Tag Archives: science

632. Dam Gravity

M. Rehemtulla for QUOI Media Group

Tuesday morning. When I wrote these posts about two weeks ago, I mentioned PG&E. Guess what? They just announced that tomorrow my county is slated for a possible shutoff of power because of projected high winds. Even if that doesn’t happen, a regular power outage is likely. While you are reading this, there is a good chance I will be reading a book by sunlight through the window, because I won’t have any electricity to power my computer. I would find that ironically amusing, except my stove and refrigerator also won’t be working. At this moment I might be eating cold beans out of a can.

Additional, 6 hours later, it is now almost certain that we will be blacked out, and that it might well last up to five days. Posts come to you from WordPress, not directly from my computer, and I have a month of posts in the can so, see you later. Now back to what I already wrote.

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This is a continuation of last post. What does a kid with a toboggan have to do with solar energy storage, you ask? You’ll find out by the end of the post.

If you have any science background at all, please forgive the next few paragraphs as I set things up for something you may not know.

A battery does not hold electricity like a can holds Coke. The electrons which are present inside the battery do not go into your device. They travel from the (-) pole to the (+) pole, and essentially the same electrons are there in a discharged battery as are in a charged one.

It is the flow itself which powers your device. The flow is caused by chemicals inside the battery changing from a high energy configuration to a low energy one. This is true of the lithium ion battery that just burned up your hoover board, and equally true of the car battery in your great-grandad’s 1950 Nash Rambler. Such batteries are recharged by running electricity back through them to return the low energy chemicals to a higher energy state.

In other words, batteries don’t store electricity, they store energy. Chemical energy, and there are many other ways to store energy besides batteries. Let’s look at one.

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Last post I invited you to take a trip with me from the California foothills toward the coast. Now we have dropped down out of the brown hills, have crossed the hot, flat, agriculturally green Central Valley, and suddenly our car turns its nose upward because we have reached the Coast Range which stands between us and the ocean. We are on Highway 152 and to our left is the imposing dam of San Luis Reservoir.

Everyone knows the story of rainfall on mountains. California lives on it. Sunlight on the Pacific raises moisture which gets an uplift first by the low Coast Range and then by the High Sierra. The west side of the Coast range and the western Sierra foothills get winter rain in moderate quantities, and west side of the high Sierras gets a big dump of snow which melts in spring to fill reservoirs all over the western foothills, providing irrigation and electricity to California.

The eastern side of the Coast Range and of the Sierras get squat.

Where San Luis Reservoir is located, there isn’t enough local rain or snow to fill it. Water is brought to it by a system of canals, accumulated in the forebay and pumped up into the reservoir.

Sounds goofy, right? The dam exists to harvest in spring and store for summer, water that has already passed thorough the other reservoirs and would otherwise go to the ocean. Of course it’s controversial; everything related to water in California is controversial.

So what does this have to do with solar cells on the roof? San Luis Reservoir not only stores water, it is essentially a giant storage battery for electricity.

When the water arrives at the forebay, it is pumped, by electricity, up about 320 feet into the reservoir. When it exits the dam to be used, it passes through a hydroelectric generator, recouping much of the energy originally used to lift it. It isn’t 100% efficient system, but nothing is.

Batteries store energy by chemical change. There are innumerable other ways to store energy, many of them new, complicated, expensive, and with unknown dangers. Carrying a load uphill to store gravitational energy, and getting that energy back when the load comes down is old, simple, and well known. Kids have been doing it with toboggans ever since there have been snow, toboggans, and kids. (See, I told you I’d explain that photo.)

In California, people have been doing the same thing for a hundred years or more in tankhouses, water tanks attached to houses which allow gravity flow so you don’t need to turn the well pump on every time you open a faucet. The one shown here even used wind power to get the water out of the well and up into the tank.

This was done for the sake of the water, but it could as easily be done for the sake of storing energy. With twin tanks, one high and one low, there would be no reason to “use up” the water. It could even be structured in tandem with the house’s normal water usage.

I submit that a good engineer could turn this into a cheap, simple, and easy way to harvest solar power all day and use it all night, without frightening Mother Nature. You would simply use excess solar electricity to pump water upward all day, and drain it back through a turbine and generator that night.

How much water, how high would we have to pump it, how much would the raised tank cost? Would it be practical? Would it make money for the ones who provide the system? Who knows; that’s for some young engineer is search of a project to determine. Will it be you?

