over whatever planet, or for ion solutions generally. I am satisfied that the time is measured in weeks.

But I counter that slow-acceleration drives (like ion) do have a place traversing orbital altitudes: for raw-material low-priority heavy freight, which is still precious enough not to drop onto the Australian outback or to fire off into an eccentric solar orbit. It won't be foodstuffs. I'm thinking ores, phosphorous, and water. Also fragile goods we don't want to subject to sudden shifts in G.

UPDATE 8:30 PM - I don't know that ion drives will be used much o'er Venus. Venus has that impressive ionic coma of its own to give to its orbiting craft that level of thrust; as "NicoNicoNekomancer" has relayed it to me, the Electric Wind. Why buy an ion drive if you can just SAIL out there [UPDATE 2/8/2020 like with a Greason q-drive]. I might have to break down and do the maths, to make that call. But ion drives will certainly help over Earth and the Moon.

UPDATE 7/28: We have better ion drives than Hop knew about in 2016. SolVen-L2 can use 'em. THRUST 1/30/21: Ebrahami.

Proxima's other planet

Hat-tip to the Morning Report: Mario Damasso is reinforcing his position that Proxima Centauri has a second, colder planet – “c” (“a” being the star, by convention). “c” swings around on a circular orbit of about five to five and a half of our years. Its minimum mass is about five Earths but, since it doesn’t transit relative to us, is at an angle to us; so like to be rather heavier than that. The planet isn't visible directly; these readings come from seventeen years observing the star, alongside our increasingly-accurate measurements and understanding of said star.

Wikipedia as of this morning still considers Damasso’s conclusion “unconfirmed” but the evidence keeps stacking to his favour. The ESA’s Gaia mission is slated to release a dataset, the “EDR3”, later this summer. That might clinch the proper motion of the star and, thereby, nail down the planets’ angles relative to us.

For this weak-gravity star, such a long-period planet orbits only 1.5 AU away from it. Here, it doesn’t get much insolation. Damasso’s team projects 30-50 K temperature. That is the temperature of Pluto and Triton. I’d up that a bit, because I expect this one has an envelope of methane and of other such “ices” – read, gasses – to a light-absorbent extent, like Neptune. I don’t expect it to be visible to our eyes out here - ever. But there is hope for infrared.

At this distance, minimum-mass, and circular orbit; and since there’s nothing special between it and Proxima b: planet c has room for direct satellites and, in its L4 and L5, for Trojans - like Neptune's. Hildas too.

FLIPAROUND 12/24/22 - The outer c is busted by a method applied successfully elsewhere. Instead is confirmed an inner c, named d at the time.

How not to use your imagination

It was raining on Mongo one morning - so Jerry Pournelle heard from Emperor Ming’s court, which assembly cared nothing for the world outside. Let’s talk about a world where Ming is right. Let’s set up the idiot-mode for SF authors.

The monocosm planet is a panthalassa with small continents and a functioning tectonic dynamo. Also the landmasses, if in tropical zones, won’t feature high mountains.

Panthalassa’s small continents and islands, by sheer luck (or mischance), drift into some other latitude and dry out (or freeze – read on). This drift, periodically, slays most life on land. The desert-example looks like Bellerophon in Firefly episode “Trash”. Or maybe the tundra planet in Battlestar Galactica’s last episode. (There were only two seasons of that. SHUT UP SHUT UP SHUT UP)

Small-continent panthalassae are the “swamp world” when all relevant landmasses drift back into the rain zone. I’ll allow we can get ferns, mosses, and bugs to leave the seas there as here. As for jungle-(continent-)world, I’ll accept any reasonable explanation of how land plants evolved and survived past the tree-fern stage where imprisoned by the angry gods.

A panthalassa with only an Antarctica might as well be Hoth, as far as colonists care – note that Hoth supports a kind of polar-bear, likely having evolved by itself.

If we are looking to a world of craggy badlands, with oceans or not: in the tropics, these will trend to microclimates in each valley. Such are monocosm only geologically. So our lazy worldbuilder will not be thinking of Hawaii, northern New Zealand, or New Guinea. He will model his badland on SOUTHERN New Zealand and on Iceland, closer to monocosm - because they are cold and isolated. So this planet is probably a snowball too, elsewhere; and if not, it’s a young planet recently terraformed.

These worlds are uninteresting, aren’t as common as are snowballs or young Damocles-worlds, and as you can see here can even be redundant with snowballs. It takes a lot of work to justify (likely post facto) a lazily-designed planet – in fiction, as in life.

But these planets are out there; so once the interstellar network gets large enough, Planet Australia will hove into the viewscreen eventually.

Dying deserts

The habitable world-desert looks more difficult, given the difficulty the classic SF authors have had with it. For competent authors, that is also what makes them interesting.

Frank Herbert did propose an ecology for Dune, but his efforts there were (in the end) desultory, like CS Lewis admitting that for Out Of The Silent Planet he had done only as much worldbuilding as would convince himself. Both authors’ interests lay elsewhere. George Lucas did even less work for Tatooine (I’ll get to Hoth later): on his monocosm planets, he didn’t even ask if there exist an ocean elsewhere than in the (small) communities he detailed. They may well have oceans out of view. Blame the Expanded-Universe nerds for coming up with silly answers.

