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# Department of Science, Math, & Technology

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What conditions would support permanent human settlements?
Posted: Posted October 3rd, 2015 by chiarizio
There are 8 Replies

How likely is it that a permanent human settlement, in which children could be conceived, born, brought up, educated, live and work, meet mates, pair-bond, and have and rear children of their own, could occur on worlds whose gravity was:

NASA says 2G or 3G is about the upper limit, but would obviously require time for acclimation. Ordinary colonists might do better at a maximum of 1G to 1.5G. Reducing the gravity much below 1G and you start having problems with muscle mass & bone density. This is fine for a trained astronout on a several month mission in a space station after which he's going to come back to Earth. People moving to & being born on another planet is a different matter, I would think.

How likely is it that a permanent human settlement, ….(etc.)…., could occur on worlds whose ambient atmospheric pressure on the surface was:

Sea level atm pressure is about 750mmHg and up in Boulder the average is around 600 and in Quito 530ish and in La Rinconada (highest city in the world) maybe 425ish. 425mmHg is about 57% of the sea level pressure -- but people are obviously able to be born, live, mate and die up there without any difficulty. Drop a bunch of people used to sea level pressure on a planet whose sea level pressure is 425mmHg and they might have some difficulties! I think 2 atmospheres is probably about the most you'd want for ordinary colonists to have to deal with. (Divers and pilots obviously deal with much higher pressures, but they have special equipment and breathing mixtures that are incompatible with several of the activities you mention.

Assuming the most comfortable temperatures for humans on Earth are between 68F and 77F, that is, between 20C and 25C, that is, between 293K and 298K:
How likely is it that a permanent human settlement, ….(etc.)…., could occur on worlds whose ambient temperature on the surface was:

Temperature and humidity are much easier to control with technology (airconditioners, dehumidifiers, etc) while leaving people to go about dressed more or less as required by the environment. Obviously, people live entirely low-tech lives in bitter cold places like Siberia and Nunavut, with appropriate clothing and shelter.

Oymyakon RU typically gets down to -60F in winter, but people just bundle up and burn all kinds of fossil fuels to keep out the chill! Get much past 130F with any kind of humidity and humans just can't survive the heat without help. There are certainly places where people have built up low tech civilisations in areas that get pretty toasty in the summer.

We could ask similar questions, I suppose, about the scarcity or abundance of oxygen, the scarcity or abundance of water, and the scarcity and abundance of NaCl.

We definitely need water and minerals. Oxygen is also a good thing.

Way up there in La Rinconada, the air is perhaps 12 or 15% oxygen, as opposed to sea level 21%. Again, people get along well making babies and working and so forth under those conditions. Principal industry up there is gold mining -- pretty heavy labor!

Appropriate clothing, sun glasses for all, sufficient indoor environment for ordinary activities to take place and UV exposure is minimised.

99% Earth levels and 101% Earth levels,
90% Earth levels and 110% Earth levels,
50% Earth levels and 200% Earth levels,
10% Earth levels and 1000% Earth levels.

I think as we can see, some of the parameters are more central than others. Some have easy low-tech fixes while others simply can not be surmounted by the human body. Also, take into account that the people you wish to be subjected to these differences are ordinary folks -- teachers, children, technicians, cooks, cleaners and so forth. Colonists in other words, as opposed to highly trained climbers or deep sea divers or what have you.

I think a good rule of thumb would be, for a person to live happily in an exoplanetary colony situation, the colony planet ought to be a very close match for Earth.

Out of all of these, I think temperature and pressure are probably the most forgiving, since we already know we can survive wide swings in both at minimal technological assistance. Oxygen levels are much less forgiving; water is also much less forgiving.