Since I didn’t invent this technique, I can’t ask for royalties once you perfect it. I will, however, expect a finder’s fee.

And if any of you out there know of someone who is already doing this, I would love to take my tongue out of my cheek and hear about it.

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631. To Grid or Not To Grid

Although I fully believe in it, I normally steer clear of talking about global warming, wind and solar power, and the impending end of civilization. There are plenty of sources for that, and I don’t want to get caught channeling PBS.

However, speaking of PBS, there was a bit about the problems of energy storage as part of the solar solution yesterday (Sept. 27) that made me realize I knew a few odd things from a few odd sources that were worth sharing.

I live in California, in the foothills of the Sierras. PG&E provides my electricity, but every time it rains more than a tenth of an inch, my power goes out for six hours. This has been true for decades, not just since PG&E went bankrupt for its role in recent fires and told us all that it was going to shut our power off every time the wind comes up.

It’s enough to make you want to go off the grid.

We’ve all grown up with the grid — even me. The first house I remember, about 1950, had no plumbing, no running water, and an outhouse out back, but it had electricity coming in from elsewhere through the wires. Consequently, I can’t honestly tell Lincolnesque tales of reading by a coal oil light (except when tornadoes took the wires down).

The history of the grid goes back to Tesla and Edison fighting the battle of AC vs DC, and continues through the REA. (That’s the Rural Electrification Administration which brought electricity to isolated farms throughout America in the thirties.)

The grid is wonderful; it has given us our present level of civilization.

The grid is terrible. It is a dinosaur, completely out of date and tying us to the mistakes of the past.

As is so often the case, both of those statements are true. No one decided to choose centralized production of electricity with a massive distribution system. Its alternative, dispersed production, was simply not an option in the past.

That is no longer the case. A system of solar power through electrovoltaic cells can now be built one roof at a time. (There are other alternative sources of electricity, but I’m only going to talk about one in this post.)

There is a big problem, though. Solar cells only generate sufficient power during reasonably sunny days. There is also a solution, but it is only going to work for a few years.

In today’s installation of rooftop solar cells, homes mostly draw on the grid at night and “turn the meter back” during the day. Quite clever, for now. It amounts to using the grid like a giant storage battery. But if enough rooftop solar installations try this trick, daytime generated electricity will become essentially a waste product from the viewpoint of the owners of the grid.

Of course you could have a mega-array of solar cells in America lighting up India at night, and a similar array in India lighting up America at night, but that’s turning the grid into a GRID. It’s good science fiction, but not very practical.

If you want off the grid — and eventually the grid will want you off, if you are a daytime energy generator — you will have to find a way to store your daytime energy for night time use.

Storage batteries are heavy and expensive, not only in the owner’s dollars but also in terms of world resources. They also blow up. I’m not just talking about lithium ion batteries; car batteries blow up too from time to time.

If you could invent the perfect battery — light, safe, cheap, environmentally friendly, capacious — it would make you more money than cold fusion.

If you could invent both, you would solve all the world’s problems except overpopulation and religious strife. You could run for God and probably win.

Heinlein invented the perfect battery, the Shipstone, and built a whole universe around it, but it’s harder to do in the real world.

Coming back down to the individual home owner, what is needed is a non-battery source of energy storage to make those solar cells practical.

I have an idea! Actually it isn’t mine; it already exists, and I can point to it.

Hop in the car with me and let’s take off for the coast. I drive by something every time the foothills get too hot and I need a Monterey fix down by the ocean. I’ll show it to you.

We’ll go there Wednesday.

626. Lucifer’s Cousin

In post 575. Textbook: The Rolling Stones, I mentioned the two interpretations of the asteroid belt that were current when I started reading science fiction. At that time, many believed that it was the result of the fourth planet being somehow blown up. There were plenty of science fiction stories about that lost planet’s civilization, including several which made it the source of humanity and the origin of the Atlantis myth.

The other interpretation was that the fourth planet was kept from forming by Jupiter’s gravity. A logical and prosaic theory and apparently the correct one. Occasionally, ignorance is bliss when writing science fiction. Does anyone else miss a swampy, dinosaur infested Venus?

Oh well, that’s okay. That’s what steampunk, fantasy, and alternate universes are for.