For a desert world to support oxygen implies it too has seas, but the continents are arranged such that little water falls on land. Start with the assumption of a land-dominated planet. Brian Aldiss mentioned such a world offhand in Helliconia Winter – “New Earth” or “Arabia Deserta Writ Large” (on Alpha Centauri C; we expect different of Proxima’s world now).

Now, here’s the problem: we have several examples of land-dominated planet close to home, and all have ended up with no surface liquids at all. I mean, except for Titan. Where the sun is so dim the liquids are ethane.

Land-dominated worlds aren’t tectonic; habitable worlds bask in hot sunshine. Put these together, and take away the Van Allen Belt: such worlds WILL die before their time - like Mars (sketched as Malacandra or Barsoom) or, worse, Venus. Even if they’ve kept a magnetic field, the water is still going to evaporate and blow off into space some day. Visiting comets and volcanism can resupply the water, but those events will be both erratic and catastrophic. For the small oceans and their shores: vast temporary flooding and changes to ocean chemistry.

Aldiss’ Ediacaran New-Earth, with its plants and worms, is doomed as Barsoom. And Edgar Rice Burroughs did it better.

In science-fiction, we can at least invoke an alien’s terraforming effort. I propose that this happened to Kharak in Homeworld’s backstory. I would propose that also for Tatooine; but Lucas’s third movie scotched that idea with the sarlacc, implicitly a native to this world.

Icebergs in a cosmic sea

The habitable ice planet is easiest to explain.

Authors on a time-budget may moot a “Snowball Earth”, on the model as has happened here on Earth. Here is a mostly-water world a few billion years old where has lately arisen a carbon-crashing but oxygenic cyanobacterium [UPDATE 2/15/24 OR: something removed the addition of carbon-dioxide, long after that]. Open water still exists; but it is equatorial, and littered with iceberg. It is not Hoth, since it supports no indigenous complex life; but it can be home. Maybe it will get warmer later; maybe there’s some other mechanism which prevents that. And don't expect much of a spinning magnetic core here.

The offworld habitable planets in Pohl’s first Gateway book are hinted as natural snowballs: Peggy’s World, and that other one. Also that miserable haven in the recent Battlestar Galactica series.

Book critics will complain that natural snowball planets are “boring” but they are also common, so will feature in any story set in an interstellar network of inhabited worlds. Pohl handled the phenomenon about as well as anyone could, by putting them into the background.

Cold planets are more interesting when unnaturally so. Such can happen in the aftermath of some cosmic accident - like Chicxulub. Expect these in systems as haven’t done with the Heavy Bombardment. As far as we know this event demands newly-assembled planets so precedes “blue green algae” by billions of years; but in science-fiction, we can allow that some alien (in which I include, humankind) has terraformed the 9.8g planet already and made it (prematurely) temperate.

Also expect cold snaps in the wake of war, once some attacker deliberately flings comets into someone else’s home.

These worlds might not be snowballs yet but they’re headed that way. They’ll get better later but not during the protagonists’ lifetime.

Monocosm

World builders often get criticized for single-biome planets – the Monocosm. The jungle planet, the swamp planet, the desert planet, the ice planet. . . All of these, “please avoid.”

For Monocosmatic planets right here, we got the subplanet Mars (desert) and the dwarf Pluto (ice). But Winchell Chung isn’t an idiot and knows all that. He would accuse me of cheating (not the first time a Houstoner’s heard as much…). His complaint is more against authors who have their avatars touch down on such a planet… and remove his helmet. Such planets cannot support complex life out in the nude. Not without good reason.

I notice that Chung leaves out “water planet”. Among extrasolar planets, several look like water-worlds with no land to breach its surface. I can well imagine a proto-Neptune drifting into Mars’ orbit before it got too big and gassy, here evolving a nitrogen / oxygen atmosphere over a 1.5 Earth-radius world-ocean. These CAN support life-as-we-know-it: James Trefil and Michael Summers, Imagined Life. It might be difficult for human life.

More to the point, we can stretch the definition of “monocosm” by such planets as are monocosmatic… as far as the explorer cares. It’s only the land that’s a monocosm. Oceans do exist. Everyone agrees to ignore them.

Theoretical physicists aren't doing physics

Sabine Hossenfelder believes that physics is stuck in a black hole.

We’ve let them spend billions of our dollars chasing empirical detection of well-theorised particles like the Top Quark and the Higgs Boson. I’ll grant the validity of the scientody. But frankly, these physicists could have waited. I ask, what of all this research can we use on Earth or in space. Better radiation shielding? Tunneling methods?

This is why I’ve been doing this series. I want that we reorient our scientists toward the lower-energy sciences of engineering and chemistry. The papers which Einstein published in 1905 were sufficient for that. Space, carbon-dioxide atmospheres, and gravity are sufficient challenges for our generation. In mathematics, I’d point to P ?= NP and Navier-Stokes existence.

At this point I’m up for challenging any physicist who tells us he’s working on particle-physics. “Why aren’t you putting your maths to work on turbulence,” I’d ask him. “And if you’re now doing ‘postempiric science’ then when are you applying for a move to your theology department.”

