Low gravity

With the understanding that inadvertent loss of contact with the seat of a commode while voiding one's bladder or straining at stool would be very messy, I would think that the wall-mounted grab bars common in restrooms fitted to accommodate the handicapped here on Earth would be even more prevalent on Ceres, though for an entirely different purpose.

Suppose a one hundred kilogram person abruptly ejects one kilogram  at two meters per second, his vertical velocity would only be two centimeters a second, which would only bounce him off the toilet for one third of a second, which would not be noticeable. 

Even Ceres gravity does not allow rocket propulsion by excretion.

DISTRACTION--As I said before, 'the story is the story.' Rather than have readers wonder why a guy in a hurry to toilet appears to be floating along horizontal, all we want him to think is, 'gee, the guy is in a hurry.'

This is entertainment.  I want distraction.  Show us that we are not in Kansas any more.

Superman comics regularly show superman posed in ways that would be inappropriate for a mortal. This society is cool and interesting because different from our own.  It is different because anarchic - but it is also different because it is in space.

The reader might well be confused by seeing a character acting as if in milligravity when everything else in the environment looks one gravity.  Less confused if multiple objects and people are showing milligravity movement. 

Satisfying picky readers without confusing casual readers is a hard problem - but showing that the environment is strange is not so hard a problem. 

Live action movies regularly use human actors with a silly decoration on their face to signify aliens, rather than full cgi aliens.  Makeup signifying that a live actor represents an alien species is silly, but it is at least a nod toward the purists.

Written dialog necessarily differs substantially from actual spoken dialog, and cartoon space is necessarily going to differ substantially from actual space, but we do need at least a nod that this is not taking place in Kansas.  The depiction does not need to be scientifically sound, but what is depicted needs to be something that could not  possibly take place in twenty first century Kansas. 

The fans will always gripe about scientific impurity, but at least show us that we are not in Kansas.

Donald Kingsbury wrote _Courtship Rite_, a story about people living in an alien ecology where the only food that wasn't poisonous was the Eight Sacred Plants, honeybees, and human beings. He did a great job with the ritual cannibalism etc. Lots of people got grossed out and didn't finish the story. There were little jarring notes all the way through, even when you'd think you'd gotten used to it. Like, late in the story, a general puts his maps into a babyskin tube....

An excellent novel.  Probably time for me to reread it, it's been a few years.  A bit of an inspiration to those in the polyamorous side of life.

Time to also reread The Moon Goddess and the Son, another fine piece by Kingsbury.  The novella was excellent, the expansion into a novel was great.  Another good novelette of his is "To Bring in the Steel", which happens to be about moving and mining asteroids.

Then we get to the hard one.  Psychohistorical Crisis.  It beat El Neil's The American Zone (which I voted for) for the 2002 Prometheus Award.  On the other hand, it's a better sequel to Asimov's Foundation series than anything ever written by Asimov or the "trilogy" by Bear, Benford and Brin (which also averaged much better than Asimov).  If you haven't read it, I highly recommend it.  It helps also to have recently read/reread Asimov's original "trilogy".  Not necessary to the story, but it's great to find the in-jokes.  (Also helps to have read his sundry robot stories and novels).

Among other things, the years of the Trantorian Empire are not baselined from AD on Earth.  The baseline starts tens of thousands of years later, after mankind had spread in all directions, mostly at sublight speeds, which would encourage lots of variation between widely separated communities without cross-breeding.  That's how evolution normally works.

The "Crisis" is simple (and this is not a spoiler).  For something like Psychohistory to work, there can only be one group with the secret to using/manipulating it.  This was also touched on in Michal Flynn's novel In the Country of the Blind, which won its own Prometheus eleven years earlier.

That [gecko shoes] won't give you vertical walking, though. Unless people don't mind the terrible disadvantages. Shinsplints? Bad angular momentum.

Actually, I think it might. It might look a bit funny, but as long as you have muscular ankles, you could stay vertical.

Suppose a one hundred kilogram person abruptly ejects one kilogram  at two meters per second, his vertical velocity would only be two centimeters a second, which would only bounce him off the toilet for one third of a second, which would not be noticeable. 

Even Ceres gravity does not allow rocket propulsion by excretion.

Physiology is not quite physics.

