from HTYP, the free directory anyone can edit if they can prove to me that they're not a spambot
Revision as of 17:53, 3 August 2020 by Hkhenson (talk | contribs)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigation Jump to search

A story of Space Elevators and Power Satellites

plus a bit on Mining Asteroids

By Keith Henson

(Draft March 9, 2014 ~10,000 words)

June 2025

On the cavernous hangar deck of the former aircraft carrier Enterprise

Amid a maze of electrical cables, water, and sewer pipes, there were a hundred lashed-down house trailers. Mohawk-ironworker families from Ontario and upstate New York occupied most of them. Marc Leaf, his wife Minny, and their children lived in an outside trailer on the port side.

The Enterprise was anchored eleven miles south of Baker Island, in the Western Pacific doldrums. It was just inside the only territorial waters of the US that came within a few miles of the equator. The location made the UpLift suits happy though Marc could not imagine why. Nobody was going to attack the huge ship halfway between Hawaii and Australia. In Marc's opinion, the monotonous weather—no storms—was the reason.

The kids were in bed and Marc and Minny were at the rail holding hands and looking out at the equatorial ocean in bright moonlight. No matter how bright, moonlight scenes are black and white. Marc thought back to a silent hike he had made when a teenager in a light snowstorm under a full moon.

It had been just below freezing in the middle of the night. Marc, his brother, his father, his uncle, a cousin and his grandfather had walked several miles up Willow Creek. The cloud cover was thin; the full moon was bright on the fresh snow. The moonlight left pockets of pitch-black under trees and in the water. The effect was surreal, the beauty intense.

Dressed in warm boots and a military surplus jacket Marc had had no problem staying warm. There was no problem staying warm here. The only thing that kept it from being unbearably hot was a constant breeze from the east. The breeze blew through the hangar deck and carried away the heat from trailers' purring air conditioners.

Over the air conditioners, Marc felt the vibration of the 31-foot diameter driver wheels turning at 900 rpm. The whip-cracking sound of the supersonic space elevator cable reminded Marc of a flag flapping in a strong wind. There was vibration from an occasional run down and run up of the variable speed cable. The elevator was lifting parts now. Over its life, more than ninety percent of the capacity of the elevator had raised more cable and counterweight. Four more doublings would take it from its current capacity of 125 tons a day to its design capacity of 2,000 tons per day.

Baker Island was nearly invisible on the horizon but they could see the airstrip beacon. Practically everything going up the elevator except new cable came in by air. Helicopters shuttled loads over to the flight deck. New cable came in converted tanker ships. Between the Enterprise and the island, UpLift was installing pylons in the shallow water for a 6-km rectenna. This was for the first small-scale, solar-power- satellite power coming online in two months. At that point, the power available to run the elevator motors would go up to a full gigawatt. All the Enterprise's eight reactors could provide was a fifth of a GW.

Four generations of Marc's family had been "skywalkers" on high steel in New York City, Chicago, Pittsburgh. Marc's grandfather and great grandfather made an 8-hour commute from Akwesasne twice a week. Marc's father had moved his family to the Mohawk enclave in New York. Commute accidents in those days killed more than falling from high steel. Marc lived at one end of this job site and still faced a 22-hour commute to get to work.

"Going to miss you, Warrior," Minny said.

"Onkwehonwehnéha." By force of habit when he used Mohawk phrases, Marc repeated in English: "It's always been our way."

They stood at the rail looking out to the north. Men hunting or working far from home had been the way for the matrilineal tribe far back into history. In practical terms, the clan's women had more influence than the often-away men did. When women in the wider western culture became "liberated," they were just catching up with the "People of the Flint."

After a while, Marc groused, “This has got to be the worst commute in history.”

"Eleven more months and we can go up too."

"The boys will get a kick out of that, though they'll miss the beaches."

The ironworker families expected to move to geosynchronous orbit. That would happen as soon they pressurized and spun up the big habitat. UpLift didn't like the time-wasting and lift-wasting commute any more than the ironworkers did. Some of the engineering support staff would move with them.

Robbie, in kindergarten and their youngest, was particularly enthusiastic about going up. Jack was three and a half years older. He had no problem explaining that Coriolis forces separated the up and down strands of the space elevator. Marc wondered if access to zero-G would make up for the beaches at Howland, some 40 miles to the north.

Over the weekend, the family had been at Howland. They used the long wide beach on the lee side of the island. Marc and Minny shared the beach with a few dozen other families. Half of them were missing the men who were working their three-week shift in space.

The waves breaking over the reef on the windward side of the island had come a quarter of the way around the planet. The refracted waves passed over the west reef. They swept foaming up the wide beach among the giggling children, then hissed back, vanishing into the sand.

UpLift had negotiated the use of this magnificent beach with the Fish and Wildlife Service. In exchange, the company exterminated the rats on Howland. UpLift dropped a few miles of weighted plastic pipe ending a bottlebrush array of osmotic membranes to the west of Howland. The water there was close to 13,000 feet deep. That gave a pressure at depth of 5700 psi, much more than the 500 hundred psi needed to make freshwater. Freshwater is less dense than salt. That made the water rise in the pipe to within 400 feet of the surface. A submersible pump brought it up the rest of the way. If the ocean had been three times that deep near Howland, freshwater would have flowed all the way back to the surface under pressure.

The freshwater supplied showers next to the Porta-Potties every 50 meters down the beach. The only problem was the sea birds that flocked around the showers for a drink. The birds could drink seawater and excrete concentrated salt in tears but they much preferred freshwater if they could get it.