In the case of temperature, 99% and 101% are accomplished nearly every year by people living in temperate zones; and 90% is accomplished in the depths of winter by folks at latitudes 45 degrees and higher, while 110% is accomplished by, for instance, residents of Death Valley at the height of summer; while 50% and 200% probably would require special technology that would be expensive enough a permanent settlement would probably be unlikely, I guess, at least at the moment; 10% is almost cold enough to liquefy some atmospheric gases, and 1000% is almost as hot as the surface of the Sun.

Right. The farther afield you stray from "Earth normal" (for any given definition of "normal" here on Earth!) the less likely a permanent colony will be where people will be expected to live normal lives and have children who will grow up to be extraterrestrial humans. I think if you need to stray, try to pick one or at most two of your parameters that we know humans can live in and thrive in without all the high cost technology and work from there.

All that said, questions you didn't ask about are ones of local life forms and in particular those of the microbial sort. I would hazard the guess that if a planet harbours microbes that are common and deadly to humans, we won't be stopping long!

Weather is another question that might be of interest to consider: a world aswirl with massive hurricanes for most of the year might not be an ideal colony world; or one that is seismically extremely active. Mind you, those could be interesting starters for a colony story -- a seemingly innocuous planet is colonised, people left more or less on their own, periodic swings in violent weather or seismic activity level the colony's technolgy, leaving the people to survive your not-quite-Earth with little more than their native capacity to adapt and survive. What will they be like fifty or a hundred years on when outside communications arrives again?

Posted October 4th, 2015 by elemtilas
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Thank you, Elemtilas.
It looks like, in general, 99% to 101% Earth normal is probably just fine; 90% and 110% can be accomplished low-tech by "extremophile" humans; 50% and 200% are near the limits that humans can survive long-term, and in some cases require technology that would get in the way of, for instance, begetting and conceiving and bearing and rearing children; and 10% and 1000% are outside the range of survivability for humans.

Suppose a group of space-colonists landed, accidentally prematurely, on an alternate-Earth (without humans) near the area where the alt.Europe and alt.Asia and alt.Africa all come together, in the equivalent of an Eemian period. Now suppose everything after that happens ten times as fast as *here* on Consensus-Reality Earth in Our Time Line. There's an Ice Age, and a Toba-Disaster-equivalent; what order they come in I don't know. Then the Ice Age ends, then there's a Younger-Dryas-equivalent, and so on.

Would the combination of an Ice Age and an alt.Toba-Disaster wipe out their technology, setting them back, essentially, to (some equivalent of) the Scientific Revolution and/or (some equivalent of) the Enlightenment?

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The reason I suggest they land prematurely is that, with the sea levels and greenery being different, they might not quickly recognize the planet as alt.Earth (even if they came from future.real.Earth) at a first look, if it were in an alt.Eemian period. So I wouldn't want them to have time to study it closely or with advanced techniques.

Let's also assume they don't recognize the Moon. (But they'll notice there's just one satellite, and, at the first solar eclipse, they'll notice it's just about exactly the size of the RealLife.Moon.)

And, once they have telescopes as good as Galileo Galilei's, they'll be able to see Saturn's rings (maybe they won't have to wait that long?), which also ought to make them suspicious.

I'm assuming they'll lose the ability to make new records of the high-tech type they came with, or copy existing high-tech records, or search high-tech records by any means other than just reading through everything. But I'd like an in-story explanation of how and why that happened. What satisfies Occam's Razor better -- they crashed and all that equipment was irreparably damaged in the crash, or, they were caught by surprise by a flood or a freeze or a volcanic eruption, and that's when the equipment was damaged?

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I think it's quite unlikely that any microbes evolved on some other planet would be able to make humans sick. That applies most especially to viruses. Also, native-evolved organisms would (mostly) not find any (or much) food value in humans or parts of humans, nor in anything humans could find comestible.

The scenario of an alt.Eemian alt.Earth might have lots of living things of just about any size that could be dangerous to humans. Anything that was in the RL.Earth's RL.Eemian, for instance.

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But, anything I've said could be wrong, and that's why I'm asking everyone's opinion (and, particularly, why I'm asking your opinion!).