In defecating (particularly with formed stool in the rectal ampulla), increased thoracoabdominal pressure is entirely responsible for the expression of waste. In comparison with the urinary bladder, the large bowel is almost bereft of intrinsic muscle that might serve effectively in expelling solid stool. 

The Valsalva maneuver is a sequence of voluntary actions in which the individual inhales, closes the glottis, and by exhaling forcefully against the closed glottis, increases pressure within the thorax and abdomen.  Among other things, this serves to assist with the evacuation of both the urinary bladder and the rectosigmoid colon, the latter further facilitated by the individual assuming the seated position which the usual commode is specifically designed to facilitate, the torso flexed (leaning forward) so that within the distal large bowel, the sigmoid segment to some considerable extent "folds" over the top of the rectal ampulla to make of it a  chamber open only at the anus.

Think "toothpaste tube."

The value of this seated position is not to be underestimated.  Anyone who has ever had to employ a bedpan for defection can tell much about how damnably difficult it is to move formed stool while supine. 

If he or she can overcome the embarrassment.  There are reasons why nurses and physicians do not laugh when the expression "digital disimpaction" comes up in clinical discussions. 

"Body cavity search," sure.  "Digital rectal examination"?  Big funny.  But a bed-bound patient with a left hemicolon stacked full of hard stool represents a genuine hazard and real pain for the patient - in neither aspect trivial - as well as an exacting and thoroughly unpleasant intervention for the caregiver.  No friggin' joke.

Got all this clearly pictured?  Preadolescent sniggering set firmly aside, let us proceed to consider what else happens in the human body while taking care of the necessary function of ridding the digestive system of waste, particularly in what are called the "core" muscles of the abdomen and lower extremities, the muscles responsible for upright posture and bipedal ambulation in a one-gravity field. 

In bowel movements, these muscles are being exerted as well, and bear in mind that on Ceres the insufficiently cautious exertion of the foot's plantar flexor muscles - just the muscles in the calves, the gastrocnemius and soleus - has been depicted correctly as sending the newcomer literally crashing against the ceiling. 

The "lift-off" potential while straining at stool ought to be apprehensible to anyone.

While I would counsel diets high in both soluble and insoluble fiber (as well as oral consumption of surfactants like dioctyl sodium sulfosuccinate) for anyone considering a life in microgravity, no matter how soft and bulky the colonic contents are kept, it is necessary to engineer bathrooms to handle human physiological functions that must cope with formed bowel movements and constipation. 

Anybody who wants to get cute about that they think are the physics of defecation without taking into consideration the biomechanics involved in coping with this inescapable requirement of human life is invited to come along on hospital or nursing home rounds with any average geriatrician. 

Like I said, no friggin' joke.
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That [gecko shoes] won't give you vertical walking, though. Unless people don't mind the terrible disadvantages. Shinsplints? Bad angular momentum.

Actually, I think it might. It might look a bit funny, but as long as you have muscular ankles, you could stay vertical.

I'm going by my imagination, which is often defective. I imagine you'd need to strengthen the muscles in front of your lower legs. Awkward. But there could be a better way that I would find with experience but not with foresight.

So with disclaimers, if the way I'm thinking of it is correct, what value do you get by walking erect? In my imagination, it looks like it would be harder and less efficient than swimming erect which is also possible. Far easier to travel horizontally; the more horizontal you can manage the less of that bad lever arm you have to deal with. Something like an infantryman's crawl, with the knees out to the side, but faster.

Once you're at your traveling speed in a mostly straight line, your losses are mostly to air resistance and you have to keep pushing on the floor occasionally so you don't slide on it.

... what value do you get by walking erect?...

A million+ years of walking erect has created a physiological and psychological bias for being upright around other people. Even in zero g, people at rest usually align themselves to an arbitrary, but common "vertical." In zero g, head-first is used for rapid travel, but astronauts--with the use of their hands--do move around areas slowly with their bodies at right angles to the direction of travel. In micro-gravity it would probably be the same--especially with the use of gecko boots. So, "value" is not as relevant as practice. For whatever reason, humans prefer to be aligned with each other and in micro-g, that means vertical. So that is what I think would happen irrespective of whether we see "value" in it or not.

"It was a dark and stormy night..." 

Physiology is not quite physics.