Marc and Minny sat under a cabaña drinking beer and talking to friends and relatives from the "trailer park." Floyd was a non-Mohawk project engineer who solved space construction problems from the ground. He was itching to go up and envied the ironworkers who had been going up for over a year. His wife, Kanati, was Minny's cousin and a midwife who team-taught kindergarten and first grade with Minny. She wasn't completely enthusiastic about moving to space, but their son Jason who was six was just as hyped up as Robbie was. All four of the adults had taken a hit from the "drunk" side of a Drunk and Sober bottle. That meant a couple of six-packs was all they needed to stay buzzed all afternoon.

After a hot-dog lunch, the kids went back to playing in the reef-attenuated surf. Kids younger than about ten didn't bother with swimsuits. Those entering puberty became shy about developing bodies and most wore suits. Among the adults, some wore suits and some didn't. Nina, Jason's 10-year-old sister, had just acquired a yellow bikini. It totaled about ten square inches. Wet and against her tanned skin, it was almost transparent. Jack would have teased her about it but she had a reach advantage on him at this age and he decided bruises were not worth it.

Minny and Kanati chatted in a mix of English and Mohawk while keeping an eye on the kids. The subject was when to get pregnant.

"I'd do it now, we could certainly afford another one, but taking a little one up . . . ." Kanati shock her head. "Be hard to take care of a baby that long in a medium-sized closet."

"I bet all of us try for the first baby born in space," Minny said softly. "The worst-case radiation on the way up isn't as bad as the polychlorinated Wahecmah our mothers got from their mothers eating contaminated fish." The contamination of local caught fish in the St. Lawrence River had been a contentious topic when Minny's mother was growing up.

Minny paused, looking at the kids. Kanati waded out and warned the older kids they were getting close to the sharp-as-knives coral heads. She didn't tell them to back off. It wasn't onkwehonwehnéha to order kids away from minor danger. The kids did put more distance between themselves and the coral.

"The Xylocaine spray is in the bag with the sunblock if a wave knocks them into the coral," Minny said as Kanati came back.

"I hope they don't need it. The Jacobs kid was a mess."

"That's why they're being careful. His scabs were a nine-day wonder."

Marc and Floyd who had been following their wives' conversation just looked at each other with a resigned look. They had read UpLift's advice that being pregnant when the families went up next year wasn't a good idea. There was the possibility of missing a station transfer and having to reenter. The advice sheet went on to suggest that the second trimester would be the least risky. That included possible solar flare radiation.

"Floyd?" Minny got his attention.


"How does it look for going up on schedule?"

"Not bad. We're about ten days ahead of schedule, but if something big hits the cable . . " He trailed off. Everyone knew that could delay UpLift months. It depended on where the cable broke and how well the recovery systems worked.

"How likely is that?"

"Not very. From the small damage to the cable we see, there is about one chance in fifteen of the cable breaking in the next year. That's a one in thirty chance for six months and one in sixty for three months. It might be a bit less because the nitrogen we dumped to kill the Van Allen belt is de-orbiting much of the little junk."

Minny and Kanati went into heads-down mode figuring when they should quit using birth control.

"I bet we could put in a beach." Floyd mused watching the kids. "Like those ones in California where they use air to pump up waves."

"Down a habitat axis or crosswise?" Marc asked. "Makes my head hurt trying to imagine what Coriolis would do to waves."

"We could hang it out, half g or whole g." ("Out" was the cable and counterweight hanging beyond GEO.) "God knows there will be enough water," Floyd replied. Most of the big push to build up the counterweight over the next year would be bringing up water. As Marc started to object, Floyd cut him off with, "Yeah, the travel time would be too much, bad as your commute."

The conversation drifted off into spearfishing around Baker. They expected it would be a lot better after UpLift put in the pylons for the local rectenna. Then:

"Kanati mentioned your brother Ricky got in some kind of trouble," Floyd said.

"Oh my God, did he." Marc shook his head. "My fool brother put the sound of racking a 12 gage pump shotgun on his cell phone as the ring tone. He was in a Pizza Hut line when the damned phone went off. The guy in front of him was undercover RCMP who some biker had threatened with a shotgun earlier that day."

"What happened"? Floyd asked.

"The Mountie tried to pull his gun and turn around. The gun went off, slug hit the floor, and bits of lead and floor chopped up a little kid's legs. Fortunately, it wasn't too bad. The cops arrested Ricky. They were asking for bail. Before I could wire the money, the tribal lawyer got him released. The lawyer talked to the Crown attorney. The Crown told the RCMP a charge of threatening an officer with a cell phone ring tone wouldn't fly."

Marc sighed. "At least he wasn't murdered by the cops like Leroy Shenandoah. My great uncle served in the Green Berets with him and grandfather was working with him in Philadelphia when that went down. Wish I could get Ricky to try for a job here, but his girlfriend won't consider it." Floyd commiserated on the time he had to bail out his brother and went on, "At least he wouldn't have to worry about nervous macho cops here."

One of the directors of UpLift held strong opinions about police, so the entire force was female.

Since most of the men on the project were married, there wasn't a lot of business for the company police. Drunk and Sober helped too. The Drunk drug blocked the enzymes that broke down alcohol. Sober unblocked them. It raised the enzymes' activity about ten times so that it only took fifteen minutes to metabolize the alcohol and sober up.

The tropical sun was less intense by late afternoon. Even so, nobody felt like recruiting enough people to play volleyball. An hour before dark those who had been drinking took a hit of Sober. All the families enjoying a day on the beach walked back to the chopper pad for the twenty-minute trip back to the deck of the Enterprise. (The chopper pad was just a 200-foot circle of canvas to keep sand out of the engines.)

Most of the families went below because the flight deck was noisy from elevator cables and driver wheels. Marc and Minny took their boys, Jason and Nana to the stern of the ship and watched the sun go down. The kids were trying to see the elusive green flash.

In the morning, Marc kissed Minny goodbye. Then he picked up his flight bag and took the stairs from the hangar deck down to the bilge of the Enterprise. Minny got the boys and herself off to school.