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For how much of the atmosphere is oxygen, we're looking at:
• 20.79%
• 21.21%
• 18.9%
• 23.1%
• 10.5%
• 42%
• 2.1%
• 97.9%

In the past, when all those giant insects were around, the Earth's atmosphere was 36% oxygen. At that concentration, one could have started a forest fire simply by striking a tree with a baseball bat -- if one could have been there with a baseball bat. So I think the 42% is kind of dangerous; at least unless atmospheric pressure is reduced to something close-ish to 0.5 atm.
I think 2.1% is clearly too little oxygen unless the atmospheric pressure is higher, say, about 10 atmospheres -- and that would be safe only if the excess were made up of something like helium or neon or argon, rather than nitrogen or carbon dioxide. (Neon might be best. Krypton might be OK, but argon is already heavier than carbon or nitrogen or oxygen, and even a bit heavier than chlorine; krypton is a trifle heavier than bromine, which is not gaseous at our real-life temperatures. Xenon is not totally inert; and radon is radioactive.)
97.9% would be even more dangerous than 42%, unless atmospheric pressure were reduced to 0.22 atm or thereabouts (my quick calculation could be wrong in detail, but I think the core concept is correct. If it isn't, let me know?).
I'm not sure 20.79% or 21.21% would really be distinguishable from RealLife Earth-"Normal".
18.9% and 23.1% ought to be easily tolerable, IMO, or at least, IMG (Is My Guess).

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Other variables I've played with have included:
• * The mass of the Sun
• The age of the Sun
• The luminosity of the Sun
• The "color" of the Sun

• * The masses of the Jovian "major" planets
• The number of "major" planets -- 1 (25%), or 2 (50%), or 3 (75%), or 4 (100%), or 5 (125%), or 6 (150%), or 8 (200%), or 40 (1000%).
• Their distances from the Sun
• Their orbital periods
• Their orbital eccentricities

• * The mass of the alt.Earth
• Its distance from the Sun
• Its period of revolution (its "year")
• Its orbital eccentricity (RL is 1%. Ten times that is 10%, which is what Mars's is IRL.)
• Its period of rotation (its "day")
• Its axial tilt: RL is 23.5 degrees. Any axial tilt greater than 90 degrees is impossible. Any axial tilt greater than 45 degrees results in "anti-Temperate zones"; the northern one, for instance, would be south of the Tropic of Cancer but north of the Arctic Circle. If I take 45 degrees as a max, the values would be * 22.275 degrees,
• 23.725 degrees,
• 20.25 degrees,
• 24.75 degrees,
• 11.75 degrees,
• 34.25 degrees,
• 2.25 degrees,
• and 42.75 degrees. OTOH if I take 90 degrees to be the max, the values are * 22.275 degrees,
• 23.725 degrees,
• 20.25 degrees,
• 24.75 degrees,
• 11.75 degrees,
• 45 degrees,
• 2.25 degrees, and
• 87.75 degrees.

• * Milankovich features:
• how much the eccentricity changes and how often
• how rapidly the planet's axis-of-rotation precesses
• how much and how often the planet's axis-of-rotation nutates ("nods")

• * The number of satellites; 1, 2, or 10.
• The mass(es) of the satellite(s)
• Their distances from the planet
• Their periods of revolution (their "months")

• Sea level:
• 1 or 2 or 3 or 4 meters higher or lower than RL
• 10 or 20 or 30 or 40 meters higher or lower than RL
• 100 or 200 or 300 or 400 meters higher or lower than RL

• The oceans' salinity

And there could be a few more, but right now I can't think of them.

A general tendency, I guess, is that,

• a difference of 1% (99% or 101% of "Earth-normal") might not be detectable by the colonists;

• a difference of 10% (90% or 110% of "Earth-normal") would be (mostly easily) detectable, but not so great as to drive the story

• A factor of 2 (50% or 200% of "Earth-normal") would be so great it would drive the story; therefore at most one feature could differ by that much.