In defecating (particularly with formed stool in the rectal ampulla), increased thoracoabdominal pressure is entirely responsible for the expression of waste. In comparison with the urinary bladder, the large bowel is almost bereft of intrinsic muscle that might serve effectively in expelling solid stool. 

The Valsalva maneuver is a sequence of voluntary actions in which the individual inhales, closes the glottis, and by exhaling forcefully against the closed glottis, increases pressure within the thorax and abdomen.  Among other things, this serves to assist with the evacuation of both the urinary bladder and the rectosigmoid colon, the latter further facilitated by the individual assuming the seated position which the usual commode is specifically designed to facilitate, the torso flexed (leaning forward) so that within the distal large bowel, the sigmoid segment to some considerable extent "folds" over the top of the rectal ampulla to make of it a  chamber open only at the anus.

Think "toothpaste tube."

The value of this seated position is not to be underestimated.  Anyone who has ever had to employ a bedpan for defection can tell much about how damnably difficult it is to move formed stool while supine. 

If he or she can overcome the embarrassment.  There are reasons why nurses and physicians do not laugh when the expression "digital disimpaction" comes up in clinical discussions. 

"Body cavity search," sure.  "Digital rectal examination"?  Big funny.  But a bed-bound patient with a left hemicolon stacked full of hard stool represents a genuine hazard and real pain for the patient - in neither aspect trivial - as well as an exacting and thoroughly unpleasant intervention for the caregiver.  No friggin' joke.

Got all this clearly pictured?  Preadolescent sniggering set firmly aside, let us proceed to consider what else happens in the human body while taking care of the necessary function of ridding the digestive system of waste, particularly in what are called the "core" muscles of the abdomen and lower extremities, the muscles responsible for upright posture and bipedal ambulation in a one-gravity field. 

In bowel movements, these muscles are being exerted as well, and bear in mind that on Ceres the insufficiently cautious exertion of the foot's plantar flexor muscles - just the muscles in the calves, the gastrocnemius and soleus - has been depicted correctly as sending the newcomer literally crashing against the ceiling. 

The "lift-off" potential while straining at stool ought to be apprehensible to anyone.

While I would counsel diets high in both soluble and insoluble fiber (as well as oral consumption of surfactants like dioctyl sodium sulfosuccinate) for anyone considering a life in microgravity, no matter how soft and bulky the colonic contents are kept, it is necessary to engineer bathrooms to handle human physiological functions that must cope with formed bowel movements and constipation. 

Anybody who wants to get cute about that they think are the physics of defecation without taking into consideration the biomechanics involved in coping with this inescapable requirement of human life is invited to come along on hospital or nursing home rounds with any average geriatrician. 

Like I said, no friggin' joke.
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Razzafrazzin', grumble, mumble...no need to get upset by my comments.  As I said before, good design isn't always visually obvious. 
And I assumed water was used for flushing because there was an upright tank in the back, like a normal toilet. If water isn't being used, I can't see much purpose for the tank being there.  But I certainly can understand a desire on the artist's part for an immediately obvious visual cue.

Again, no need to be upset--just a nitpicky little detail. 

I don't know about you but I'd feel more comfortable sitting on a toilet that looks like a toilet, and not the robot from Lost In Space. Have you SEEN the ISS toilet? It scares the hell out of me.

Ooh, the horrors of 'going' in space.

I haven't seen the ISS toilet though. But under any circumstances I'd be much more concerned about the stuff that's coming out of me than the equipment that's been designed to keep that stuff from getting back to me.

And I assumed water was used for flushing because there was an upright tank in the back, like a normal toilet. If water isn't being used, I can't see much purpose for the tank being there.  But I certainly can understand a desire on the artist's part for an immediately obvious visual cue.

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I could come up with all sorts of reasons why that tank was mounted the way it was, including the necessity to house whatever mechanism might be required to ensure that wastes of whatever kinds are safely collected and conducted away for utilization.

Think back on Heinlein's work at making Luna a believable plenum in The Moon is a Harsh Mistress (1966).  Early on, the protagonist attends a meeting in Luna City, recounting one part of it thus:

Several farmers bellyached and one wheat farmer was typical. "You heard what Fred Hauser said about ice. Fred, Authority isn't passing along that low price to farmers. I started almost as long ago as you did, with one two-kilometer tunnel leased from Authority. My oldest son and I sealed and pressured it and we had a pocket of ice and made our first crop simply on a bank loan to cover power and lighting fixtures, seed and chemicals.

