## Monday, July 29, 2019

### New: Units Calculator

Units Calculator is a Web interface to the GNU Units utility which allows conversion among thousands of physical units, constants, and currencies. Units Calculator may be used to perform complex scientific and engineering calculations involving physical units and guards against common errors due to dimensional incompatibility. Units Calculator is 100% compatible with GNU Units, but as a Web application can be used from any platform with a Web browser. Currency exchange rates and precious metal prices are updated daily. See the Introduction for a tutorial, or proceed directly to the Expert page, which contains a click-to-copy table of common units.

Units Calculator can be used as a simple units conversion tool, but is much more powerful than that. Suppose you wish to calculate the power emitted as gravitational radiation as the Earth orbits the Sun. This is given by the following equation, where G is the Newtonian gravitational constant, c is the speed of light, R is the radius of the orbit (which we'll assume here to be circular), and m₁ and m₂ are the masses of the two bodies. (You don't often see an equation in physics with an exponent greater than three, but this one has two fives and a four, and that's the fifth power of the speed of light in the denominator!)

Since Units Calculator already “knows” all of the quantities which figure in this equation, we can immediately calculate as follows.

Convert To ((32 G^4)/(5 c^5 astronomicalunit^5)) ((sunmass earthmass)^2) (sunmass + earthmass) watt ((32 G^4)/(5 c^5 astronomicalunit^5)) ((sunmass earthmass)^2) (sunmass + earthmass) = 196.27068 watt

So, around 200 watts!

Units Calculator supports, as of this writing, 3460 linear units, 109 nonlinear units, and 109 prefixes, plus 171 currencies and 3 precious metal (gold, silver, and platinum) prices. See the Unit Definition database (taken directly from the GNU Units utility) for a complete list.

Posted at 13:50

## Monday, July 22, 2019

### Reading List: Island of Clouds

Brennan, Gerald. Island of Clouds. Chicago: Tortoise Books, 2017. ISBN 978-0-9860922-9-9.
This is the third book, and the first full-length novel, in the author's “Altered Space” series of alternative histories of the cold war space race. Each stand-alone story explores a space mission which did not take place, but could have, given the technology and political circumstances at the time. The first, Zero Phase (October 2016), asks what might have happened had Apollo 13's service module oxygen tank waited to explode until after the lunar module had landed on the Moon. The present book describes a manned Venus fly-by mission performed in 1972 using modified Apollo hardware launched by a single Saturn V.

“But, wait…”, you exclaim, ”that's crazy!” Why would you put a crew of three at risk for a mission lasting a full year for just a few minutes of close-range fly-by of a planet whose surface is completely obscured by thick clouds? Far from Earth, any failure of their life support systems, spacecraft systems, a medical emergency, or any number of other mishaps could kill them; they'd be racking up a radiation dose from cosmic rays and solar particle emissions every day in the mission; and the inexorable laws of orbital mechanics would provide them no option to come home early if something went wrong.

Well, crazy it may have been, but in the mid-1960s, precisely such a mission was the subject of serious study by NASA and its contractors as a part of the Apollo Applications Program planned to follow the Apollo lunar landings. Here is a detailed study of a manned Venus flyby [PDF] by NASA contractor Bellcomm, Inc. from February 1967. In addition to observing Venus during the brief fly-by, the astronauts would deploy multiple robotic probes which would explore the atmosphere and surface of Venus and relay their findings either via the manned spacecraft or directly to Earth.

It was still crazy. For a tiny fraction of the cost of a Saturn V, Apollo spacecraft, and all the modifications and new development to support such a long-term mission, and at no risk to humans, an armada of robotic probes could have been launched on smaller, far less expensive rockets such as Delta, Atlas, and Titan, which would have returned all of the science proposed for the manned fly-by and more. But in the mid-sixties, with NASA's budget reaching 4% of all federal spending, a level by that metric eight times higher than in recent years, NASA was “feeling its oats” and planning as if the good times were just going to roll on forever.

In this novel, they did. After his re-election in 1968, where Richard Nixon and George Wallace split the opposition vote, and the triumphant Moon landing by Ed White and Buzz Aldrin, President Johnson opts to keep the momentum of Apollo going and uses his legendary skills in getting what he wants from Congress to secure the funds for a Venus fly-by in 1972. Deke Slayton chooses his best friend, just back from the Moon, Alan Shepard, to command the mission, with the second man on the Moon Buzz Aldrin and astronaut-medical doctor Joe Kerwin filling out the crew. Aldrin is sorely disappointed at not being given command, but accepts the assignment for the adventure and opportunity to get back into the game after the post flight let-down of returning from the Moon to a desk job.

The mission in the novel is largely based upon the NASA plans from the 1960s with a few modifications to simplify the story (for example, the plan to re-fit the empty third stage of the Saturn V booster as living quarters for the journey, as was also considered in planning for Skylab, is replaced here by a newly-developed habitation module launched by the Saturn V in place of the lunar module). There are lots of other little departures from the timeline in our reality, many just to remind the reader that this is a parallel universe.

After the mission gets underway, a number of challenges confront the crew: the mission hardware, space environment, one other, and the folks back on Earth. The growing communication delay as the distance increases from Earth poses difficulties no manned spaceflight crew have had to deal with before. And then, one of those things that can happen in space (and could have occurred on any of the Apollo lunar missions) happens, and the crew is confronted by existential problems on multiple fronts, must make difficult and unpleasant decisions, and draw on their own resources and ingenuity and courage to survive.