About half the thousand people who worked on the ship for UpLift were ex-Navy. Most of those had worked on "the Pig" when it was in service as a warship. Marc had asked how the ship gained its nickname. The former navy boys regaled him with stories of the huge ship in deep draft to get under the Golden Gate Bridge. It wallowed in the San Francisco Bay mud, the propellers throwing up great hunks of the bottom muck, and getting stuck.

“Ten minutes Marc. The down car will be at the transfer station in three minutes."

Traffic control liked to keep the load on the elevator constant. That was especially the case in the sensitive bottom segment. The down car would drop off the variable speed elevator cable four at thousand feet up. That was just after the cable decelerated the car from a thousand mph to four hundred in the upper atmosphere. At the same time, Marc's car was to latch on. With the size of the cable now in place, it wasn't as critical as it had been. The car coming down would dump its shielding water and descend by parachute.

Marc already had on his "pull up past the ears" hip waders on. He shuffled into the elevator car—no larger than a phone booth--and the techs hooked his waders to eyebolts in the ceiling. They poured tepid water into the waders up to his chin, and then checked the flexible plastic neck dam. “Stay dry, Marc” one of them joked to the immersed ironworker and closed the door. He was referring to the time several months previous when Marc's car had failed to hook the cable. After rocketing sideways to get it out of the way of the elevator cable, it had splashed down a few hundred yards from the ship.

It hadn’t happened yet, but one day a piece of space junk missed in the cleanup would cut the cable and dump a car from a couple of thousand kilometers up. Uplift engineers had designed the cars to survive a fall off an elevator. They would re-enter or go into a rescue orbit from any elevation, but Marc didn’t want to be the test case.

At thirty seconds, he got a countdown. At twenty seconds, he started hyperventilating. Then ten, nine, eight, seven, six, five, four, exhale hard to get as much air as he could out of his lungs. Three, two, Marc ducked his head underwater in the flexible plastic neck sleeve so he wouldn’t break his neck, one, SURGE.

The Enterprise’s steam catapult had launched twenty-ton aircraft to a hundred mph. Now it stretched nanotube cables like a bungee cord. Released, they hurled Marc’s one-ton car up a shaft cut all the way to the bilge. The car wet up the 200-foot latticework tower resting on the flight deck at twenty g. It cleared the tower going up at near the 400-mph speed of the variable speed elevator cable. (The high-g start increased the throughput of the space elevator. It reduced the speed cycling of the cable that lifted payloads the first fifty miles.)

As the car reached the top of the tower, the rolling clamp gripped the variable speed elevator cable at close to zero relative speed.

The g forces in the car went through zero, and up became down at about 0.1 g for a few milliseconds. Then the rolling clamp took up the weight and aerodynamic load and latched. This time, only a little water leaked past Marc's neck dam. The Pig's nuclear reactors poured more power into the drive motors, accelerating the cable and car to 500 mph. The car was now drawing 2,900 horsepower, of which 90% was going into raising the car’s altitude. The other 10% went into dragging the car’s aerodynamic body up through the atmosphere.

It would have taken much more power if Marc had been going up the thousand mph main cable instead of the VS cable. Almost three times more power needed to lift his car and excessively stressed the cable. This was due to the cube law of drag power and the doubling of the drag coefficient for going supersonic.

As the air thinned out above ten miles, the cable and car accelerated to the speed of the main cable. It was now drawing 6,000 horsepower, twice that of a railroad locomotive.

Seven minutes into his journey from the bilge of the Enterprise and fifty miles up, Marc’s car came to the transfer station. There was a moment of zero-g before the rolling clamp engaged the main cable on the far side of the transfer station. Marc had worked on the transfer station, adding sections to beef up the pulleys. You could get the FEAR there, in a full-g field and 50 miles up. Cameras and strain gauges watched the huge spinning pulleys at the transfer station. It was not a place for people. Unless you had to work on a pulley station, you didn't want the extra weight. This was especially that low on the cable where a pound added hundreds of tons of cable mass.

Anchored at a fixed elevation by the variable speed cable, the bottom pulley set didn't have active size control. The rest of the pulley stations stayed at elevation by active size control in their up- and down-pulley diameters. The first transfer station was low enough for space junk to burn up, so it didn't have the brakes and clamps to recover from a cut cable below it.

The requirements for working on the space elevator were simple. No fear of heights and no claustrophobia from a day cooped up in a closet. Marc had seen the next model of the car, the one his family would ride when they went up. It was about four times as big and folded out a little bit larger when you got out of the atmosphere. Going up on a thicker cable it didn't need the catapult, just slowing the variable speed cable to a near stop, latching on, and going up easy.

The shriek of atmospheric noise faded out. The ground controllers seemed to delight in telling Marc how far to the East from the he would land. They also chatted about the peak re-entry g forces if his car fell off the cable.

Marc couldn't keep from listening in spite of the number of times he had heard it,

"Eighty km, one km east, one km per sec re-entry, five g."

"Four hundred km, ten km east, two point five km/sec re-entry, twenty-two g"

"Eight hundred km, forty km east, three point six km/sec re-entry, forty one g."

Had his car missed the low transfer, it would have arced up for forty-five seconds. Then it would fall from almost ninety km. It would fall at a kilometer per sec, peaking out at five g and splashing down about a km to the east of the Enterprise.

Compared to the slingshot launch, that was a walk in the park.

Had the car come off at four hundred km, it was a different story. He would hit 2.5 km/second on re-entry, a peak twenty-two g deceleration, and splash ten km to the east.

At eight hundred km, it was 3.6 km/sec, a crushing forty-one g peak, and forty km to the east. Above that, if the kick motor didn't fire and put your car in a decent re-entry path, the car became your coffin.

Marc stayed wet and awake watching movies on his wall screen and an update on progress in the last three weeks. He reviewed what he would be doing in the next three weeks. Some people could sleep in water, but Marc wasn't one of them.