"We kept extending tunnels and buying lights and planting better seed and now we get nine times as much per hectare as the best open-air farming down Earthside. What does that make us? Rich? Fred, we owe more now than we did the day we went private! If I sold out — if anybody was fool enough to buy — I'd be bankrupt. Why? Because I have to buy water from Authority — and have to sell my wheat to Authority — and never close gap. Twenty years ago I bought city sewage from the Authority, sterilized and processed it myself and made a profit on a crop. But today when I buy sewage, I'm charged distilled-water price and on top of that for the solids. Yet price of a tonne of wheat at catapult head is just what it was twenty years ago. Fred, you said you didn't know what to do. I can tell you! Get rid of Authority!"

All through history (and in many places in Asia today), farmers have not only handled disposal of human solid waste but have relied upon it as an important source of fertilizer. The ISS septic system treats such waste as a problem that builds up and requires "packaging" for removal.  Wouldn't a necessarily self-contained artificial ecology such as we'd see in the belt treat it instead as raw materials?  As Heinlein put it so many decades ago (by way of Wyoming Knott's reply to the audience in which that farmer presented himself):

"You! You're a wheat farmer — going broke. Do you know how much a Hindu housewife pays for a kilo of flour made from your wheat? How much a tonne of your wheat fetches in Bombay? How little it costs the Authority to get it from catapult head to Indian Ocean? Downhill all the way! Just solid-fuel retros to brake it — and where do those come from? Right here! And what do you get in return? A few shiploads of fancy goods, owned by the Authority and priced high because it's importado. Importado, importado! — I never touch importado! If we don't make it in Hong Kong [Luna], I don't use it. What else do you get for wheat? The privilege of selling Lunar ice to Lunar Authority, buying it back as washing water, then giving it to the Authority — then buying it back a second time as flushing water — then giving it again to the Authority with valuable solids added—then buying it a third time at still higher price for farming — then you sell that wheat to the Authority at their price — and buy power from the Authority to grow it, again at their price! Lunar power — not one kilowatt up from Terra. It comes from Lunar ice and Lunar steel, or sunshine spilled on Luna's soil — all put together by loonies! Oh, you rockheads, you deserve to starve!"

The belter civilization on Ceres does not have the predatory imposition of a government - an "Authority" - to thieve away the value of their efforts.  Water is a valuable commodity. Urea and ammonia ditto.  And organic solids suitable for composting (or however such matter can be processed to kill enteric pathogens and make it safe for use as fertilizer) even more valuable.

Whatever entrepreneurs on Ceres address the business of harvesting human waste products for resource extraction might well find themselves in a highly competitive market segment.  Think of publicly accessible "pay toilets" that offer a small inducement (some kind of token or coupon or other consideration, if not a bit of precious metal) to the user based upon the mass of the "contribution" graciously provided.

It's a whole new world up there....
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Urea and ammonia ditto.  And organic solids suitable for composting (or however such matter can be processed to kill enteric pathogens and make it safe for use as fertilizer) even more valuable.

Whatever entrepreneurs on Ceres address the business of harvesting human waste products for resource extraction might well find themselves in a highly competitive market segment.

All true. I cannot find the actually quote, but Buckminster Fuller said something like, "There is no pollution, only misplaced resources."

However, you don't even need entrepreneurs. Home fabs could use the waste to pump out water and sterile fertilizer for use in the family garden.

However, you don't even need entrepreneurs [to exploit the resources represented by human waste]. Home fabs could use the waste to pump out water and sterile fertilizer for use in the family garden.

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First, I tend to think of the belter civilization depicted thus far in Escape From Terra as cosmopolitan and sophisticated despite the fact that it's primarily a frontier society.  Not everybody is living in family habs.

Second, there are boarding houses, and it's obvious that a lot of the traffic flowing through Ceres' business district is transient.  People running services catering to customers' needs would almost certainly not have time or energy to put into taking care of those family gardens when attention paid to a going business gets more grams of gold (or other units of exchange) into one's accounts.  Those who have home fabs aren't dwelling in them all the time, and a lot of people might be simply living aboard ships or in quarters at work sites where there are no family gardens of any kind. 