(In this blog’s context, that is not an insult; it is a serious question.)

Why wouldn't you?

Someone polled my erstwhile countrymen on whether they'd go to the Moon, and if not why not. Safety was guaranteed.

I've made some attempt to organise the reasons - to guess at why they came up with such reasons.

The most serious such complaints amounted to two. Four percent responded that the money would be better spent here. These are Communists. Nine percent denied that safety could be guaranteed. These are pedants, and at base a subset of the "scared" 5% and the fear-of-flying 5%. The Communists deserve some respect inasmuch as they've noted that somebody has to pay for it all. The pedants earn respect for calling out a poorly worded question.

I think that the 96% non-Marxists are awaiting an incentive before they'd consider space travel. Given the dangers, the expense, and the time: what would encourage people to visit another planet other than to carve "Kilroy wuz here" on a rock? And on Venus, which by the way takes longer to get to, most visitors won't even get down to the ground to do that.

This is why (for the Venus case) I put a premium on avoiding boredom.

Please don't recycle (here)

The slogan "what's so non-conservative about conservation" has been a concern-troll at least since Trudeau mooted it in the middle 1990s, there targeting the Gingrich House. Although if you spend much time thinking about life off Earth, you get to some sympathy with the sentiment.

It is turning out currently that our raw materials are getting so cheap that conservation is becoming a money-loser. Tierney over at Instapundit's blog notes that the NYT (no less) was saying "recycling is garbage" in, yes, 1996.

The answer is to research ways to make recycling work, and not just as another smarmy signal of personal virtue against one's neighbours. Until then we're going to need to make landfills work.

Consumer-report on a Licerion battery over Venus

My aeroplane for co-efficients has 0.5 lift (c_L) and 0.015 drag (c_D). It runs 70 km over Venus where the air-density (ρ) is 0.09 and the wind-speed (v) 100 ms^-1. Given that, it must discharge 675 watts per square meter of wing, to its turbine. I have already ascertained that 20%-efficient solar is NOT a cruising-altitude power-source at this pace. Solar does work at half that speed... until the plane goes into night. At that point the plane needs an on-board power source. So let's talk about rechargeable batteries.

Assume four days out of external power. For stored energy, that needs 64800 watt-hours times the wing-area. Eventually I want to bring a telescope, so I demand to stay over the vitriolic clouds where ρ=0.09. Besides I don't want my plane to dissolve when I'm in it.

Sion Power (after abandoning Lithium Sulphur) are promoting a "Licerion" promising 650 Wh/kg and 1400 Wh/L (pdf). That is mass density 2.15 kg/L; the same unit as gcm^-3... or tonnes per cubic metre. It compares well with a hunk of light silicate rock.

To pick the one emerging technology I could find which published comparable data: IBM "seawater" offered minimum 800 Wh/L energy density. Also 10000 W/L power density, 90% efficiency, max 300 s to 80% charge. I assume it's about as dense as Sion's.

At 100 ms^-1 up here Licerion would add 100 kg per cubic meter of wing: 864 Newtons / m². It takes up 46 cubic meters of space which can distribute among the wings. Double that if we're allowing eight days.

1/2 ρ v² = 450. To hold up 864 Nm^-2, is needed c_L * 450 Nm^-2. The lift coefficient must surpass 1. LOL! Fortunately I'm plugged into the Flotilla so I don't care.

At 50 ms^-1, 1/2 ρ v² = 112.5. I'm fighting much less drag: at a 0.015 drag coeff, 2.53 Nm^-2. About 50 Wm^-2 would power through that. (By the way, IBM's power-density would allow 200 m² wing... per liter of battery. Or 200000 per cubic meter. I am most NON-worried about power density here. And wait 'till we introduce capacitors.)

This battery, four days out, has used 4860 Wh / m², only requiring 7.48 kg / m² = 64.8 Nm^-2. This minimum lift co-efficient is 0.576.

When we add the mass of the turbine and the equipment, Licerion alone cannot lift a 0.5 c_L, 0.015 c_D aeroplane at 70 km over Venus for four days. But it comes close. For instance Licerion can easily power my vessel for TWO days, with cargo. Licerion is already enough for an untethered plane to enter distress-mode: by which I understand, one or two days drifting back before some rescue-tug rides in for a rescue.

For our plane we're looking not to exceed 5.19 kg / m² = 45 Nm^-2. To overcome 4860 Wh / m² drag: a 936 Wh/kg battery would do it. If we had, oh, 1000 Wh/kg: we could easily squeeze four days from this vessel, and have mass to spare to carry actual freight.

Unlike with 50+% efficient solar-cells I do not consider a 1000 Wh/kg rechargeable power-source to be unobtainium.

ALPHA 1/26 - hang on a moment. Given that IBM is claiming for the seawater battery, a power density of 10 kW/L: if we assume density density of 2.15 kg/L... that's a specific-mass value. α = 0.215 kg/kW.

The car-batteries of the near future

For those wondering about power during whatever timespan the solarpanels aren't doing their thing, the Pocket-Lint site has a summary of some 2014-19 research on "batteries". By "batteries" we should understand arrays of whatever stores kilowatthours and rations back watts at a steady rate. And we're expecting to REcharge them. This means chemical electrodes and capacitors.