Minny called before putting the kids to bed and they chatted. Jack had Marc drop a pencil for the camera and managed to get his altitude correct to about ten percent.

The car finally reached an elevation and velocity where (with the aid of his kick motor) Marc would go into a rescue orbit. Above 23,000 km, the kick motor wasn't needed. In the much-reduced gravity, he unhooked his waders from the ceiling and spilled the water in them into the floor drain. This was something he had to do before the gravity went micro. The water was re-entry heat shielding and had been radiation shielding to get through the Van Allen Belt. Elevator cars dumping gas into the belts as they went up had mostly drained the Belt.

After almost four years of build-up from the first thread, the cable was lifting power-satellite parts. It had been lifting cable, pulley parts, and mass for the counterweight.

The function of the first SPS was to feed power to the cable from the bottom end. Once it came online, it would lift the heavy working cable. That would jump the elevator capacity over the next 9 months from a hundred twenty-five tons a day to 2,000 tons a day. Then UpLift could take reactors in the Enterprise, which had driving the cable, offline.

A hundred miles from geosynchronous orbit Marc's car turned around and switched to the braking cable. At a fraction of a g, it came to rest at "the junkyard" (known in the business plans as the "GEO complex"). This was a plane of light construction frames. It held materials for the elevator, the habitat, and the first power satellite (powersat). The original International Space Station had been here. They used it as living space for the first dozen ironworkers. Then the west junkyard and the first inflatable with room for 60 workers had been set up and filled. Now it was on its way out to the counterweight. There it would join the rest of the salvage. This included space junk pushed up to GEO by the ion-engine tugs and hundreds of tons of old communication satellites. Hubble was still in use, pushed up to GEO, and parked 170 degrees east of the construction site.

The junkyard attached to the space elevator through the so far misnamed "driver hubs," a pair of pulleys only a few miles apart. Uplift intended to install big electric motors, but the cable wasn't yet strong enough to lift motors that big in one piece yet. UpLift had attached the junkyard to the driver hubs with breakaway connections. This was in anticipation of the day natural or artificial space junk cut the cable. The four quadrants of the junkyard were minute flower petals on an impossibly long stem.

North and south petals of the junkyard held the local photovoltaic power sources. They were small-scale versions of power-satellite wings and rotated to stay pointed at the sun. The openings in the junkyard plane were much larger than the rotating "wings." UpLift planned to extend them to a GW when they installed motors on the driver pulleys.

There had been tension between building the elevator cable and the construction facilities. Now having reached the power limit of the Enterprise, construction of the first powersat was urgent.

In the three weeks since Marc had last been up, the second beam-spinner had come on line in the East junkyard. Uplift shipped up ton spools of perforated 5-mil Invar foil. After passing through the beam spinners, they came out as one meter by 1 km long channel beams. These were for the power satellites and the junkyard frame.

The same beams went into the frame for powersat construction--humorously known as "dry dock." It had gantries on both sides that hinged out of the way to launch the powersats to the east. The powersats slipped out of the dry dock by electric motors at 6 am local time when the transmitting antenna was in the same plane as the wings.

The little 60-person inflatable habitat was on the west petal. It pointed north/south with a 45-degree sun-tracking mirror to light it through a window on the north end. The space for the family habitat was just a large hole in the junkyard plane further west of the inflatable temporary habitat.

Dry dock was on the east side. It also pointed north/south. It rotated on bearings to stay pointing 90 degrees from the sun. There was a non-rotating section in the middle for the transmission antenna. The antenna pointed down the elevator toward the earth, parallel to the plane of the junkyard. The dry dock's daily rotation phased at 90 degrees from the sun was so the solar cells were "off" when installed. A powersat lacked a switch other than turning it away from the sun. Inflated white plastic balls on long skinny arms provided light for the construction crews. They didn't provide enough light to generate lethal voltage on the solar cell arrays.

The first powersat, Stubby, was taking shape as a 1/4 physical scale, 1/5th output power. It was to drive the elevator for the last stages of the cable buildup. Stubby would demonstrate the technology at almost full scale. Success would release the last of the investment money. Stubby had two wings like full-scale power sats, but the wings were only two km by three km instead of five by five km. That gave it a size of five and a half km by three km with a full scale one km round transmitting antenna in the middle.

The ironworkers installed the bearings, mercury slip rings, and transmitting antenna first. Then they built the two inner end pieces. Next, they pulled the beams out of the beam spinners. They did this from the outside in, stretched one at a time, spot-welded to the inner end pieces, then spot welded to the outer ends. They put the beams ten meters apart, a hundred beams to the kilometer so there were three hundred two-km long main beams in each wing. The ton mass of a 1-km beam amused Marc. In skyscraper construction, a meter of beam weighed more than a ton.

The construction process resulted in five flat-bottomed troughs in each wing. They connected to a rotating transmitter disk in the middle that always pointed toward the earth. The troughs were 600 meters wide, 280 meters high, with 45-degree reflector sides. Each had bottom had a 200-meter-wide pavement of solar cells. The cells came in rolls, two meters wide and 200 meters long. The reflectors raised light exposure on the cells to three solars. A square meter of solar cells generated 100 volts, 200 of these in series amounted to 20,000 volts across 200 meters. Five such strips in series generated 100,000 volts at a scary 10,000 amps from each wing.

Twenty thousand 100-kW input klystrons made up the one km antenna. They came up in hexagonal bundles of seven and snapped into place. Two ironworkers could put in a hundred a day. There would be 19 to a bundle when UpLift upgraded the elevator to 2,000 tons a day.

The plans had called for two km long, aluminized-Mylar reflecting film on the reflectors. The intent had been to test the completed power sat in dry dock at full power, then cut it loose with many ion engines to move it into place.