This is a completely plausible story which, had a few things gone the other way, could have happened in the 1970s. The story is narrated by Buzz Aldrin, which kind of lets you know at least he got back from the mission. The characters are believable, consistent with what we know of their counterparts in our reality, and behave as you'd expect from such consummate professionals under stress. I have to say, however, as somebody who has occasionally committed science fiction, that I would be uncomfortable writing a story in which characters based upon and bearing the names of those of people in the real world, two of whom are alive at this writing, have their characters and personal lives bared to the extent they are in this fiction. In the first book in the series, Zero Phase, Apollo 13 commander James Lovell, whose fictional incarnation narrates the story, read and endorsed the manuscript before publication. I was hoping to find a similar note in this novel, but it wasn't there. These are public figures, and there's nothing unethical or improper about having figures based upon them in an alternative history narrative behaving as the author wishes, and the story works very well. I'm just saying I wouldn't have done it that way without clearing it with the individuals involved.

The Kindle edition is free to Kindle Unlimited subscribers.

Posted at 22:07

## Friday, July 19, 2019

### Reading List: What Has Government Done to Our Money?

Rothbard, Murray. What Has Government Done to Our Money? Auburn, AL: Ludwig von Mises Institute, [1963, 1985, 1990, 2010] 2015. ISBN 978-1-61016-645-4.
This slim book (just 119 pages of main text in this edition) was originally published in 1963 when the almighty gold-backed United States dollar was beginning to crack up under the pressure of relentless deficit spending and money printing by the Federal Reserve. Two years later, as the crumbling of the edifice accelerated, amidst a miasma of bafflegab about fantasies such as a “silver shortage” by Keynesian economists and other charlatans, the Coinage Act of 1965 would eliminate sliver from most U.S. coins, replacing them with counterfeit slugs craftily designed to fool vending machines into accepting them. (The little-used half dollar had its silver content reduced from 90% to 40%, and would be silverless after 1970.) In 1968, the U.S. Treasury would default upon its obligation to redeem paper silver certificates in silver coin or bullion, breaking the link between the U.S. currency and precious metal entirely.

All of this was precisely foreseen in this clear-as-light exposition of monetary theory and forty centuries of government folly by libertarian thinker and Austrian School economist Murray Rothbard. He explains the origin of money as societies progress from barter to indirect exchange, why most (but not all) cultures have settled on precious metals such as gold and silver as a medium of intermediate exchange (they do not deteriorate over time, can be subdivided into arbitrarily small units, and are relatively easy to check for authenticity). He then describes the sorry progression by which those in authority seize control over this free money and use it to fleece their subjects. First, they establish a monopoly over the ability to coin money, banning private mints and the use of any money other than their own coins (usually adorned with a graven image of some tyrant or another). They give this coin and its subdivisions a name, such as “dollar”, “franc”, “mark” or some such, which is originally defined as a unit of mass of some precious metal (for example, the U.S. dollar, prior to its debasement, was defined as 23.2 grains [1.5033 grams, or about 1/20 troy ounce] of pure gold). (Rothbard, as an economist rather than a physicist, and one working in English customary units, confuses mass with weight throughout the book. They aren't the same thing, and the quantity of gold in a coin doesn't vary depending on whether you weigh it at the North Pole or the summit of Chimborazo.)

Next, the rulers separate the concept of the unit of money from the mass of precious metal which it originally defined. A key tool in this are legal tender laws which require all debts to be settled in the state-defined monetary unit. This opens the door to debasement of the currency: replacing coins bearing the same unit of money with replacements containing less precious metal. In ancient Rome, the denarius originally contained around 4.5 grams of pure silver. By the third century A.D., its silver content had been reduced to about 2%, and was intrinsically almost worthless. Of course, people aren't stupid, and when the new debased coins show up, they will save the old, more valuable ones, and spend the new phoney money. This phenomenon is called “Gresham's law”, by which bad money chases out good. But this is entirely the result of a coercive government requiring its subjects to honour a monetary unit which it has arbitrarily reduced in intrinsic value.

This racket has been going on since antiquity, but as the centuries have passed, it has become ever more sophisticated and effective. Rothbard explains the origin of paper money, first as what were essentially warehouse receipts for real money (precious metal coins or bullion stored by its issuer and payable on demand), then increasingly abstract assets “backed” by only a fraction of the total value in circulation, and finally, with the advent of central banking, a fiction totally under the control of those who print the paper and their political masters. The whole grand racket of fractional reserve banking and the government inflationary engine it enables is explained in detail.

In the 1985 expanded edition, Rothbard adds a final twenty page chapter chronicling “The Monetary Breakdown of the West”, a tragedy in nine acts beginning with the classical gold standard of 1815–1914 and ending with the total severing of world currencies from any anchor to gold in March, 1973, ushering in the monetary chaos of endlessly fluctuating exchange rates, predatory currency manipulation, and a towering (and tottering) pyramid of completely unproductive financial speculation. He then explores the monetary utopia envisioned by the economic slavers: a world paper currency managed by a World Central Bank. There would no longer be any constraint upon the ability of those in power to pick the pockets of their subjects by depreciating the unit of account of the only financial assets they were permitted to own. Of course, this would lead to a slow-motion catastrophe, destroying enterprise, innovation, and investment, pauperising the population, and leading inevitably to civil unrest and demagogic political movements. Rothbard saw all of this coming, and those of us who understood his message knew exactly what was going to happen when they rolled out the Euro and a European Central Bank in 1991, which is just a regional version of the same Big Con.