• A factor of 10 (10% or 1000% of Earth-normal) would be so large that at most short visits could be made, and then only with great technological effort; no long-term missions, much less permanent residence, would be possible.

• Posted October 5th, 2015 by chiarizio
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Thank you, Elemtilas.
It looks like, in general, 99% to 101% Earth normal is probably just fine; 90% and 110% can be accomplished low-tech by "extremophile" humans; 50% and 200% are near the limits that humans can survive long-term, and in some cases require technology that would get in the way of, for instance, begetting and conceiving and bearing and rearing children; and 10% and 1000% are outside the range of survivability for humans.

I think that sounds about right. I dó understand you're trying to frame this as a plot device for a story, and (probably) not as a serious proposal for colonosing a real planet. In that regard, I would only suggest that you fear not taking some amount of artistic license! Your job, it seems, is to tell a compelling story rather than write a technical manual; so don't worry tóo much if some of the parameters are a little too out of whack.

Suppose a group of space-colonists landed, accidentally prematurely, on an alternate-Earth (without humans) near the area where the alt.Europe and alt.Asia and alt.Africa all come together, in the equivalent of an Eemian period. Now suppose everything after that happens ten times as fast as *here* on Consensus-Reality Earth in Our Time Line. There's an Ice Age, and a Toba-Disaster-equivalent; what order they come in I don't know. Then the Ice Age ends, then there's a Younger-Dryas-equivalent, and so on.

Is this a classic Star Trek alt.earth, or is this simply a planet similar to Earth in very many respects? I ask mostly because down below they seem to actually be on Earth, but at a different time. Or am I missing something??

Would the combination of an Ice Age and an alt.Toba-Disaster wipe out their technology, setting them back, essentially, to (some equivalent of) the Scientific Revolution and/or (some equivalent of) the Enlightenment?

If the volcano in question is nearby, it might just wipe all the colonists out! I'm guessing that these colonists will have some kind of space ship or craft that they came down to the planet with. I don't see why that would necessarily disappear just because a single super volcano erupts thousands of miles away. Surely, an already small, but well educated and technologically savvy population will face difficulties, but unless something happens to actually destroy the tech they came down with, I don't see a good reason why they'd lose it.

You seem to have placed them in a rather nice geographical location to be in during an ice age -- not so far north that they actually have to deal with the Ice, and not so far south that they'd have to deal with tropical conditions. They seem to be in a relatively temperate area. That could help them not only survive but perhaps thrive and expand even with the nastiness going on further north.

For right now, they seem to be a pretty small target and one that is still very well able to use their technology as well as understand and fix it. Maybe give them a few generations and spread them out a little more and you might have a scenario where a more dispersed technology can be more easily lost or destroyed. I'm not sure I have a good way to destroy the tech they brought with them -- unless it simply wears out! -- barring some disaster that will probably end up wiping out the colonists themselves.

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I'm assuming they'll lose the ability to make new records of the high-tech type they came with, or copy existing high-tech records, or search high-tech records by any means other than just reading through everything. But I'd like an in-story explanation of how and why that happened. What satisfies Occam's Razor better -- they crashed and all that equipment was irreparably damaged in the crash, or, they were caught by surprise by a flood or a freeze or a volcanic eruption, and that's when the equipment was damaged?

A good old fashioned crash-landing scenario might work best. Some, probably small, technology could survive, but the large pieces could be destroyed during the crash disaster. Even if they know the tech well, there'd be no way to fix it and no way to put in a service call to the Galactic Auto Association for a tow.

Frankly, I think a scenario where the tech survives, but without any kind of manufacturing plant can not be replicated and it eventually just plain wears out and becomes useless might be a more interesting tack. This will give your colonists enough time to spread out somewhat (and thus make the struggle to survive sub-threads more interesting as well as more plausible) and will also hand you an easy explanation for why the tech no longer works. By then, time shall simply have degraded the components sufficiently that they simply fail.