In Dreamsinger, I’ve managed to retrieve just a tiny touch of the old glory of an asteroid belt from an exploded planet, and it only came to me within the last few weeks. I had already tilted Stormking, way back when I was writing Cyan. The culprit was a rouge body passing through the Sirian system. I didn’t have to invent that; scientists believe that’s the way Uranus got tilted. I recently decided to make further use of it the rogue body by having it do major damage to planet number two.

I gave it a near miss. I may change my mind about that and give it a bullseye. I may even have my page-people discover that their scientists were wrong; that it wasn’t a near miss but a hit. Or maybe a so-near miss that the rogue was captured and is now part of the Swarm.

Here’s how it fell out in today’s (August 28th) rough draft.

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Dreea was assigned to the cargo ship Typhoon. It seemed a silly name for a ship of space, especially one completely without streamlining. If it ever encountered a typhoon, it wouldn’t last thirty seconds.

Sirius was massive, and it’s system reflected the fact. The distance to the Goldilocks region was about five times as far as Sol to Earth, but it wasn’t a blown up model of the old Earth system. Having a second, shrunken star was enough to see to that, but it did have a hot planet close in and a more-or-less Earth sized planet in the third position. The planet which had held Venus’s position had been broken up by the same rogue body that had tilted Stormking.

That was important, and it was the reason that the Swarm was Typhoon‘s first destination.

The fourth planet in orbit of Sol had never coalesced because of perturbations from massive Jupiter. Consequently, all the asteroids in the belt were more or less uniform in composition. The beltmen of Sol had made a living there, but it had not been rich pickings.

The Venus-position planet circling Sirius had fully formed, with a core and tectonic plates. For billions of years gravity and convection has stirred the stuff of the second planet, and accumulated various minerals in their various places. Then the rogue body had passed so close that tidal stresses had shattered number two.

Pebble sized, and rock sized, and boulder sized, and mountain sized and continent sized chunks of the planet had been torn apart. The heat released had been tremendous. The outward force had been tremendous, but so was the combined gravity of all the pieces. Coalescence began at once, but gravity had to fight tidal forces, lateral velocities, and new heat energy when the pieces crashed together again.

After half a billion years, it had still not fully coalesced. It was still a mess, but it was a rich mess. It was as if someone had picked the Earth up, hit it with a giant hammer, and left all it’s mineral riches out in the open for easy exploitation.

Typhoon was to drop in, pick up a cargo of various minerals, and then proceed to Forge, the innermost planet where Sirius’s heat was abundant and open-air factories would turn Typhoon’s cargo into the goods needed throughout the system.

If you can call a factory open-air, on a planet whose atmosphere was long ago boiled away.

619. The Crash Heard Round the World

Two days ago on the news, a Tesla driver was caught on camera asleep at the wheel on a freeway. We all got to see him snooze, then eventually got to see him jerk awake. Chit-chat ensued. One talking head said, “Someday sleeping at the wheel will probably be legal and safe.” Another replied, “Not in my car!”

When I was ten years old, everybody knew that men would never walk on the moon. In the subsequent decades, the public’s default position on what science plans to do has switched from can’t to can. The public isn’t any smarter; they’ve just changed their prejudices.

Driverless cars have been around for a long time in science fiction. Here is page 2, paragraph 1 of Methuselah’s Children by Heinlein, first published in 1941.

Mary had no intention of letting anyone know where she was going. Outside her friend’s apartment she dropped down a bounce tube to the basement, claimed her car from the robopark, guided it up the ramp and set the controls for North Shore. The car waited for a break in the traffic, then dived into the high-speed stream and hurried north. Mary settled back for a nap.

Good fun in ’41, but no one would have expected to see it happen this soon. Even science fiction aficionados might have said 2119, or maybe 2219, yet here we are, on the brink.

In 1941, the world was very different. Heinlein might imagine driverless cars, but he never imagined something else that is now part of our world — computer hacking.

Hang on, folks, I’m going to make a prediction.

At a near future date every car on the highway will be driverless. The old curmudgeons like me who wouldn’t even trust cruise control will all be dead, mostly from auto crashes with drivers who did trust cruise control. The text-and-drive crew will have won the battle of the public consciousness. Science will have proved that humans are inferior to computers in driving, and science will be right because it will be comparing computers to the text-while-driving generation. Human drivers will be outlawed as unsafe — which they will be.