This book remains, if I dare say, the gold standard when it comes to a short, lucid, and timeless explanation of monetary theory, history, the folly of governments, and its sad consequences. Is there any hope of restoring sanity in this age of universal funny money? Perhaps—the same technology which permits the establishment of cryptocurrencies such as Bitcoin radically reduces the transaction costs of using any number of competing currencies in a free market. While Gresham's Law holds that in a coercive un-free market bad money will drive out good, in a totally free market, where participants are able to use any store of value, unit of account, and medium of exchange they wish (free of government coercion through legal tender laws or taxation of currency exchanges), the best money will drive out its inferior competitors, and the quality of a given money will be evaluated based upon the transparency of its issuer and its performance for those who use it.

This book may be purchased from Amazon in either a print or Kindle edition, and is also available for free from the publisher, the Ludwig von Mises Institute, in HTML, PDF, and EPUB formats or as an audio book. The PDF edition is available in the English, Spanish, Danish, and Hungarian languages. The book is published under the Creative Commons Attribution License 3.0 and may be redistributed pursuant to the terms of that license.

Posted at 22:44

## Monday, July 15, 2019

### Reading List: The Man in the High Castle

Dick, Philip K. The Man in the High Castle. New York: Mariner Books, [1962] 2011. ISBN 978-0-547-57248-2.
The year is 1962. Following the victory of Nazi Germany and Imperial Japan in World War II, North America is divided into spheres of influence by the victors, with the west coast Pacific States of America controlled by Japan, the territory east of the Mississippi split north and south between what is still called the United States of America and the South, where slavery has been re-instituted, both puppet states of Germany. In between are the Rocky Mountain states, a buffer zone between the Japanese and German sectors with somewhat more freedom from domination by them.

The point of departure where this alternative history diverges from our timeline is in 1934, when Franklin D. Roosevelt is assassinated in Miami, Florida. (In our history, Roosevelt was uninjured in an assassination attempt in Miami in 1933 that killed the mayor of Chicago, Anton Cermak.) Roosevelt's vice president, John Nance Garner, succeeds to the presidency and is re-elected in 1936. In 1940, the Republican party retakes the White House, with John W. Bricker elected president. Garner and Bricker pursue a policy of strict neutrality and isolation, which allows Germany, Japan, and Italy to divide up the most of the world and coerce other nations into becoming satellites or client states. Then, Japan and Germany mount simultaneous invasions of the east and west coasts of the U.S., resulting in a surrender in 1947 and the present division of the continent.

By 1962, the victors are secure in their domination of the territories they have subdued. Germany has raced ahead economically and in technology, draining the Mediterranean to create new farmland, landing on the Moon and Mars, and establishing high-speed suborbital rocket transportation service throughout their far-flung territories. There is no serious resistance to the occupation in the former United States: its residents seem to be more or less resigned to second-class status under their German or Japanese overlords.

In the Pacific States the Japanese occupiers have settled in to a comfortable superiority over the vanquished, and many have become collectors of artefacts of the vanished authentic America. Robert Childan runs a shop in San Francisco catering to this clientèle, and is contacted by an official of the Japanese Trade Mission, seeking a gift to impress a visiting Swedish industrialist. This leads into a maze of complexity and nothing being as it seems as only Philip K. Dick (PKD) can craft. Is the Swede really a Swede or a German, and is he a Nazi agent or something else? Who is the mysterious Japanese visitor he has come to San Francisco to meet? Is Childan a supplier of rare artefacts or a swindler exploiting gullible Japanese rubes with fakes?

Many characters in the book are reading a novel called The Grasshopper Lies Heavy, banned in areas under German occupation but available in the Pacific States and other territories, which is an alternative history tale written by an elusive author named Hawthorne Abendsen, about a world in which the Allies defeated Germany and Japan in World War II and ushered in a golden age of peace, prosperity, and freedom. Abendsen is said to have retreated to a survivalist compound called the High Castle in the Rocky Mountain states. Characters we meet become obsessed with tracking down and meeting Abendsen. Who are they, and what are their motives? Keep reminding yourself, this is a PKD novel! We're already dealing with a fictional mysterious author of an alternative history of World War II within an alternative history novel of World War II by an author who is himself a grand illusionist.

It seems like everybody in the Pacific States, regardless of ethnicity or nationality, is obsessed with the I Ching. They are constantly consulting “the oracle” and basing their decisions upon it. Not just the westerners but even the Japanese are a little embarrassed by this, as the latter are aware that is it an invention of the Chinese, who they view as inferior, yet they rely upon it none the less. Again, the PKD shimmering reality distortion field comes into play as the author says that he consulted the I Ching to make decisions while plotting the novel, as does Hawthorne Abendsen in writing the novel within the novel.