Eventually, people will learn to do without all the high tech and will gradually have to shift back a little, to rely on technology that they can easily make with what materials and processes they have available to them. The fancy stuff will fade into history, though may well be preserved against some future time when it can again be accessed and used...

Enter your disaster of choice and most likely the first thing to go will be knowledge of all that essentially fabulous technology. People will be more interested in getting enough food to eke out a survival. All those computers and laser guns and space ships will simply become the palantirs and vimanas of the next generations' nascent mythology...

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Here is a sort of story snippet, not about a disaster, but about a later generation of folk in the World coming across some of this high tech:

An unusual occurence happened at an ancillary Gate(*) some fourteen thousand years ago in the vicinity of western Lybia.

Two armies of competing proto-Archaic Empires in the region, one of which was almost certainly Atelantean, were advancing on one another when of a sudden, a powerful orange glow appeared in the space between the radiply closing warriors.

The men were all brought up short by the shimering, glittery light. From within the glowing light were heard subdued voices as of Men, though none knew what language they were speaking. At first no people of any sort could be seen, then in an instant, the voices became loud and many powerful gods appeared in the gleaming light bearing strange devices. One held aloft a brilliant and dazzling gem, glowing many colors from within a golden basket; another carried polished metal wands and a third bore a basket that issued forth a vapor like that of a mighty dragon.

The first called out mighty Words of command and a much brighter greenish light appeared before them. Without pausing so much as an instant, the lot of them tumbled through the green light. As the last one passed out of sight, their voices faded again; and then the two gateways of shimmering light faded and were gone.

Neither army moved and no man spoke. Every warrior was riveted to the spot, stunned and amazed by what they had witnessed. At last, the two leaders of the men approached one another at the place of the translocation. The men had already decided that no good could come of fighting on ground visited by the gods, and they began to disperse. The leaders had to accept the men's truce and parted ways.

One of the leaders, of the western faction, had seen a strange metallic object on the spot where the gods had passed through the world from one heaven to another and had the presence of mind to pick it up. It glinted in his hand as he returned to face the backs of his retreating men. He had no sense of what it could be or why it had been dropped. Was it an accident, or did the gods want for him to find it at that time? Who were these strange and talkative gods and what were they doing?

The translocation herein described follows a typical pattern of transfering from one ancillary Gate to another, there being typically no direct route. The device was almost certainly dropped by a Spacefarer.

Atelis was the name of that leader of the western faction, and his star was just about to rise, though little he could comprehend what the strange glowing box was capable of. For indeed the shining object Atelis picked up was a device of great power, and it soon brought great power and prestige to its new owner, who through the help of his brothers, both wise and learned priests, he became able to read the texts displayed upon its face and he understood the tongue of the gods.

Atelis was an ambitious man, living in an age when the ancient empire of Atelante was in decline, and her colonies were rising to prominence. The land that would one time bear the name Chemia was home to Atelis and his family, and it was not long that his godly knowledge allowed him to seize control of the newly forming kingdom. He learned much of the arts of alchemy, metal working, medicine and many other arts beside. This first pharaoh of the Chemians became a great man, but his heir was weak. After Atelis's death, the heir was unable to maintain control of the Artifact, and it passed into the hands of the priesthood of Imhotep, the healer.

In time, Chemia became a technotheocracy; while the pharaoh continued to wield considerable authority in the land, real power was wielded by the college of chief priests, especially those of Thoth, the god of writing, Imhotep, the god of healing and Nefertem, the god of alchemy. For a very long while, the priests were able to study the texts displayed upon the face of the gods' device, and their understanding of the world increased in great strides. Armies of scribes spent weeks and months in the cool of a deep temple complex copying and expounding upon the arcane wisdom of the gods.