I expect my Venus-region batteries degrade slowly (on par with aeroplane-maint'), are light weight, recharge at a reasonably fast rate, and are cheap to make in space or in low-pressure CO₂ or in an acid bath. For my aeroplane turbines I also want them to perform in high temperatures (electric car batteries demand 60 C), and to discharge VERY fast on demand. We don't care about flammability in oxygen where there is no oxygen.

This does rule out the "Air Battery", like aluminium and zinc... until we get a CO₂-burning version, in which case we'll need them not to explode too.

A power cell provides energy when ions move from the negative anode to the positive cathode; when the cell recharges, the ions move back. For the ions: lithium, the lightest metal (except hydrogen) and also reactive, is the standard choice. In Pocket-Lint's article, battery management and temperature modulation segments assume lithium.

Some of the research is to get more lithium in the right place, without exploding. The present standard is LiC₆. Lithium-sulphur is over-hyped. We are also witness to grand promises about All-solid-state... but at least the producers admit it. Dual Carbon was another lithium tech hyped in 2014; but I don't know what has come of that. A present serious alternative is Li₁₅Si₄.

For non-lithium solutions IBM is talking "seawater". That means brine, to chemists. Besides the obvious saltwater, brine is mined for magnesium, potassium, and bromine; when people talk seawater in this context, they often mean magnesium. Sodium is also mooted (UPDATES June 2020, December).

Another option (for a moving vehicle) is the capacitor. These charge and discharge (much) faster than do chemical powercells. You would just need a LOT of them - they'd be used alongside the solar panels and chemical cells.

Or, you could use graphene in your anodes and have a capacitor-cell hybrid. UPDATE 1/2/2021: Post-graphite is good for sodium too.

The flotilla's warehouse

Just because we have a permanent flotilla (11 AM or not) doesn't mean we have to be dragging all its mass, all the time. When not needed, some components are allowed to drift into nightside: I've mentioned astronomy, aeroplanes in distress, and simple commuters. Solar is sufficient for these. Also, many visitors and incoming trade-goods are destined for the floating farms in the 50s°.

Some dead weight which the flotilla carries cannot be so easily distributed to the night-drifting vessels. I am mainly thinking of the outgoing rockets, and whatever heavy materiel they are shipping up in quantity. Junked aeroplanes, spent nuclear fuel, and bad solar-panels all have to go somewhere, too. Not to mention basic maintenance. All of it is heavy and bulky, and no other Venereans want it, and the flotilla can't use it and isn't ready to send it on just yet.

So: floating set of warehouses, at the equator. Since they ride low in these clouds, they are bathed in acid near boiling-point. Heavy industry is also possible here - so here is where stuff gets fixed. (The solarpanels, once sorted and reassembled, might end up going back up to lower pascals.) And Venus A & M University is here to feed it.

I dare say that this is where the flotilla is first built at all.

The first Venus investors

I have limited the Unobtainium required to install a self-sufficient Venus colony. It relies upon several components working together: including a mountain kingdom (i.e., a Bond Villain Lair) and a 50 km unsnappable chain. All that, requires investors. These investors currently live on Earth. I don't assume they be immoderately villainous, but they will like to get paid after a few Venus-Conjunction synods.

We need a first mission to Venus proper that might offer a short(ish)-term Return On Investment.

That would start with the Venus-crossing asteroids, starting with coörbitals. The prerequisite would be mining operations on Earth-crossers and coörbitals, and certainly an Earth-orbiting refining base - the L4 and L5 points fore and aft our own Moon look like winners (thanks Hop David).

First, we sic some miners onto one of those Venus-bound orbiting rocks. Wikipedia led me to 2013 ND15, which lists also as of 2014: 2001 CK32, 2002 VE68, 2012 XE133.

2001 CK32 (19) and 2002 VE68 (20.6) are the high-magnitude ones, which is how they were known as the only ones for a decade. They'd be the whales, that investors would start with. If 0.2 albedo is assumed the estimator calculates 470 m mean diameter for 2001 CK32, and 236 m for 2002 VE68 - that is, visible area 1475 m² and 740 m², as seen when it's tumbling. By contrast the Saturn V cylinder at 10 x 110 m had a visible area of 1100 m² if seen side-on, more like 32 m² if seen front-on.

Most useful for any electronics and even humans at an inner-system asteroid, would be the stone, to protect from the radiation involved in a Mercury-crossing orbit. So I suggest 2001 CK32 first. This mission will need to bring its own refinery, solar panels, and 3D printers; and some means to catch the sun's escaping ions. I expect it will be an Earth-region space base simply moved into this new orbit, to dock with the rock.

The stone, I think, will contain some oxygen; and especially in the "Sunshine" peak there is an opportunity to catch solar hydrogen and helium ions. Energy will be solar: Venus gets insolation 2620 Wm^-2. Oxygen and hydrogen, of course, make up water; also simple propellant. Also during this time, the rock is repurposed to shield the habitat and important electronics. Over the rest of the 583-4 day synodic, sufficient propellant should be collected for a return to Earth on Hohmann.