This is quintessential PKD: the story is not so much about what happens (indeed, there is little resolution of any of the obvious conflicts in the circumstances of the plot) but rather instilling in the reader a sense that nothing is what it appears to be and, at the meta (or meta meta) level, that our history and destiny are ruled as much by chance (exemplified here by the I Ching) as by our intentions, will, and actions. At the end of the story, little or nothing has been resolved, and we are left only with questions and uncertainty. (PKD said that he intended a sequel, but despite efforts in that direction, never completed one.)

I understand that some kind of television adaptation loosely based upon the novel has been produced by one of those streaming services which are only available to people who live in continental-scale, railroad-era, legacy empires. I have not seen it, and have no interest in doing so. PKD is notoriously difficult to adapt to visual media, and today's Hollywood is, shall we say, not strong on nuance and ambiguity, which is what his fiction is all about.

Nuance and ambiguity…. Here's the funny thing. When I finished this novel, I was unimpressed and disappointed. I expected it to be great: I have enjoyed the fiction of PKD since I started to read his stories in the 1960s, and this novel won the Hugo Award for Best Novel in 1963, then the highest honour in science fiction. But the story struck me as only an exploration of a tiny corner of this rich alternative history. Little of what happens affects events in the large and, if it did, only long after the story ends. It was only while writing this that I appreciated that this may have been precisely what PKD was trying to achieve: that this is all about the contingency of history—that random chance matters much more than what we, or “great figures” do, and that the best we can hope for is to try to do what we believe is right when presented with the circumstances and events that confront us as we live our lives. I have no idea if you'll like this. I thought I would, and then I didn't, and now I, in retrospect, I do. Welcome to the fiction of Philip K. Dick.

Posted at 12:16

## Friday, July 12, 2019

Thor, Brad. Backlash. New York: Atria Books, 2019. ISBN 978-1-9821-0403-0.
This is the nineteenth novel in the author's Scot Harvath series, which began with The Lions of Lucerne (October 2010). This is a very different kind of story from the last several Harvath outings, which involved high-stakes international brinkmanship, uncertain loyalties, and threats of mass terror attacks. This time it's up close and personal. Harvath, paying what may be his last visit to Reed Carlton, his dying ex-CIA mentor and employer, is the object of a violent kidnapping attack which kills those to whom he is closest and spirits him off, drugged and severely beaten, to Russia, where he is to be subjected to the hospitality of the rulers whose nemesis he has been for many years (and books) until he spills the deepest secrets of the U.S. intelligence community.

After being spirited out of the U.S., the Russian cargo plane transporting him to the rendition resort where he is to be “de-briefed” crashes, leaving him…somewhere. About all he knows is that it's cold, that nobody knows where he is or that he is alive, and that he has no way to contact anybody, anywhere who might help.

This is a spare, stark tale of survival. Starting only with what he can salvage from the wreck of the plane and the bodies of its crew (some of whom he had to assist in becoming casualties), he must overcome the elements, predators (quadripedal and bipedal), terrain, and uncertainty about his whereabouts and the knowledge and intentions of his adversaries, to survive and escape.

Based upon what has been done to him, it is also a tale of revenge. To Harvath, revenge was not a low state: it was a necessity,

In his world, you didn't let wrongs go unanswered—not wrongs like this, and especially when you had the ability to do something. Vengeance was a necessary function of a civilized world, particularly at its margins, in its most remote and wild regions. Evildoers, unwilling to submit to the rule of law, needed to lie awake in their beds at night worried about when justice would eventually come for them. If laws and standards were not worth enforcing, then they certainly couldn't be worth following.

Harvath forms tenuous alliances with those he encounters, and then must confront an all-out assault by élite mercenaries who, apparently unsatisfied with the fear induced by fanatic Russian operatives, model themselves on the Nazi SS.

Then, after survival, it's time for revenge. Harvath has done his biochemistry homework and learned well the off-label applications of suxamethonium chloride. Sux to be you, Boris.

This is a tightly-crafted thriller which is, in my opinion, one of best of Brad Thor's novels. There is no political message or agenda nor any of the Washington intrigue which has occupied recent books. Here it is a pure struggle between a resourceful individual, on his own against amoral forces of pure evil, in an environment as deadly as his human adversaries.

Posted at 11:21

## Tuesday, July 9, 2019

Egan, Greg. Schild's Ladder. New York: Night Shade Books, [2002, 2004, 2013] 2015. ISBN 978-1-59780-544-5.
Greg Egan is one of the most eminent contemporary authors in the genre of “hard” science fiction. By “hard”, one means not that it is necessarily difficult to read, but that the author has taken care to either follow the laws of known science or, if the story involves alternative laws (for example, a faster than light drive, anti-gravity, or time travel) to define those laws and then remain completely consistent with them. This needn't involve tedious lectures—masters of science fiction, like Greg Egan, “show, don't tell”—but the reader should be able to figure out the rules and the characters be constrained by them as the story unfolds. Egan is also a skilled practitioner of “world building” which takes hard science fiction to the next level by constructing entire worlds or universes in which an alternative set of conditions are worked out in a logical and consistent way.