At last, the power of the device itself seemed to wane, as if the voice and wisdom of the gods were fading from the world. The scribes redoubled their efforts at copying and translating -- but the chief priests became anxious. What would happen when the device no longer spoke godly knowledge to them? How would their learning advance; and there were still very many gaps in their understanding of what they had already learned.

At last, the device's display became so dim as to be unreadable, and the high priest of Imhotep declared that the voice of the gods would no longer speak through the device unless Chemia undertook a renewed worship of the gods. Perhaps through the ceaseless prayers of the people and the intercession of pharaohs past, the gods would again speak. It did not take long for Chemian science, never too secure in its foundations and never thoroughly understanding of the alien texts displayed in the device, to devolve into a mish-mash of garbled myths and legends and magical mumbojumbo.

In time, those early priests of Atelante and Chemia became deified in the lore of the people and the ancient history was forgotten. The device itself, now long dark, is still revered as a cult object, jealously guarded by priests that no longer know what their ancestors had once done with it. It now rests hidden in a deep dark subterranean shrine, far, far away from the light of day that, ironically, would activate the photocells on the object's surface, thus recharging its power cells. Yet Chemia went forth into darkness darkened by their ignorance of the object that had given them much light.

None can now fathom what the future might hold for this device. Will some intrepid scholar wrest it from the clutches of an ignorant and benighted priesthood? Will its secret be at last revealed?

NOTE: Gates are artifacts of elsewhere technology that allow the adept to travel quickly from place to place without bothering with slow caravans or ships prone to sinking in storms. If you can activate a sequence of Gates in the correct order, you can pass from one location to another thousands of miles away within a few minutes. The "gods" obviously know how to do this!
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You may also recall I wrote a story about an apocalyptic disaster that destroyed a highly technological society and decimated its population. A distant future had managed to re-evolve that technology, or something similar, and even chanced to discover and study some curious records of that previous age of technological enlightenment. And now that distant future and its government seeking to cover up all knowledge of that distant past is facing the old threat of apocalyptic destruction anew.

_____________________________________________________________

I think it's quite unlikely that any microbes evolved on some other planet would be able to make humans sick. That applies most especially to viruses. Also, native-evolved organisms would (mostly) not find any (or much) food value in humans or parts of humans, nor in anything humans could find comestible.

Possibly. But it really doesn't take much to make us very sick. A by-product of those microbes' metabolism could cause illness. For example, Claustridium itself isn't a problem so much as the botulinum toxin it produces.

The scenario of an alt.Eemian alt.Earth might have lots of living things of just about any size that could be dangerous to humans. Anything that was in the RL.Earth's RL.Eemian, for instance.

Sure. Wargs and orcs and fell dragons of all sorts!

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Lots of interesting things you've looked into already! I guess I'd only warn against not becoming bogged down in minutiae! Just let your colonists crash first and then discover what sort of planet they've crashed on (how different it is from Earth). Let them acclimate and then send in the destroying angels!

Posted October 6th, 2015 by elemtilas
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Is this a classic Star Trek alt.earth, or is this simply a planet similar to Earth in very many respects? I ask mostly because down below they seem to actually be on Earth, but at a different time. Or am I missing something??

I'm kind of flip-flopping about that. Perhaps it's an alternate-universe Earth, with a similar geological history up 'til the landing, but a biological history which diverged a little earlier (say 150 million years? less than 500 million, anyway), so that there aren't any "higher" primates (at least no apes, perhaps no monkeys either; maybe no primates at all). Or perhaps it's just a very Earth-like planet, where the crops the colonists brought could easily be cultivated, but most of the native life has not much in common with Earth life. I'll make up my mind eventually, I suppose.

A good old fashioned crash-landing scenario might work best. Some, probably small, technology could survive, but the large ….
knowledge of all that essentially fabulous technology. People will be more interested in getting enough food to eke out a survival.

Thanks! I think you're right.