Vacuum degradation around the junkyard turned out to be worse than expected. There had been major flashover and meltdown on the junkyard's north power wing. This had the engineers antsy about powering up a powersat in the construction frame. To improve the hardness of the local vacuum, the engineers decided to ship up uncoated Mylar film. As it unrolled, they coated the film with aluminum. There is nothing like a fresh vaporized aluminum surface to absorb stray gas molecules.

Dry dock's first long compression members had been a major pain to make out of metal rolls. The ironworkers pulled the curved beams between the elevator's unpowered local drive wheels. This stretched the beams a few percent. That made them straight as a string, but it was hard to get the twist out. The ironworkers chopped up the first half dozen and used them to extend the junkyard.

After some fast design work by UpLift's engineers, they put real-time controls on the rollers in the beam spinners. They put a laser target on the end of the beam to detect twisting. As the beam spinners bent the flat sheet into channel beams they were able to compensate for twisting. After post-stretching, all the beams since then had come out in spec for powersats. Most of them were good enough to carry the dry dock's compressive load. The ironworkers got busy stretching powersat channel beams.

Marc's main job this shift was to move the beam spinners along the start end in the construction frame. The frame was only three-fifths of its final width and half its length. When completed and producing full-sized powersats, the plans called for four beam spinners.

The target construction rate was a powersat every five days. That depended on the elevator reaching full capacity, and that in turn depended on this first quarter scale sat to power it. Full-scale powersats would mass twenty-five thousand tons. Stubby was only a quarter that mass and bringing up its parts had occupied the elevator for over a month. It had taken another forty days to bring up the parts for the quarter-sized dry dock needed to assemble it.

When the rolls of beam stock first started coming up, Marc asked Floyd why they were using this expensive nickel alloy, not steel or aluminum.

"Eclipses," Floyd told him. "For a few weeks around the equinox, an SPS gets eclipsed by the arth, for up to 70 minutes. The darn things cool by 200 degrees. Steel or aluminum would curl up like a potato chip. Then when the Sun comes back, they flap like wings. The computer simulations were sad. We could put hinges and dampers into them, but using Invar, we can just ignore eclipses. The temperature coefficient is near zero"

There were only 60 people at the construction yard. They were critical for building and unjamming the automation. The speed-of-light delay made it hard to do most jobs from the ground.

It was amazing how much you could get done in zero-g riding around on a magnified version of the ancient shuttle arm. In spite of having to move the beam spinners around, by the end of Marc's three weeks they were a quarter done with framing Stubby. They had pulled out half the beams on the north wing. Four more beam spinners had come up, so the next quarter would take only half as long.

October 2025

Three months later, just before Marc's 21st trip up, the families were back at the beach on Howland drinking beer.

UpLift launched Stubby in late July and moved it off fifty km to the east. There had been a few flashovers. They required instantly shorting the ten-thousand-amp output from a wing before the conductors vaporized. Recovery required turning the wings away from the Sun. They turned one CCW and the other CW. The workers had to inspect and repair the short. The wings turned back toward the sun, taking the powersat offline for hours. After a few of these, the vacuum around Stubby had cleaned up and there had been no more problems in the last month. Power for the elevator motors was now coming from the rectenna via a thick submarine cable. The Enterprise's reactors were still on hot standby.

During the nights around the autumnal equinox, UpLift had unloaded and slowed the elevator. Unloaded, the Enterprise could power the elevator when Stubby went into eclipse. The elevator was back to lifting more cable, though the ironworkers were getting some beam spools. They used these to extend the dry dock. They also got early lead items such as the bearings for the family habitat--now only 6 months from completion. They would have to do the same for the vernal equinox in March. By the following autumnal equinox, they should be able to borrow power from a full-sized powersat an hour to the east or west. On one of their beach outings, Floyd asked.

"How's your brother doing, Marc?"

"Much better. He and his girlfriend broke up. Ricky took a dose of one of the emo reset drugs to get over her. I think it was the one called Red Rubber Ball after an old song."

"Then he talked to UpLift's HR about working at the junkyard. They don't want unattached ironworkers. So they introduced him to a young woman from the Six Nations reserve near Brantford. She wanted to go into space and had complimentary MHC genes." He grinned, "It was love at first sniff. They're getting married next week!"

Floyd nodded. "It's just amazing how much difference smell makes in stable couples."

Kanati grinned at Floyd. "About a 70% reduction in the divorce rate. We tested before we got married, but I knew we were complimentary because he smelled good."

"So is Ricky coming out here?" Floyd asked

"Hah. Even if he does smell right to her, she will dump him if he doesn't. From what he said, she's a real space nut."

June 2026

The final-for-now cable was in place; the families had been up for a month. With a lot of ceremony, UpLift pushed the first full-scale powersat out of the enlarged dry dock. It had taken 13 days to construct and paid back its lift energy in two days. The next one took half that time to construct.:

None of the wives had come up in the third trimester. The news organizations pestered UpLift about when the first baby would be born. UpLift told them that if the parents wanted to announce it, they would hear about it in due time. To spread out the burden, the first five women announced simultaneous births.

Because the women were so busy, the social order had reverted to the longhouse style. That had gone out of style more than a hundred years ago. Some of them were working part-time with their husbands. Jobs in suits sometimes required physical strength. Most jobs were operating remotes and that took a delicate touch. The rest of the women were trying to fix up the bare habitat and put in a garden. The hundred and fifty families had split into three "tribal" groups. The social order was "ruled" by the oldest women and spaced eight hours apart. Childcare and cooking had become communal activities. This probably would not last, but for now, there were a hundred adults and about the same number of children eating cafeteria-style. After dinner, the adults were drinking microbrewery beer and watching a large screen TV.

There was a news segment about UpLift's turning on the first production powersat. The news story estimated the revenue at four billion dollars a year per satellite. The next story was about low lying countries petitioning the UN to use force majeure against UpLift. They wanted to divert UpLift's capacity to GEO into building L1 sunshades. In theory that would stop the ice melting before the rising sea swamped them.