Whenever a new large particle collider is proposed, fear-mongers prattle on about the risk of its unleashing some new physical phenomenon which might destroy the Earth or, for those who think big, the universe by, for example, causing it to collapse into a black hole or causing the quantum vacuum to tunnel to a lower energy state where the laws of physics are incompatible with the existence of condensed matter and life. This is, of course, completely absurd. We have observed cosmic rays, for example the Oh-My-God particle detected by an instrument in Utah in 1991, with energies more than twenty million times greater than those produced by the Large Hadron Collider, the most powerful particle accelerator in existence today. These natural cosmic rays strike the Earth, the Moon, the Sun, and everything else in the universe all the time and have been doing so for billions of years and, if you look around, you'll see that the universe is still here. If a high energy particle was going to destroy it, it would have been gone long ago.

No, if somebody's going to destroy the universe, I'd worry about some quiet lab in the physics building where somebody is exploring very low temperatures, trying to beat the record which stands at, depending upon how you define it, between 0.006 degrees Kelvin (for a large block of metal) and 100 picokelvin (for nuclear spins). These temperatures, and the physical conditions they may create, are deeply unnatural and, unless there are similar laboratories and apparatus created by alien scientists on other worlds, colder than have ever existed anywhere in our universe ever since the Big Bang.

The cosmic microwave background radiation pervades the universe, and has an energy at the present epoch which corresponds to a temperature of about 2.73 degrees Kelvin. Every natural object in the universe is bathed in this radiation so, even in the absence of other energy sources such as starlight, anything colder than that will heated by the background radiation until it reaches that temperature and comes into equilibrium. (There are a few natural processes in the universe which can temporarily create lower temperatures, but nothing below 1° K has ever been observed.) The temperature of the universe has been falling ever since the Big Bang, so no lower temperature has ever existed in the past. The only way to create a lower temperature is to expend energy in what amounts to a super-refrigerator that heats up something else in return for artificially cooling its contents. In doing so, it creates a region like none other in the known natural universe.

Whenever you explore some physical circumstance which is completely new, you never know what you're going to find, and researchers have been surprised many times in the past. Prior to 1911, nobody imagined that it was possible for an electrical current to flow with no resistance at all, and yet in early experiments with liquid helium, the phenomenon of superconductivity was discovered. In 1937, it was discovered that liquid helium could flow with zero viscosity: superfluidity. What might be discovered at temperatures a tiny fraction of those where these phenomena became manifest? Answering that question is why researchers strive to approach ever closer to the (unattainable) absolute zero. Might one of those phenomena destroy the universe? Could be: you'll never know until you try.

This is the premise of this book, which is hard science fiction but also difficult. For twenty thousand years the field of fundamental physics has found nothing new beyond the unification of quantum mechanics and general relativity called “Sarumpaet's rules” or Quantum Graph Theory (QGT). The theory explained the fabric of space and time and all of the particles and forces within it as coarse-grained manifestations of transformations of a graph at the Planck scale. Researchers at Mimosa Station, 370 light years from Earth, have built an experimental apparatus, the Quietener, to explore conditions which have never existed before in the universe and test Sarumpaet's Rules at the limits. Perhaps the currently-observed laws of physics were simply a random choice made by the universe an unimaginably short time after the Big Bang and frozen into place by decoherence due to interactions with the environment, analogous to the quantum Zeno effect. The Quietener attempts to null out every possible external influence, even gravitational waves by carefully positioned local cancelling sources, in the hope of reproducing the conditions in which the early universe made its random choice and to create, for a fleeting instant, just trillionths of a second, a region of space with entirely different laws of physics. Sarumpaet's Rules guaranteed that this so-called novo-vacuum would quickly collapse, as it would have a higher energy and decay into the vacuum we inhabit.

Oops.

Six hundred and five years after the unfortunate event at Mimosa, the Mimosa novo-vacuum, not just stable but expanding at half the speed of light, has swallowed more than two thousand inhabited star systems, and is inexorably expanding through the galaxy, transforming everything in its path to—nobody knows. The boundary emits only an unstructured “borderlight” which provides no clue as to what lies within. Because the interstellar society has long ago developed the ability to create backups of individuals, run them as computer emulations, transmit them at light speed from star to star, and re-instantiate them in new bodies for fuddy-duddies demanding corporeal existence, loss of life has been minimal, but one understands how an inexorably growing sphere devouring everything in its path might be disturbing. The Rindler is a research ship racing just ahead of the advancing novo-vacuum front, providing close-up access to it for investigators trying to figure out what it conceals.

Humans (who, with their divergently-evolved descendants, biological and digitally emulated, are the only intelligent species discovered so far in the galaxy) have divided, as they remain wont to do, into two factions: Preservationists, who view the novo-vacuum as an existential threat to the universe and seek ways to stop its expansion and, ideally, recover the space it has occupied; and Yielders, who believe the novo-vacuum to be a phenomenon so unique and potentially important that destroying it before understanding its nature and what is on the other side of the horizon would be unthinkable. Also, being (post-)human, the factions are willing to resort to violence to have their way.

This leads to an adventure spanning time and space, and eventually a mission into a region where the universe is making it up as it goes along. This is one of the most breathtakingly ambitious attempts at world (indeed, universe) building ever attempted in science fiction. But for this reader, it didn't work. First of all, when all of the principal characters have backups stored in safe locations and can reset, like a character in a video game with an infinite number of lives cheat, whenever anything bad happens, it's difficult to create dramatic tension. Humans have transcended biological substrates, yet those still choosing them remain fascinated with curious things about bumping their adaptive uglies. When we finally go and explore the unknown, it's mediated through several levels of sensors, translation, interpretation, and abstraction, so what is described comes across as something like a hundred pages of the acid trip scene at the end of 2001.