Think about the American West and the various resource extraction activities - lumbering and mining camps in particular - and construction projects where single men (men and women, in the belt) came first, and families came later.  There would tend do be a lot of such single folk roaming the belt, their families (such as they might have) established safely elsewhere, possibly in the belt, possibly on Mars or Luna.

Third, consider both economies of scale and division of labor. Small "penny packet" waste processing can certainly be made practicable at the family hab level, even with today's technology, but the capital investment and impositions of maintenance are likely to be off-putting even with the theoretical "gray goo" capabilities of nanotechnology or whatever other kind of phlogisticated handwavium the writer cares to confabulate.

How many Americans today keep a milch cow on the property - as even suburban families used to do more than a century ago - when safely pasteurized and conveniently homogenized milk is by comparison cheap despite government price supports pushing up the dollar-denominated cost at the store?

A commercial concern set up to efficiently collect and process human liquid and solid wastes in the belt might do pretty damned well. It's not glamorous work, but consider a fleet of "honey wagon" transports making the rounds of work camps collecting dessicated flup and such (water scavenging would almost certainly be an easy capability to incorporate at point-of-service), transporting it to floating processing facilities which might themselves be easily shifted around in the belt or associated with hydroponic "farms" arrayed in microgravity to catch the sunlight, or buried away in darkness to grow edible and medicinal fungi.

In America, recycling is largely an insanity, economically nonviable from start to finish.  I strongly suggest attention paid to that episode of Penn & Teller's series Bullshit! (29 April 2004) in which they presented a pungent but robust refutation of the environmentalist stupidity of the practice.

In the belt, however, there's definitely the potential for industrial-scale exploitation of human waste as a resource. 

I can't imagine a culture that could produce a gram-grubbing little girl like Babbette the Younger which wouldn't give full rein to people who'd jump at the chance to turn sewage into valuta.
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First, I tend to think of the belter civilization depicted thus far in Escape From Terra as cosmopolitan and sophisticated despite the fact that it's primarily a frontier society.  Not everybody is living in family habs.

Of course their will be processors and transporters of waste products. However, I think it is quite reasonable for sophisticated Belters to have gardens of flowers trees and grass. Habs would surely have internal "back yards" and live-aboard ships would have some growing plants just for aesthetic reasons.

In the business areas, the merchants association or mall owners would collect waste and either process it and either use it in their parks, sell it directly to the farm towers or job it out to your entrepreneurs. 

Of course their will be processors and transporters of waste products. However, I think it is quite reasonable for sophisticated Belters to have gardens of flowers trees and grass. Habs would surely have internal "back yards" and live-aboard ships would have some growing plants just for aesthetic reasons.

In the business areas, the merchants association or mall owners would collect waste and either process it and either use it in their parks, sell it directly to the farm towers or job it out to your entrepreneurs. 

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The "sophisticated Belters" of whom you speak rather qualify as hobby farm types. They might crank out food items or cut flowers of commercial value, but the scale of production against inputs is going to be less efficient than can be gotten when people (either individually or in concert) specialize to meet market demand.  At best, they're likely to wind up akin to those friendly neighbors who keep dropping by with baskets of eggplants or zucchini which would otherwise go into their compost piles, 'cause they've canned or frozen more than they can use in three or four years and they're dead sick of eating the fresh stuff. 

(Yeah, I both saw and remember Mr. McGregor burying Alton Brown in aubergines in the "Deep Purple" episode of Good Eats, 16 January 2002.)

Ceteris paribus, most Belters seeking nutriment - fruits, veggies, what have you - as well as the colorful and scented reproductive organs of plants - are going to want these commodities at best possible prices, which the hobby farm types aren't going to be able to do in their family hab gardens.  Once the small-time producers figure in their costs, the prices they're going to set will turn out to be relatively high, and whenever you've got relatively high prices and demonstrable demand....

Ka-ching! Captialism happens.

Somebody will inevitably float (in microgravity, I mean literally float) ways to achieve productive economies in serving these markets, very likely in a vertically integrative fashion that also carries away the waste that unsophisticated Belters do not - for reasons of time, available growing volume, or just plain not wanting to bother - seek to exploit in their own gardens.

Maybe they'll have to pay to get it, but bear in mind that if the, er, producers of the flup set their prices for these organic solids beyond market clearing levels, they're going to get stuck in the deep.... 

Well, you get my point.
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