Those on schedule to go home: helium, other precious metals they won't need over Venus, and workers who've done with their shift and also want paid. A reusable craft should have been sent four weeks ago with their resupply and replacements; that first crew can return with a clear conscience, if they leave sufficient propellant behind them.

When the rarer-earths are fished out, for any given 'stroid, the now-shielded original craft moves into the orbit crossing Venus' ionic coma: oxygen, hydrogen, helium. I recommend L2 for protection. These components are assembled there into larger and more-efficient stations that can (re)capture those ions - which isn't done in L2, that's done over Venus proper. The rock is also sent over and reassembled, to be combined into an even bigger stone shield for humans who DON'T want to be bathing in ions. Smaller rocks like 2013 ND15 and 2012 XE133 and probably 2002 VE68 too might as well just get cracked into bits where they're at, and have their pieces pushed over to Venus by robot to be worked in orbit.

Voilà. A Venus orbital station. These four asteroids - and whatever else might traipse in on a Venus-crossing trajectory - should be able to supply a few decent-sized, shielded, and 8.66 g habitats over Venus for awhile. I'd set a permanent darkside icedepot in Venus' umbra.

Some can move on to supply more-stable L4 and L5 stations... and, in the meantime, to pay the Earthers. These stations, therefore, exist first as energy-cheap refineries for Venus-crossing asteroids (just like their models back home!), and for helium catchment.

Over a few synodic years, we will see the first Venus-based investors. They'll be the ones looking at the great chemical-factory that is Venus' low cloud-bank. That's where "ISRU" kicks in. And thence to Maxwell Montes and long-term farming communities.

Ishtar Terra is a harsh mistress

On 14 December around 11 AM I started an ecocycle for Venus' colonies. I am bumping this to this morning to include the steps I've added this week.

The whole Maxwell / Lakshmi system at 65° ecliptic-north offers all manner of ores, including phosphates and sodium hydroxide. Wherever we post our mining-base, it also sabatiers water and oxygen from cloud-vitriol, and distills heavy-water. It tethers an escalator to 40 km-ish at the low edge of the clouds. That port refines the phosphates and other ores, and packages these and the heavy-water... into an aeroplane.

That 'plane flies its cargo on to a Uranium City in the same altitude (every four Earth days, being a wind-day). Uranium City at the 50s° does more refining, particularly for Uranium Hexafluoride, and feeds its own reactor - dumping the waste somewhere on the vast basalt wastes of the planet. Above that are floating farms: that city gets energy, and light water, and the fertilising chemicals and minerals.

The city grows food: in "food", I include all organic consumables, like paper and wood and (with the lye) soap. Excess food goes back down to the Uranium City. The Uranium City flies its own excess food over to the tethered port over the mine. The port takes a nibble and slides the rest down to the mine - along with vitriol, and other chemical byproducts it's produced.

55°-65° ecliptic north, spanning the Polar Collar, supports a trade-cycle that keeps everyone in it fed and supplied. From thence, I have found more expensive to get to the equator and up into orbit.

The rest of the System still needs raw material. Last month I allowed the Venus day platform being served more from the southern farms. For mines, it might use the higher points of Aphrodite Terra at the equator. South of Aphrodite I see little that rises about the supercritical-CO₂ "sea level" at 3 km. At first, though, Venus orbit will invest in the 55°-65° north band and exact payments in ores.

I can see the whole Ishtar network becoming comfortably interdependent together, and increasingly independent of the rest of the System. A Terra-Nova, de facto.

Girdler

One-neutron hydrogen, "deuterium", is vital to nuclear-energy generation in and over Venus, and elsewhere. Venus starts with ²H proportion: 0.016. This is considered a high proportion, as solar-system atmospheres go; but I'd not pump this mix into a reactor.

Over Venus, most water and hydrogen-bearing compounds float in the cloud-layer. Here we get the Girdler sulfide process for free. Said process is cost-effective similarly for the surface mines, as a byproduct of their air-conditioning and water imports. In any place, the Girdler process boosts that ²H ratio to 0.15-.20. Still not good enough by itself, but at least at the point a distillery can sort the rest out.

Girdler works with two sieve tray columns. One column works at 300 K, uncomfortably warm to us but well-within the tropical range of Venus’ 50s° latitudes; and the other at 400 K, the conditions surrounding Venerean industrial cities, which I'm hanging low. That the hot tower sits below is frequent for Girdler mills on Earth. They'd be tethered together; aerofoils (kites!) should do it.

Every city will keep the light water. The floating farms, for their part, sell the heavy(er). I haven’t considered who distills the floaters’ heavy water; I assume a central distillery.

Uranium city

The greatest need of the permanent flotilla – and a need for all the solar-system – is energy. Some of it is solar, especially close to the Sun - like dayside Venus. But solar is not always enough. Plan B, then: nuclear fuel.

Start with the fuel itself. Wherever the ore comes from; we must refine it, and reprocess it. That takes a centrifuge. You may remember such from the news where they're talking Iran. The material I've chosen is Uranium-235; but we can analogise from here to any other separation-process that involves high temperature, high pressure, high energy, dangerous chemicals, and toxic waste. All the stuff you'd rather have done on another planet.