When the story ended, Floyd looked disgusted, so Marc raised an eyebrow.

"Idiots." Floyd fumed. "Years ago UpLift offered to build elevator capacity for anyone who wanted to build sunshades. There were no takers. Now with the company on the brink of making money they want to grab our lift capacity."

"Think they might do it?" Kanati asked.

"Not a chance," Floyd replied. "UpLift was careful not to invest in any of the tools to build sunshades. The lawyers, backed up by engineering staff, can tell them to go piss up a rope."

"I didn't think basing the anchor ship in US territory was important, but seems to have been a good idea. They might be able to force us if the anchor was in international waters."

June 2027

What a difference a year makes!

Minny turned out to be wrong. Only about half the women tried to get pregnant before they came up or in the first few months. There were only 33 babies born in the first year. After the first five, media interest faded. They would constitute the first kindergarten class born in space in a few years.

Instead of 60 5-GW powersats, UpLift churned out 90, and the last 50 of those were 7-10 GW. They were the same physical size, upping the efficiency of the photovoltaic cells and the power of the klystrons. UpLift sped up the elevator cable as much as they could and cut into the cable safety factor to lift the extra parts. The engineers reduced powersats mass by 15 percent. The engineers wanted to shut down the elevator and reorganize it. The idea was to gear up the mechanical power from the ground and shorten travel time. The accountants opposed them because it would put a gap in power-sat construction. That would cost hundreds of billions.

The higher than expected power-sat production caused a rush on the ground to build more rectennas. Coal consumption was going down, almost three percent, and most of the powersats had been online less than a full year.

There had been a huge argument about the US meeting the demands for carbon reduction by selling powersats to the Chinese. They were able to avoid building dozens of coal plants. UpLift argued that it was one atmosphere and it didn't matter where you took out the CO2 sources, the US should get the credit.

It finally went to a court case. A federal judge looked at the production-rate trends and agreed to delay the case for a year. UpLift's lawyers were happy since it would be a non-issue in a year with the number of powersats dedicated to the US market. (The quality of legal judgments had gone up in the last few years. Judges were not supposed to take drugs that enhanced rational thinking. Nor were they supposed use rational analysis programs to help them, but it was clear they were doing so.)

Some of the out-of-work coal miners went into rectenna construction. Others were in Antarctica drilling holes in the glaciers. They were installing thermal diodes to slow down melting. Oil prices were steady, though the prospect of synthetic oil was depressing long-term futures. The Canada tar-sands companies were putting in a multi-GW electrolysis plant. It used off-peak power to make the huge amount of hydrogen they used to upgrade tar to transportation fuels. ExxonMobil was talking to UpLift about an initial order of 100 GW. They wanted it to power a prototype synthetic transportation fuel plant. ExxonMobil wanted to hydrogenate coal for transport fuels. Critics insisted they use biomass; extreme critics wanted them to take CO2 out of the air. The engineers quietly told management that they should go with CO2. In a few years of falling power prices, it would be less expensive to make gasoline, diesel, and jet fuel from CO2 than from coal.

Russia had mixed feelings about powersats. The demand for nickel to make Invar had gone through the roof and, being the largest producer, they were doing well. Still, the anticipated demand for their oil and gas falling, and they had bought only one powersat.

There had been a close call for the elevator cable. A small piece of space junk had hit the cable and cut about a quarter of it. Had the cable been stopped at the time, the hit would have severed it, but the damage was spread out because of the cable's motion. UpLift stopped the damaged section at GEO and repaired it. Load-control computers had dumped a dozen 6-ton Invar spools into the ocean. Then they determined the detected flash was due to be a non-fatal partial cut.

UpLift engineers finally figured out a way to carry up the next-to-last (half strength) cable. They sent it up on a series of double-sided clamps. The Junkyard crew stored it in a huge frame hung a bit beyond GEO as a backup.

January 2028

A premature 25-kiloton nuclear explosion destroyed a container ship a few miles off the east coast of the US. Investigators traced the incredibly high-purity plutonium 239 used to make the bomb to corrupted staff at a power reactor in a "friendly" country.

Marc and Minny were again eating pizza, visiting with Floyd, Kanati, Ricky, Susan and their new baby. Minny and Kanati were nursing each other's babies. They did it often enough that the babies were not surprised by the change in flavor. Marc, Floyd, and Ricky found themselves ignored as the women fussed over the babies.

"How did they make that bomb? Marc asked Floyd.

"It has been known for ages that you could run a U-238 solution through a reactor core. You can make near pure plutonium 239 by picking the plutonium out of the solution as it forms with ion exchange." Floyd paused to think then went on, "Twenty-five years ago the North Koreans built a bomb that didn't work very well. The reason is that they used plutonium extracted from a power reactor."

"How is that plutonium different?" Ricky asked.

"Most of the uranium in a power reactor is U-238. It doesn't fission until it picks up an extra neutron and turns into plutonium 239. The problem is that plutonium 239 doesn't always fission when it absorbs another neutron. Sometimes it becomes plutonium 240. Plutonium 240 fissions randomly, spitting out neutrons, which causes the bomb to go off before it should."

"Is that what happened off Newport?"

"No, by 'before it should,' I mean while someone is trying to make it go off as a bomb. It still makes a mess, but low yield, a small fraction of what it could do."

"Then how come it went off on that container ship?"

"I doubt we'll ever know. There was speculation that it was pure enough plutonium to have been a gun-type bomb design. Those are supposed to be more prone to going off accidentally, though I don't know why."