In the distance, glistening partitions, reminiscent of the algal membranes that formed the cages in some aquatic zoos, swayed back and forth gently, as if in time to mysterious currents. Behind each barrier the sea changed color abruptly, the green giving way to other bright hues, like a fastidiously segregated display of bioluminescent plankton.

Oh, wow.

And then, it stops. I don't mean ends, as that would imply that everything that's been thrown up in the air is somehow resolved. There is an attempt to close the circle with the start of the story, but a whole universe of questions are left unanswered. The human perspective is inadequate to describe a place where Planck length objects interact in Planck time intervals and the laws of physics are made up on the fly. Ultimately, the story failed for me since it never engaged me with the characters—I didn't care what happened to them. I'm a fan of hard science fiction, but this was just too adamantine to be interesting.

The title, Schild's Ladder, is taken from a method in differential geometry which is used to approximate the parallel transport of a vector along a curve.

Posted at 13:54

## Sunday, July 7, 2019

### Reading List Management Software Updated

The Fourmilab reading list document tree is generated automatically from source documents kept as flat text files in a format similar to that of a Movable Type blog export file. These files are read by a Perl program called rlmake.pl which generates HTML files for the Web tree and compiles the various indices through which the list may be accessed (most recent, by year, month, topic, author, and title). The reading list management software is available for downloading and may be used in any manner you wish, but is utterly unsupported—you're entirely on your own. The Perl code will probably run with no problems on any system with a recent version of Perl (no external modules are required), but you will have to customise it to adapt to the document structure of your Web site and include your own personal data.

I have just posted an updated version of this software which adds two minor navigation features. When a reading list grows to substantial size (my list, begun in January 2001, now numbers 1173 books), scrolling through the lengthy author (975 authors) and title indices to find what you're looking for can be tedious. The update adds a JavaScript-implemented “hot key” navigation feature when displaying these indices. Simply move the mouse to the index window (it's in the side bar for authors and the main browser window for titles), click if necessary to set focus, and then type the first letter of the author or title you seek. The list will be scrolled so that entries which begin with that letter appear at the top of the window. You can then scroll down through the entries that start with the letter you typed. This probably won't work on a touch-screen mobile device unless you can figure out how to display the on-screen keyboard.

I've also cleaned up the Perl program a bit, but it's still plenty ugly.

Posted at 12:36

Murray, Charles and Catherine Bly Cox. Apollo. Burkittsville, MD: South Mountain Books, [1989, 2004] 2010. ISBN 978-0-9760008-0-8.
On November 5, 1958, NASA, only four months old at the time, created the Space Task Group (STG) to manage its manned spaceflight programs. Although there had been earlier military studies of manned space concepts and many saw eventual manned orbital flights growing out of the rocket plane projects conducted by NASA's predecessor, the National Advisory Committee for Aeronautics (NACA) and the U.S. Air Force, at the time of the STG's formation the U.S. had no formal manned space program. The initial group numbered 45 in all, including eight secretaries and “computers”—operators of electromechanical desk calculators, staffed largely with people from the NACA's Langley Research Center and initially headquartered there. There were no firm plans for manned spaceflight, no budget approved to pay for it, no spacecraft, no boosters, no launch facilities, no mission control centre, no astronauts, no plans to select and train them, and no experience either with human flight above the Earth's atmosphere or with more than a few seconds of weightlessness. And yet this team, the core of an effort which would grow to include around 400,000 people at NASA and its 20,000 industry and academic contractors, would, just ten years and nine months later, on July 20th, 1969, land two people on the surface of the Moon and then return them safely to the Earth.

Ten years is not a long time when it comes to accomplishing a complicated technological project. Development of the Boeing 787, a mid-sized commercial airliner which flew no further, faster, or higher than its predecessors, and was designed and built using computer-aided design and manufacturing technologies, took eight years from project launch to entry into service, and the F-35 fighter plane only entered service and then only in small numbers of one model a full twenty-three years after the start of its development.

In November, 1958, nobody in the Space Task Group was thinking about landing on the Moon. Certainly, trips to the Moon had been discussed in fables from antiquity to Jules Verne's classic De la terre à la lune of 1865, and in 1938 members of the British Interplanetary Society published a (totally impractical) design for a Moon rocket powered by more than two thousand solid rocket motors bundled together, which would be discarded once burned out, but only a year since the launch of the first Earth satellite and when nothing had been successfully returned from Earth orbit to the Earth, talk of manned Moon ships sounded like—lunacy.

The small band of stalwarts at the STG undertook the already daunting challenge of manned space flight with an incremental program they called Project Mercury, whose goal was to launch a single man into Earth orbit in a capsule (unable to change its orbit once released from the booster rocket, it barely deserved the term “spacecraft”) atop a converted Atlas intercontinental ballistic missile. In essence, the idea was to remove the warhead, replace it with a tiny cone-shaped can with a man in it, and shoot him into orbit. At the time the project began, the reliability of the Atlas rocket was around 75%, so NASA could expect around one in four launches to fail, with the Atlas known for spectacular explosions on the ground or on the way to space. When, in early 1960, the newly-chosen Mercury astronauts watched a test launch of the rocket they were to ride, it exploded less than a minute after launch. This was the fifth consecutive failure of an Atlas booster (although not all were so spectacular).