Uranium-hexafluoride has a “triple-point” from 340-500 K. Over Venus a bubble can reach the low-end of this (high) temperature - assuming the mid latitudes - from up to 50 km altitude, the lower range of where these latitudes hit pressure of one bar (pdf); down to where (by coincidence) tin melts, at 30 km altitude. All below the cloud deck but still in the haze. UPDATE 7/24: We have tech for that 40 km up and, since air isn't liquid, our design can be more uniform per vertical level. UPDATE 8/9: We can recapture waste energy here; unlike that 900 tonne submarine-reactor. So: helicopter-assisted?

This bubble is untethered, so drifts over the surface. This way the bubble can jettison depleted-UF₆ and other wastes onto the low parts of said surface, and not mess up the environs of such surface mines as I expect for the highlands.

For the centrifuge, this bubble (city) uses its own power supply – and, since solar and wind power are insufficient down here, that supply is itself nuclear. That extra heat would also pull water (as steam) from the ambient acids directly, without a Sabatier; and it sterilizes the “grey water” from the crew.

The city takes in spent uranium, for reprocess. And replacement parts.

The most important (and first) industrial low-floater floats over the equator; that's mainly a warehouse, for the flotilla. This further can take advantage of the upwelling Hadley air although it's not very strong (D Crisp, "Radiative forcing of the Venus mesosphere" #2, Icarus 77, 1989: 0.015 m/s).

As to the water, the Girdler sulfide process exists between this factory and whatever is above, to grab some of that Deuterium. Normally the hot tower could ride further below but we have extra heat here. That 15%-20% H-2 water is exported, along with excess U-235.

These bubbles drift like the farm bubbles. I'd suggest the industrial bubble and a farm bubble float in tandem but this might be a waste of energy over the long term. Also semipermanently tethering the low-altitude powerplants with mid-altitude farms across, what, 20km seems dangerous. I think each balloon handles its own watermaking from the acid, and does the best it can generating its own electricity. Every few days the low bubbles and high bubbles resync, and they can trade.

The productive farms will be in the 50s° latitudes: where the weather is nicer, the industrial bubble can change its farm as needed, phosphates can come up from the mines, and the bubbles can (probably) float closer together. In early days the Aphrodite Terra farm is nonideal but good for practice in extreme conditions. That one later will become a university.

Fluorapatite

Yesterday Venus got in the news for the chemical composition of its surface. Let's follow up today with the most valuable mineral on that planet: Fluorapatite. This is where the farms get phosphorous. No phosphorous, no farm. No farm, no food. No food... no investors.

People tell me the clouds might bear some phosphoric anhydride but if so, not in any useful quantity. I am afraid this is going to have to come up from below. Herewith I invoke The Law Of Boldface : Prospecting for fluorapatite or at least apatite is the highest priority for a Venus colony. I'd look seriously at the western "paterae" of the Lakshmi Planum - although, before we dig into those volcanoes directly(!), I'd first check if they deposit their treasures for us, on the side of Maxwell to their east.

Wherever there is fluorapatite, there is a Sabatier on the ground to serve its miners, and a flying tethered port above. That port exposes powdered fluorapatite to the outside. This process retrieves calcium sulfate, hydrogen fluoride (in the form of concentrated acid), and phosphoric acid.

Most exports go on to the floating cities, but they do use the hydrofluoric acid back down in the mine.

Note that “calcium sulfate” here includes all the solid impurities of this ore, of which uranium is the most precious.

Life in a weighted balloon

Whether hauling a centrifuge below the farmlands or a rocket below the flotilla, or riding the currents above Maxwell Montes: I've now got a human colony deep down in the vitriol cloudbank, much lower, darker, denser, and hotter than a Mamean farmer should like. This habitat needs extra protection from acid, and extra buoyancy.

Humans will here need protection from the air-pressure. At 40 km over the surface that's already 3 bar, like the Cousteau submarine base. Below the haze at 30 km, we're looking at, what, 8 bar like 80m below our own ocean's surface - more like a nuclear submarine. Humans - and, at a certain depth, electronics - also need air-conditioning. And half the year they're not growing their own food anymore than is the Forever Flotilla (which has a premium on space and cannot count on forever sunlight).

On the (relatively) bright side: the people here (like down in the Maxwell mine) enjoy all the fresh water they can drink and shower with, knowing that the "grey water" can just be sent to the low-altitude reactions which will run pure water as steam, right back home for condensation. Whatever non-water waste they generate can be exposed to the outside where Venus will sterilise it.

Among what the low bubbles all have for trade is excess water, light or heavy. If the low bubble is feeling independently-minded, it has pure hydrogen in its light form; that can go into balloons, to sell goods on the side. Those balloons with the low-colony's Less Official exports might have beacons so that the buyer can retrieve them with acid-protected drones.

Ishtar's installation serves cloudcities at 50-5 km up. Aphrodite's warehouse will serve the flying port at 70 km.

Maxwellport

For my first trick I'll anchor the Sabatier reactor on one of Venus' Terra continents.