The response to this close call was a UN mandate to shut down all nuclear power reactors in the world. The UN decided that kilogram sources of neutrons were too dangerous to tolerate. Powersats could provide baseload power. The French, most dependent on nuclear power, were unhappy as only the French can be. Replacement power at a cost well below the cost of operating their breeder reactors brought them around. They agreed the reactors were to go into cold shutdown as soon as possible. In the meantime, all the reactors in the world were getting careful inspections for unexplained pipes into the core. Depleted uranium, widely scattered in wars, became a major hazard.

UpLift had already been building twenty-GW powersats to save orbital slots. Now they were considering jumping to fifty- or even sixty-GW powersats. They would have two transmitters in the middle and one on the north and south edges. Replacing all the nuclear power would take a hundred twenty-GW powersats. It would take 5,000 GW needed to replace the remaining coal and 10,000 GW for synthetic fuel plants. Governments pressured UpLift into putting in a second elevator. It was something they didn't want to do. One elevator failing could take out the other one from falling pieces of cable along the equator. However, there just wasn't room around Baker Island to put in more elevator power.

There had been a huge controversy about where to put the second anchor. Various countries along the equator offered locations. None had the favorable weather of the mid-Pacific. For political and business reasons, UpLift didn't want to put an anchor point outside of US territory. There just wasn't any as close to the equator as Baker Island. The engineers and company officials finally decided that ten miles south of the equator would work. That allowed anchoring the Nimitz twelve miles north of Jarvis Island (in US territory). The original habitat became Baker Hab with the new one named Jarvis Hab.

Jarvis Island had a shallow area of water to the east where UpLift could install a rectenna to power the new elevator.

UpLift pushed the spare half-strength cable, a set of pulleys, and a counterweight east. Ion tugs pushed the parts east to 160 degrees from the junkyard at 174 degrees. The half-strength cable allowed the new location to be productive at once. That was unlike the elevator at Baker where it took several years to raise stronger and stronger cable. They fitted the recently mothballed Nimitz with a duplicate set of driver wheels and motors. They installed them on a turntable identical to the one on the Enterprise. It was getting few other modifications. Its nuclear reactors were not large enough to raise a full-strength cable or lift 2,500 tons a day. The second elevator would increase UpLift's capacity to 5,000 tons per day, enough to build a 10-GW powersat every two days.

The Enterprise had taken years to convince the US government to lease it. The government practically forced the Nimitz on UpLift.

Corporate taxes on UpLift were going a long way to solve the balance of payments and Social Security's payout problems. Conspiracy nuts spread rumors that UpLift planted the bomb to get the reactor share of power plants. That was in spite of finding the fanatical group that had built the bomb. It annoyed UpLift that the government uprooted their carefully planned building program.

Lifting all the extra materials to duplicate the construction yard cost UpLift several powersats this year. But in a year and a half, the production rate would double.

Nickel for Invar was becoming a serious problem. It promised to get much worse when the power-sat production rate doubled. UpLift's business plan did not include "extraterrestrial materials." In hindsight, it was clear they should have gone after asteroid nickel-iron. UpLift, was now the most profitable company in the world. They decided to dedicate one powersat mass, and a dozen of the biggest ion engine tugs, to an asteroid mining project. The target was 1986 DA, a two-cubic-km chunk of nickel-iron.

If the powersat market saturated and UpLift didn't need it, they could sell nickel after being the biggest buyer for a decade.

Ove night Frank, Marc, Minny, Kanati, Ricky, and his wife Susan, and all the kids were eating tacos and drinking beer. Frank complained, "The new elevator is going to cut the time we have left to build powersats from 10 years down to 6 or 7."

"Six years or ten, who cares?" Minny commented, "We are already rich enough to retire on stock alone."

"Do you want to go back?" Kanati asked.

There was a moment of silence by all six adults then the four older kids broke in with a resounding "No!" They quieted down after reassurance that moving back to Earth was years off if ever.

"It would be nice to visit relatives in person rather than virtual more often," Susan said. "But for a place to live, this is hard to beat. And it will be even nicer when you finish the beach."

"We could put in for the mining project," Marc said. That generated a long silence from the adults and a milder buzz from the children.

Floyd spoke up, "We don't have to decide for a while. But the rumor is that for those who do to sign up, UpLift will pay 90% of the cost for telomere rejuvenation." That generated an even longer silence from the adults and puzzlement from the kids.

After a while, Floyd explained telomere rejuvenation to the puzzled children. It wasn't easy, Jack and Nina now 14 and 15, had just enough biology to understand it. Robbie and Jason at ten didn't get it.

"The bottom line is that you can take a lot more radiation.” Floyd looked thoughtful. “It also might add decades to our life spans.”

June 2033

UpLift had enforced a 20-day earth vacation on those who signed up to be asteroid miners before they left in late 2028. Marc and Floyd had taken the kids canoe camping close to the US/Canadian border. None of the kids had appreciated nature (too many bugs!) or being away from their zero-g playground and the recently finished beach with pumped waves. During the 20-day vacation, work stopped on powersats while the parts for the nickel extraction plant occupied the cable. UpLift's accountants hated the interruption in construction. However, they loved getting a replacement source for nickel. When the mine and processing plant came online, its production of 1000 tons of nickel per day would payback lifting the mass in 50 days.

The workers built a new habitat at the junkyard over Baker Island. Then they cut the original one (still spinning) loose of the junkyard. They attached it to a mini junkyard frame in place of a transmitter on a brand new 20 GW powersat. The ungainly looking processing plant became known as Camp Nickel. It was then “lowered” outward 1970 km down the counterweight cable. They moved part of the counterweight mass toward the junkyard to keep the cable tension in balance. Released at the proper time, the extra distance gave 140 m/sec to the mining camp. That was most of the orbital injection velocity to match with the solid metal asteroid. Ion engines coped with plane change and orbital matching.