Doing things which were inherently risky on tight schedules with a shoestring budget (compared to military projects) and achieving an acceptable degree of safety by fanatic attention to detail and mountains of paperwork (NASA engineers quipped that no spacecraft could fly until the mass of paper documenting its construction and test equalled that of the flight hardware) became an integral part of the NASA culture. NASA was proceeding on its deliberate, step-by-step development of Project Mercury, and in 1961 was preparing for the first space flight by a U.S. astronaut, not into orbit on an Atlas, just a 15 minute suborbital hop on a version of the reliable Redstone rocket that launched the first U.S. satellite in 1958 when, on April 12, 1961, they were to be sorely disappointed when the Soviet Union launched Yuri Gagarin into orbit on Vostok 1. Not only was the first man in space a Soviet, they had accomplished an orbital mission, which NASA hadn't planned to attempt until at least the following year.

On May 5, 1961, NASA got back into the game, or at least the minor league, when Alan Shepard was launched on Mercury-Redstone 3. Sure, it was just a 15 minute up and down, but at least an American had been in space, if only briefly, and it was enough to persuade a recently-elected, young U.S. president smarting from being scooped by the Soviets to “take longer strides”. On May 25, less than three weeks after Shepard's flight, before a joint session of Congress, President Kennedy said, “I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the Moon and returning him safely to Earth.” Kennedy had asked his vice president, Lyndon Johnson, what goal the U.S. could realistically hope to achieve before the Soviets, and after consulting with the NASA administrator, James Webb, a Texas oil man and lawyer, and no other NASA technical people other than Wernher von Braun, he reported that a manned Moon landing was the only milestone the Soviets, with their heavy boosters and lead in manned space flight, were unlikely to do first. So, to the Moon it was.

The Space Task Group people who were, ultimately going to be charged with accomplishing this goal and had no advance warning until they heard Kennedy's speech or got urgent telephone calls from colleagues who had also heard the broadcast were, in the words of their leader, Robert Gilruth, who had no more warning than his staff, “aghast”. He and his team had, like von Braun in the 1950s, envisioned a deliberate, step-by-step development of space flight capability: manned orbital flight, then a more capable spacecraft with a larger crew able to maneuver in space, a space station to explore the biomedical issues of long-term space flight and serve as a base to assemble craft bound farther into space, perhaps a reusable shuttle craft to ferry crew and cargo to space without (wastefully and at great cost) throwing away rockets designed as long-range military artillery on every mission,followed by careful reconnaissance of the Moon by both unmanned and manned craft to map its surface, find safe landing zones, and then demonstrate the technologies that would be required to get people there and back safely.

All that was now clearly out the window. If Congress came through with the massive funds it would require, going to the Moon would be a crash project like the Manhattan Project to build the atomic bomb in World War II, or the massive industrial mobilisation to build Liberty Ships or the B-17 and B-29 bombers. The clock was ticking: when Kennedy spoke, there were just 3142 days until December 31, 1969 (yes, I know the decade actually ends at the end of 1970, since there was no year 0 in the Gregorian calendar, but explaining this to clueless Americans is a lost cause), around eight years and seven months. What needed to be done? Everything. How much time was there to do it? Not remotely enough. Well, at least the economy was booming, politicians seemed willing to pay the huge bills for what needed to be done, and there were plenty of twenty-something newly-minted engineering graduates ready and willing to work around the clock without a break to make real what they'd dreamed of since reading science fiction in their youth.

The Apollo Project was simultaneously one of the most epochal and inspiring accomplishments of the human species, far more likely to be remembered a thousand years hence than anything else that happened in the twentieth century, and at the same time a politically-motivated blunder which retarded human expansion into the space frontier. Kennedy's speech was at the end of May 1961. Perhaps because the Space Task Group was so small, it and NASA were able to react with a speed which is stunning to those accustomed to twenty year development projects for hardware far less complicated than Apollo.

In June and July [1961], detailed specifications for the spacecraft hardware were completed. By the end of July, the Requests for Proposals were on the street.

In August, the first hardware contract was awarded to M.I.T.'s Instrumentation Laboratory for the Apollo guidance system. NASA selected Merritt Island, Florida, as the site for a new spaceport and acquired 125 square miles of land.

In September, NASA selected Michoud, Louisiana, as the production facility for the Saturn rockets, acquired a site for the Manned Spacecraft Center—the Space Task Group grown up—south of Houston, and awarded the contract for the second stage of the Saturn [V] to North American Aviation.

In October, NASA acquired 34 square miles for a Saturn test facility in Mississippi.

In November, the Saturn C-1 was successfully launched with a cluster of eight engines, developing 1.3 million pounds of thrust. The contract for the command and service module was awarded to North American Aviation.

In December, the contract for the first stage of the Saturn [V] was awarded to Boeing and the contract for the third stage was awarded to Douglas Aircraft.

By January of 1962, construction had begun at all of the acquired sites and development was under way at all of the contractors.