Driverless cars will talk to each other and to central control, adding another layer of safety to the whole enterprise. Central control will be heavily protected against hacking, for obvious reasons. Science will prove that central control is impenetrable.

Science always proves something like that, just before the cataclysm. See Three Mile Island and Chernobyl.

All that was just set-up for the prediction.  Here is the prediction.

Sometime in August of 2035, a kid named Morrisey, who isn’t even born today, will hack the un-hackable central control. No one will notice. He will place a delayed command, and head for a hill overlooking an LA freeway.

On August 26th, 2035, at peak rush hour, central control will send out an order and every automobile in America will speed to 100 mph, then simultaneously make a ninety degree left turn.

Registering 4.6 on the Richter scale, it will be the Crash Heard Round the World.

St. Peter will have to put on extra staff.

618. Digging Up the Dead

I would love to show the excavations I took part in
but I have no such pictures.
This eyecatcher is an excavation of a
Roman site in London.

Last post I told about doing survey archaeology in Michigan in 1967, ending with the statement that suddenly, when the summer was almost over, everything changed . . .

We got a phone call from the University, and within hours we had packed up, left our base, and were heading half way across Michigan to Bay City.

The Sagnaw River runs through Saginaw, then northward about twenty miles to Bay City where it empties into Lake Huron. It is a major shipping channel which frequently silts up. In Bay City, a project was under way to dredge the shipping channel. An area along the river had been designated to receive what the dredges removed.

The dozers preparing to receive the outflow exposed human remains and everything came to a stop. The police came, but it was clearly not a crime scene. The remains were skeletons in what little remained of wooden coffins, surrounded by grave goods. It was an Indian burial ground.

Yes, Indian. That’s what they were called in 1968 and it was just a designation, like Dutch or French. It wasn’t an insult word. There were plenty of insult words, like redskin, but Indian was just a word. It still is.

Mr. Fletcher, who owned the site, gave permission to Michigan State to do salvage archaeology. We had two weeks to work before the bulldozers were scheduled to go back to work.

When we arrived on the site, we found a flat basin a hundred yards wide and a quarter of a mile long, of mostly pure sand. Those are “close enough” figures from memory. Bulldozers were impatiently poised to return to work.

The site was surrounded by dikes, perhaps twenty feet high. Once we were finished, the dredgers would pump a slurry of sand and water from the river bed into the basin, the water would make its way out through the sand dikes, and whatever remains we could not remove would be lost forever under twenty feet of fill.

There were four archaeology crews out that summer. Three of them had specific tasks that could not be abandoned. Our survey work could be done any time, so we were elected.

It was frantic work. The site, we learned eventually, dated from about 1750. The Indians were in contact with traders and settlers, both English and French, and the graves were full of trade goods. There were a lot of copper pots. Other than bone beads (well preserved) and furs which were barely recognizable, most of the grave goods were of European origin. That did not mean that these were westernized Indians, only that they had trading relationships.

We found a lovely silver cross, but that did not mean the deceased was a Christian. We found a flintlock pistol — or rather, a lump of rust that had once been a flintlock pistol. We found the remains of a musket, badly preserved; the wood was marginally better preserved than the iron.

One of the skeletons we found had a row of brass buttons down its sternum and scattered in the dirt in the belly area, along with tarnished epaulets above the points of the humeri. There was no fabric, but he had clearly been buried wearing a military great coat. That didn’t mean he was a scout for the French or the English (there wasn’t enough remaining to know which), although he might have been. He might also have traded for it, or have taken it off a dead European after combat.

Despite the hype about pyramids and Schliemann finding Troy, there is much that can be implied by an archaeology site, but much less that can be proved.

When I say skeletons, you should not picture the dead happy pirates of Pirates of the Caribbean. Bones do not last well in moist ground, and not all bones are created equal. Skulls and femurs last better than pelvi and ribs. The bones of the hands and feet don’t preserve even that well. Tiny bones hardly last at all. There were miniature coffins for infants, but they were pretty much empty, with maybe a few grave goods and a few flakes of skull.

I have to touch on the morality of all this. These were Indians buried by their own people. How would you like to have someone digging up the graveyard where your grandmother is buried? There are valid complaints to be made which I understand and have no intention in arguing against.