Artificial spires reaching up to the clouds have been mooted. On 12 November last year, I stumbled across Multiplanetary Society: A New Approach to Terraforming Venus (March 2018) - second hand. The Maxwell range is certainly the best anchor-point for such. But before we all go full Cheops, I'm recommending a flying set of chains as more practical. Resisting the wind rather than drifting in it...

If the lower installation is anchored onto some Terra firma, it can run a full set of cables all the 45 km up to the cloud-bank. Each cable is kept aloft in this thick, ever-moving atmosphere not just by balloon, but by aerofoil kites. I don't know what the mass of the cable needs to be, but I do know that aerofoils work great over this planet at providing lift for free, as does superheated hydrogen. In this case the cables need to concern more about horizontal shear (drag) than about vertical gravity - which should be less, and distributed evenly per segment of cable.

Usually people talk up Muh Kevlar (UPDATE 15 Sept: now, T1100G) for very long cables but for the lower altitudes, I'll go with the heavier, but 42,000 kgms/sq.cm, steel wire. Higher up I need acidproof polymer or alloy. The mine’s tethered port doesn’t run tethers any higher than 45 km; it’s already pushing its luck.

This Sabatier setup is first tested from a shed outside and below the Maxwell Montes mine. That mountain is already the highest point above the supercritical "sea level", and at its para-arctic latitude I believe that the condensed clouds will be lower. It also, one hopes, will host a colony in need of water and oxygen, and with the ability to get out and fix the reactor should it corrode and/or overheat. And if the cloud-cities at the 50s° latitudes are dragging their own tethers; theirs won't tangle with this one's, rising up in the mid 60s°.

Some of this water, being hot, can get piped right into the Maxwell colony, to collect up in that cistern. Certainly the rest of the colony will appreciate the oxygen.

The mines, with access to so much free heat, distill their own heavy-water (after Girdler) and export more of it all the way to the flotilla. I don’t know if they import additional 15-20% ²H water for reprocessing; other cities might do their own distillations too.

To shuttle people up-tether, we'll need strong life-support. For comparison our submarines operate 300-450 m underwater, so 30-45 bar... which Venus hits from 15 km up. Between the floating or flying cities (yea, even unto that fountain, upwind), and this tethered outpost: aeroplanes should get the job done.

The tethered balloon-port above it - if so - will be that site whereby Maxwell exports its ores. I hear there's a demand for nickel.

A wellspring at 45 km altitude

Venus is generally dry. Its cloudcities and the flying port want water. The flying city may rely on the stations to drop it here. But the cloud layer already has some water, and more hydrogen and oxygen bound up with the sulfuric acid. Let's get at it.

Zubrin was big on better living through chemistry - on Mars. Once he'd pressured enough carbon dioxide into one Earth atmo, added some catalyst like nickel (if, as he snarked, you are cheap) and heated it to 300 Centigrade (573 K): Zubrin could run hydrogen though it, and get water and methane back. This is the Paul Sabatier reaction. The reaction was exothermic too so the energy could be used elsewhere - like in splitting the water, to retrieve the hydrogen for oxygen.

Sabatier remains in active research, mainly looking for lower-temperature catalysts. For this planet I have in mind a different engineering scheme.

Venus can run Sabatier for, almost literally, the cost of a nickel.

The Kelvin hits 573 K from 21 km on down. The atmosphere here is 21 bars higher than Earth's, most of that being the carbon-dioxide we're making use of. (Yeon Joo Lee's thesis pdf). Not only that, but the methane starts undergoing pyrolysis - if you drop the methane 'waste' further down, you will get some hydrogen back, again, for free; and carbon soot. We do have to worry about electronics melting: tin, for one, liquifies at 505 K.

Plant cellulose can be returned to water and carbon soot, and perhaps phosphorous ash, simply by grinding into powder and exposing it to the outdoors at the higher pressures below.

Now, what about all that soot. This can be recycled for whatever else, maybe graphite or diamond. Or: lower the soot and some captured sulfuric acid to that 20ish km level, until the vitriol breaks back into sulfur dioxide and water (and into CO₂, which you just vent). I prefer to use carbon-dust for that because, although vitriol has its own pyrolysis: that occurs at 830 C, hotter even than the surface.

So here's a proposal for another chain in Venus' colonies.

This colony's basis rides over, or on, Aphrodite or Ishtar. Such bears enough air-conditioning to keep the liquids, liquid; and to chill whatever electronics need protecting from Venus' metal-melting environs. It also has our nickel-dust catalyst, which won't melt - and we'll take measures that it won't corrode, neither. The site can be on the surface (3 km, in Aphrodite); or tethered to cables 15 km above - which would help with the A/C at the cost of being a bit more shaky. What this tier doesn't have, is humans.

This remote-controlled reactor is in contact with an air-conditioned balloon, or series thereof, in the cloud bank - riding where the pressure (about two-bar) and temperature allow pure water to condense. The top balloons are there first to catch sulfuric acid, and to drop it to the reactor. Don't worry: we'll get to, "how".

The lower establishment periodically sucks the carbon-dioxide from outside and runs hydrogen at it - voilà, Sabatier. The methane is kept in place in this temperature and allowed to break into carbon-soot and back to hydrogen. The heated water-vapour rises back up to a balloon. It is assuredly a rising gas at this temperature and pressure.