All those computers and laser guns and space ships will simply become the palantirs and vimanas of the next generations' nascent mythology…

Palantíri
Vimāna

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Here is a sort of story snippet, not about a disaster, but about a later generation of folk in the World coming across
.…
intrepid scholar wrest it from the clutches of an ignorant and benighted priesthood? Will its secret be at last revealed?

Thanks for that!
Is The World an alt.Earth? How would you classify it, in regard to the question you asked me above?

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You may also recall I wrote a story about an apocalyptic disaster that destroyed a highly technological society and
….
cover up all knowledge of that distant past is facing the old threat of apocalyptic destruction anew.

No, I don't remember that story! Where is it? I want to read it!

_____________________________________________________________

Possibly. But it really doesn't take much to make us very sick. A by-product of those microbes' metabolism could cause illness. For example, Claustridium itself isn't a problem so much as the botulinum toxin it produces.

Indeed, there is a story I once read in which the native microbes could fatally infect a human, though it would cost them their own lives as well. The flesh of a person thus killed, suitably cooked, was a psychedelic that actually provided some "psi" powers.

Sure. Wargs and orcs and fell dragons of all sorts!
Lots of interesting things you've looked into already! I guess I'd only warn against not becoming bogged down in minutiae! Just let your colonists crash first and then discover what sort of planet they've crashed on (how different it is from Earth). Let them acclimate and then send in the destroying angels!

Seems to be good advice! Thanks.

Posted July 10th, 2016 by chiarizio
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Or perhaps it's just a very Earth-like planet, where the crops the colonists brought could easily be cultivated, but most of the native life has not much in common with Earth life.

This might actually be rather interesting. All sorts of room for strange and wonderful creatures to try and eat the survivors!!

Is The World an alt.Earth? How would you classify it, in regard to the question you asked me above?

Definitely not at alt.Earth. It is fundamentally different in some key respects. It's a place where love & karma & dwimmery & socks being lost on laundry day are every bit as much a part of the fabric of All That Is as gravity & electromagnetism & catatraction.

It's obviously a place where human-like people as well as non-human people can live & thrive. I have a notion that some time in the deep future, people from Earth itself will cross the dimensional rift and visit the residents of Gea.

Dunno how they'd do if they actually wrecked their ship. Probably okay. Humans from Earth are Not Quite Human as regards the Men native to Gea, but perhaps close enough that they could just fit in, if they crashed in approximately the right location.

_____________________________________________________________

You may also recall I wrote a story about an apocalyptic disaster that destroyed a highly technological society and
….
cover up all knowledge of that distant past is facing the old threat of apocalyptic destruction anew.

No, I don't remember that story! Where is it? I want to read it!

Buy the book! I did post it on Conculture years ago, and I'm pretty sure we had a chat about it:
https://groups.yahoo.com/neo/groups/conculture/conversations/messages/29366

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Indeed, there is a story I once read in which the native microbes could fatally infect a human, though it would cost them their own lives as well. The flesh of a person thus killed, suitably cooked, was a psychedelic that actually provided some "psi" powers.

Now, that's an interesting twist!

Posted July 10th, 2016 by elemtilas
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You may also recall I wrote a story about an apocalyptic disaster that destroyed a highly technological society and
….
cover up all knowledge of that distant past is facing the old threat of apocalyptic destruction anew.

No, I don't remember that story! Where is it? I want to read it!

Buy the book! I did post it on Conculture years ago, and I'm pretty sure we had a chat about it:

https://groups.yahoo.com/neo/groups/conculture/conversations/messages/29366

Thanks!
BTW Norbert Kohr ~=~ Albert Gore?

Posted July 12th, 2016 by chiarizio
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Thanks!
BTW Norbert Kohr ~=~ Albert Gore?

No worries, and yes indeed!

Posted July 14th, 2016 by elemtilas
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Bump

Posted March 1st by chiarizio
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Reply to: What conditions would support permanent human settlements?