Mining and refining equipment included, the processing plant and habitat massed 50,000 tons. That included 3,000 tons of reaction mass for the big ion engines. That far out on the counterweight cable the centripetal minus the gravity force was 30 N/tonne. One g being 9800 N/t, this amounted to 0.3% of a g. It hardly shifted the water at the beach. Still, 1.5 million Newtons is equal to the force on a cable holding up a 150 ton locomotive on the surface of the earth. The engineers worried about the superconducting thrust bearing on the habitat. It turned out that if they loaded it with liquid helium rather liquid nitrogen it had plenty of capacity for the 5000-ton habitat.

The elevator dynamics group schemed up a plan to have a large mass brake to a stop further down the counterweight cable. They did that just as the mining camp released. It worked well enough that the extra strain due to the release was well under the safety factor for the cable. There was a slosh of a few feet at the beach when the mining camp let go of the cable.

In the last three years, the processing plant at Camp Nickel had melted 10 million tons of 1986 DA. They had shipped a million tons of nickel in Invar. At this rate, it would take 60,000 years to use up the asteroid. UpLift was planning to increase the production in stages to six times the current mining rate. That became practical when mining had whittled the asteroid down to a sphere.

Four years after they left, there were 36 in Jack and Nina's graduating class, and 40 in the junior class. Their big spinning habitat had a beach but it was still a closed habitat. There just wasn't any way to get away from the drama of forming and breaking up teenage relationships. Half had entered the class after Jack and Nina (along with their families) moved with Camp Nickel. They had started to the asteroid during their last year of middle school. The new kids were children of the staff UpLift had sent out. They caused a continual reshuffling of relations. Dr. Scott handed out emotional reset pills as freely as he did birth control pills. Finally, he hit on testing all the high school kids for MHC genes and put them on a database open to the students. It didn't reduce the drama as much as he had hoped.

When Nina went in for birth control, she asked how Jack would work out for her.

"Nina, you and Jack are far enough apart in MHC genes to be a good match in spite of him being your second cousin." Dr. Scott paused, "but I wonder about the Westermarck effect."

Nina had already looked it up so she replied: "We only met a few times when we were very young. We started hanging out together when he was nine and I was ten and our parents moved to the Enterprise. We and a few other kids explored the escape ladders in the ship." Nina didn't mention the room full of porn including an ancient VCR that they found in a room near the middle of one of the ladders. It was compliments of sailors a generation ago.

"Well, you have given it some thought I see." With only 900 people, he dispensed as well as prescribed and was in charge of much of the environment management as well. Nina asked for a set of dilators and some lubricant. He gave them to her and let her go with a final warning.

"Nina, our minds are not tuned to having sex for years without babies." Dr. Scott gathered his thought before he went on. "If you had sex for a couple of years back in the Stone Age and didn't have kids, psychological mechanisms turned on in you. Most of the time, they caused you to break up with your partner. Chances were one or the other of you was sterile and it was better for your genes to try with another partner. There used to be a good reason to put off having sex with someone you like a lot until you are close to wanting kids." Nina nodded to Dr. Scott; this was familiar to her.

"I know. But now there are drugs that keep the breakup mechanism from turning on," She said.

"She will make a hell of a good doctor," he thought.

The class wanted graduation at their beach. The usually indulgent parents talked them out of it in favor of the multipurpose room that was also the cafeteria. So for the after-graduation party, the kids planned a Hawaiian luau at their beach. They wore their beach attire under the nice graduation robes UpLift had sent out. No families with older kids had joined in the initial migration so they were in the first class at Camp Nickel High School. A few of the families that moved out later left high school age kids with relatives or even family friends. Friends are sometimes more important than family to kids at that age. The mining venture had been so profitable that UpLift expanded it. The original core group of three hundred went to nine hundred. That was almost as many as the original habitat had held when attached to the junkyard over Baker Island.

Jack and Nina regained friends left behind when Camp Nickel was cut loose of the junkyard late in 2028. There was no choice about the date because asteroid 1986 DA swung closest to earth's orbit in 2028. Anything more than a minimum energy Hohmann transfer orbit would have been too expensive. There was a lot of mass in the processing plant, the twenty GW power plant, and the habitat. Both they and their friends left at GEO had become better than average at the old skill of writing letters. The mining camp was too far away for phone conversations to work. The asteroid swung out further than Mars taking a little over four and a half years to come back to 1.1 AU.

The mining camp was also too far away for casual visits. None of the Marc's or Floyd's family had been back to earth since they moved Camp Nickel out to 1986 DA. That would change by fall since Jack and Nina were going to college on earth. Jack wasn't entirely sure he wanted higher education. “Spacewalker” (suits or remotes) paid better than most professional jobs on earth. He had been working informally since he was 13 and part-time since he was 14. (Jack had enough on the books from working for UpLift to pay for the most expensive education in the world.) His uncle Floyd was the deciding factor so he was going to give becoming a professional space engineer a try. Jack didn't need them, but his SAT scores were good enough to get him into MIT. That was the result of small classes and the plant engineers teaching the math and science classes. There was also the effect of living in space. There science and engineering were all that kept you alive, not to mention well-fed and amused.

Nina was dead set on becoming a doctor/midwife. Both Boston College and Harvard wanted her. She was dithering about which to accept but near MIT was required since she intended on living with Jack. Typical of Mohawk culture, Jack went along with the idea.

Uplift paid for the education of their workers out of the “gold fund.” The asteroid was about 1 ppm gold. The gold had come out of the refining stream, about 10 tons of it. Gold prices were declining in the economic boom from cheap energy. Still, gold was still over $10,000 a kg, so there was embarrassing excess in the fund. It wasn't easy to get rid of it. The universities wanted "space kids" for "diversity." They want them so bad that they offered them full scholarships to any who applied. UpLift quietly donated compensating funds to the universities that took children of their workers.

Jack and Nina fully intended to go back into space, as did most of their classmates. (Unlike small towns in the previous century, there was a vibrant growing economy where they went to high school.)