You'll notice that we've lost some hydrogen to water. For replenishment, and for any requests for additional hydrogen, we crack the vitriol from above. The cooled acid is drained into the high-temperature soot, which then goes to break the vitriol back to sulfur-dioxide and water (and CO₂ again). Some of that water is broken down by electrolysis. The sulfur-dioxide is simply vented. The carbon-dioxide may as well be vented too. The oxygen from the electrolysis gets stored in a decidedly separate balloon - we don't want a Hindenberg down here.

Now to connect the cloud to the reactor. I suggest cables - multiple chains of cable: each with its own alternating balloons, and intermittently interlinked. Several materials support a chain over dozens of kilometers (Kevlar is the nerds' preference but... it dissolves in acid). If one link breaks, it can be fixed. They are how thermoses of chilled vitriol get down to the reactor; and how balloons of water and (where needed) methane, carbon, oxygen, and hydrogen rise back to the top. The cables can also carry fiber-optics for mutual communications. And robot avatars in case something needs fixing - we will, of course, have to yank the robots themselves down or up for repairs when done. (I'd earlier considered plain ol' tubes, but I ruled keeping those leak-free in these conditions a clear Unobtainium. I don't think fiber-optics have the same problem.)

How do we keep this vast chain airborne? I don't like the energy-cost of dragging 60 km of all this below the permanent flotilla, so we'll rule that out. And they'd be a dead weight on a cloud-city as well (although maybe we can use hydrogen balloons, especially further down, and can live with the city floating lower in the clouds). The rest'll hold for the sequel.

Pettit's handwave

Proxima's planet, as Earth sees how it redshifts and blueshifts its star, is 1.3 our mass. And since its visible orbit is not a transit, that 1.3 is a minimum; the thing could be rolling along at an angle to us. If you land humans on Proxima's planet, they will struggle to get off again. Worse than we did from Earth.

Don Pettit (pardon the misspelt URL) did the Tsiolkovsky equations (like a sucker), where m_init = 1 and m_final = 0.04.... or claimed he did. Pettit concluded that a planet 1.5 times the diameter(!) of ours could not get a rocket out of the gravitational well. How did he get here?

Proxima is a decent proxy for that hypothetic Big Earth. We can agree that a solid planet heavier than Earth should be larger as well (and that a less-dense planet, like Venus let alone an ice/water world, will be). We can agree that this star is likely forcing Mercury-slow rotation upon a planet so close, such as not to be forcing an oblate shape. We can also agree that the atmosphere on Proxima is unlikely to be Venus-thick nor consistently Venus-fast: so we cannot count on a high-flying spaceport. I don't know about equatorial mountains, but we can agree to neglect them. Sea-level G is the G what Proxima's planet gives us.

m_final is, of course, the payload's ratio so the highest Pettit allowed with a chemical rocket (nuclear might allow higher m_final). ln(m_inf / m_final) comes to 3.219 - as minimum (nuclear m_final may yield lower ratio, here). So delta V >= 3.219 exhaust V depending on the rocket's efficiency.

My next challenge was how Pettit's maths got him to radius being the magic quantity; rather than, oh, mass. Stack Exchange scratched its head too.

But eventually I realized - Pettit is talking escape V, and has swapped escape V for a function of surface-gravity and radius. He maintains 9.8 g to allow his alt-Earthers a humanlike form. Pettit assumes his larger (and heavier) planet is less dense than 5260 kgm^-3. To be exact, his Big Earth is 3624 kgm^-3: which looks to me barely more than pure rock and charcoal density under internal gravitational pressure. Let's pretend that Proxima's inner planets are indeed this iron-poor. (A thick layer of ice and/or water over a denser core would also do it, if we weren't talking Proxima.) Maybe the titanium for the rockets drop in from an interstellar comet. BUT ANYWAY

So the delta V = Math.Sqrt(2g) * Math.Sqrt(R), also a minimum; it is this which must >= 3.219 exhaust V. Assuming g stays 9.8 on prairie, adding planetary radius does indeed add to the escape velocity. So: exhaust V <= 6.093 * root(radius). Backtracking from 9680 km, Pettit refuses exhaust-V above 18957 ms-1. I'm not bothering with the maths anymore; maximum specific impulse horizontally would be 18957 / 9.807 = 1933 seconds, but our rocket is going up and trimming g down. Perhaps there exists no singlestage propellant to accelerate to that speed before the gas runs out.

The Stackers first noted that multiple stage rockets could surmount this. Also, the consensus arrived that Pettit's whole exercise is moot. Nobody serious cares about leaving the well on the first go. They just want into orbit.

Once in orbit (Proxima's inner planet probably doesn't have its own moon) Prox-Simians are Halfway To Anywhere, and can start assembling a depot. (Assuming they haven't already inherited one from the first colonists.) The planet can meanwhile use planetside mass-drivers to fling nonfragile materiel up there - starting with the fuel needed to get back down. The escape velocity from that orbital depot is what matters now.

So Pettit was wrong, and Ross Pomeroy did not follow the math. Pomeroy needs to do more of that if he's pretending to be a journalist on this field. As for Pettit, he needs to show his work better.