This particular case, however, was salvage. To me, it was no different than salvage of European bones. If during the construction of a modern building, a two hundred year old white folks cemetery was discovered in the basement excavation, the bones would be removed and reinterred. You may not realize it, but those bones would certainly pass through the hands of physical anthropologists who would study them for what they had to tell about the history of disease in early America, before being returned to the earth.

We were careful with everything we found because every piece had a story to tell. I spent hours drawing the remains in situ before they were removed, and hours with an alidade (described in post 586) making sure that the locations were well mapped.

We were careful with bones and copper pots, but we didn’t treat either as sacred objects. A pot is not a meal, and a bone is not a person. Everything went to the museum and the bones were, I believe, eventually reburied.

There are a few more personal bits to this story. My future wife was also on archaeology crews those two years, but not with me. She lived in Saginaw, and when she came home for the weekend during our salvage operation, she drove up to the site and volunteered to help.

When someone asks me where I met my wife, I say we met in a graveyard. Then I explain further. The following winter, she and I worked together upstairs in the MSU museum cataloging the results of the dig. Two years later, we were married.

The site was so rich that the land owner had it diked off. The dredging went on, but the fill went elsewhere, and the site was not lost. I spent the following summer there, this time accompanied by my college roommate. The site later became a field school, and my roommate wrote up the results as his Ph.D. dissertation. It is on line. The site ended up on the National Register of Historic Places, and has its own brief spot on Wikipedia.

Archaeology wasn’t an occupation I could continue, but I wouldn’t have missed the experience for the world.

617. Raiders Before the Ark

Ground penetrating radar used in survey archaeology.
I’m jealous; in 1967, we just walked and looked.

Anthropology has been a major part of my life. I spent five years in pursuit of it, and it forms the backbone of everything I think and write, even though my dislike of field work was pushing me away at the same time that writing was drawing me away.

When I discovered the field during the sixties, forensic anthropology was nearly unheard of and the tools of modern physical anthropology were just being assembled. Social anthropology, my specialty, and archaeology were the two choices for students then, and we all took classes in both.

My first class in archaeology was in spring quarter of 1967. The professor was a lean, fit man in his late thirties with thin blonde hair and a beard. He had great tales to tell. The class was taught in the MSU museum and there was a stuffed moose standing in the corner of the room. How cool can you get?

My roommate and I immediately started growing beards. I still have mine. In a miracle of convergence, I had a full beard about the time I saw them growing on faces all over campus. I had become a hippie, when all I wanted to do was look like Dr. Cleland.

It was an Indiana Jones moment, fourteen years before the movie came out.

I had escaped Oklahoma and had no intention of going back to spend my summers working on the farm. There are no summer jobs in social anthropology, but you an sign on to an archaeology crew, and I did for two summers.

1967 and 1968. Keep those numbers in mind. I was nineteen, then twenty. Keep those numbers in mind, too. Feminism was on the horizon, but I hadn’t heard of it yet. Political correctness, in those days, meant hating the Commies, supporting the Vietnam war, beating up hippies and draft dodgers, and voting Republican. I wasn’t politically correct.

The definition has changed since then, and I still am not.

Archaeology was an alpha male enterprise, in an alpha male era, and it was an alpha male time of my life. Sorry. Not bragging, not apologizing, just reporting.

Archaeology is hard, dirty work in the hot summer sun. It was much like what I left in Oklahoma, minus the manure but plus an intellectual content. I enjoyed it, but I didn’t fall in love with it. Like everything else in science, you spend a thousand hours of work for one tiny nugget of knowledge. The work didn’t bother me. Work is just work; I’ve always done it and I will as long as my body holds out. But there weren’t enough rewards.

My crew was doing survey archaeology all over northwestern lower Michigan. Our home base was Kalkaska just southwest of Traverse City. It’s a small town known for its giant fiberglass trout statue. The local young guys yelled insults at us when they saw us on the street. We were too cool (in our own minds) to be bothered. You know the drill. If there were any local young girls in town, they kept them well hidden.

We spent our days walking up and down the local rivers, looking for evidence of camp sites along the banks, or walking the shore of Lake Michigan for the same reason. Evidence of habitation meant chips of chert (the local low grade version of flint), pot sherds (broken pieces of pottery), or midden (trash heap) mounds. You had to learn to distinguish chips of worked stone from natural breakage while walking along at a normal pace.

If we found enough surface evidence, it was time to make a test pit. That meant a ten foot by ten foot square, taken down with flat bladed shovels in four inch lifts. All the dirt from each lift was tossed into a sieve — a wooden sided box with a 1/4 inch screen bottom. This was suspended from a sapling tripod and shaken. Dirt went through, chips, flakes, arrowheads, stone knives, or bits of pottery would be left behind.

Or, more often, nothing would be left behind and the test pit would be abandoned.

Sometimes we would be on public land, but most of the time we had to negotiate for permission to enter. The grad student who was leading our group spent more time making friends with local farmers — or trying to — than he did looking or digging.

So it went for most of two months and then everything changed for the better. It was about to get exciting. I’ll tell you about it Wednesday.

610. Time and Time Again

I love my jobs, both writing novels and blogging. Every new blog I write opens me up to new knowledge, often arriving in replies from the people who have read them.

Blogger and regular reader Thomas Anderson of Schlock Value replied to last Monday’s post on decimal time. I gave him a quick answer and then went looking for information because he referred to  Swatch Internet Time, and I had never heard of it.

Swatch Internet Time turns out to be a top down system, while the one the colonists of Sirius use is bottom up. No, I’m not talking about oligarchs and the people. Swatch Internet Time took the day and divided it into 1000 parts called beats. The Sirian system takes a second and builds up a system of terms from there. It turns out SIT was all about erasing borders, including time zones, to turn the internet into one endless, borderless day. It was more political (and marketing) than scientific.  After all, no matter what you call a time system, it is still daylight in India when it is night time here in California, and vice versa. Still, it’s a fascinating idea that I had missed out on.

Fascinating, but . . . there was already a universal time called  UTC, or Zulu, or military time, wherein you simply convert your local time to Greenwich Time, while pretending that Greenwich is never on Daylight Savings Time.

Further research showed that decimal time is a notion that has been tried occasionally, starting with the French about the time they adopted the metric system. It has never worked out, probably because we already have a system that works, irrational though it is. Our system won’t work so well once we are on planets with different day lengths and year lengths. It certainly wouldn’t be optimum in non-planetary colonies.

When the issue of decimal time originally came up for me, Swatch Internet Time didn’t exist. The internet didn’t exist either. It was, as nearly as I can calculate, about 1980, as a follow-on to several other things that had occurred in the particular universe I was writing about at the time.

I invented the Standard Year in Jandrax in 1976 with absolutely no thought, and had to flesh it out later in Cyan. It depended on the notion that Muslim countries would eventually refuse to let a Christian calendar stand for all mankind, so goodbye to BC and AD. The solution to that problem, in Cyan, was to reset year zero to October 12, 1492, the day that began the age of discovery which would finally knit the world into a whole. See 25. Columbus, King of Explorers. As part of the restructuring, months and weeks were dropped, and days were identified by the number of days since the beginning of the year, as in the opening words of Cyan:

From the Log of the Starship Darwin, en route to the Procyon system, S.Y. 594, Day 167

Cyan itself had a very long day and year, and it had no seasons. A Cyanian year meant little to the colonists, so people measured their ages by Earth years. The term day came to mean from sunup to sunup, and the human daily cycle of sleep and waking became known as a sleep.

Even these people, born on Earth and newly arrived on Cyan, had to make changes in the terminology of time. The colonists around Sirius would be refugees, fleeing the breakup of Earth after the Cyanian colonists departure, and living in space colonies. They made bigger changes. See last Monday.

These things occur by accretion in the real world, and also in writing. After I wrote last Monday’s post, but before any of you saw it, I had already had to add one more term, det, because my people needed a time unit longer than a dae to use in their everydae (not a misspelling) conversations.

Since then I have also come to realize that I have to also have to be able to put events into a deep framework.

On Earth, we would say something like February 12, 2019. On Cyan they use standard years and days for that, as in the quotation above. I decided that the colonists around Sirius would follow the standard year practice and set a certain dae as zero dae, then count forward. You could say:

Antrim was born on dae 348,278.

That is certainly clumsy for humans, but it is entirely suitable for computers which would be keeping all the records that far into a future world of ships and space stations.

To choose the zero dae, I will have to know how far in the future this story takes place. I haven’t decided yet, but once I figure that out, I’ll know how many daes ago they began to count time in daes.

There you go, simple. Clear as sunshine on a cloudless dae. Except in space, all daes are cloudless.