Such was the urgency with which NASA was responding to Kennedy's challenge and deadline that all of these decisions and work were done before deciding on how to get to the Moon—the so-called “mission mode”. There were three candidates: direct-ascent, Earth orbit rendezvous (EOR), and lunar orbit rendezvous (LOR). Direct ascent was the simplest, and much like idea of a Moon ship in golden age science fiction. One launch from Earth would send a ship to the Moon which would land there, then take off and return directly to Earth. There would be no need for rendezvous and docking in space (which had never been attempted, and nobody was sure was even possible), and no need for multiple launches per mission, which was seen as an advantage at a time when rockets were only marginally reliable and notorious for long delays from their scheduled launch time. The downside of direct-ascent was that it would require an enormous rocket: planners envisioned a monster called Nova which would have dwarfed the Saturn V eventually used for Apollo and required new manufacturing, test, and launch facilities to accommodate its size. Also, it is impossible to design a ship which is optimised both for landing under rocket power on the Moon and re-entering Earth's atmosphere at high speed. Still, direct-ascent seemed to involve the least number of technological unknowns. Ever wonder why the Apollo service module had that enormous Service Propulsion System engine? When it was specified, the mission mode had not been chosen, and it was made powerful enough to lift the entire command and service module off the lunar surface and return them to the Earth after a landing in direct-ascent mode.

Earth orbit rendezvous was similar to what Wernher von Braun envisioned in his 1950s popular writings about the conquest of space. Multiple launches would be used to assemble a Moon ship in low Earth orbit, and then, when it was complete, it would fly to the Moon, land, and then return to Earth. Such a plan would not necessarily even require a booster as large as the Saturn V. One might, for example, launch the lunar landing and return vehicle on one Saturn I, the stage which would propel it to the Moon on a second, and finally the crew on a third, who would board the ship only after it was assembled and ready to go. This was attractive in not requiring the development of a giant rocket, but required on-time launches of multiple rockets in quick succession, orbital rendezvous and docking (and in some schemes, refuelling), and still had the problem of designing a craft suitable both for landing on the Moon and returning to Earth.

Lunar orbit rendezvous was originally considered a distant third in the running. A single large rocket (but smaller than Nova) would launch two craft toward the Moon. One ship would be optimised for flight through the Earth's atmosphere and return to Earth, while the other would be designed solely for landing on the Moon. The Moon lander, operating only in vacuum and the Moon's weak gravity, need not be streamlined or structurally strong, and could be potentially much lighter than a ship able to both land on the Moon and return to Earth. Finally, once its mission was complete and the landing crew safely back in the Earth return ship, it could be discarded, meaning that all of the hardware needed solely for landing on the Moon need not be taken back to the Earth. This option was attractive, requiring only a single launch and no gargantuan rocket, and allowed optimising the lander for its mission (for example, providing better visibility to its pilots of the landing site), but it not only required rendezvous and docking, but doing it in lunar orbit which, if they failed, would strand the lander crew in orbit around the Moon with no hope of rescue.

After a high-stakes technical struggle, in the latter part of 1962, NASA selected lunar orbit rendezvous as the mission mode, with each landing mission to be launched on a single Saturn V booster, making the decision final with the selection of Grumman as contractor for the Lunar Module in November of that year. Had another mission mode been chosen, it is improbable in the extreme that the landing would have been accomplished in the 1960s.

The Apollo architecture was now in place. All that remained was building machines which had never been imagined before, learning to do things (on-time launches, rendezvous and docking in space, leaving spacecraft and working in the vacuum, precise navigation over distances no human had ever travelled before, and assessing all of the “unknown unknowns” [radiation risks, effects of long-term weightlessness, properties of the lunar surface, ability to land on lunar terrain, possible chemical or biological threats on the Moon, etc.]) and developing plans to cope with them.

This masterful book is the story of how what is possibly the largest collection of geeks and nerds ever assembled and directed at a single goal, funded with the abundant revenue from an economic boom, spurred by a geopolitical competition against the sworn enemy of liberty, took on these daunting challenges and, one by one, overcame them, found a way around, or simply accepted the risk because it was worth it. They learned how to tame giant rocket engines that randomly blew up by setting off bombs inside them. They abandoned the careful step-by-step development of complex rockets in favour of “all-up testing” (stack all of the untested pieces the first time, push the button, and see what happens) because “there wasn't enough time to do it any other way”. People were working 16–18–20 hours a day, seven days a week. Flight surgeons in Mission Control handed out “go and whoa pills”—amphetamines and barbiturates—to keep the kids on the console awake at work and asleep those few hours they were at home—hey, it was the Sixties!

This is not a tale of heroic astronauts and their exploits. The astronauts, as they have been the first to say, were literally at the “tip of the spear” and would not have been able to complete their missions without the work of almost half a million uncelebrated people who made them possible, not to mention the hundred million or so U.S. taxpayers who footed the bill.

This was not a straight march to victory. Three astronauts died in a launch pad fire the investigation of which revealed shockingly slapdash quality control in the assembly of their spacecraft and NASA's ignoring the lethal risk of fire in a pure oxygen atmosphere at sea level pressure. The second flight of the Saturn V was a near calamity due to multiple problems, some entirely avoidable (and yet the decision was made to man the next flight of the booster and send the crew to the Moon). Neil Armstrong narrowly escaped death in May 1968 when the Lunar Landing Research Vehicle he was flying ran out of fuel and crashed. And the division of responsibility between the crew in the spacecraft and mission controllers on the ground had to be worked out before it would be tested in flight where getting things right could mean the difference between life and death.

What can we learn from Apollo, fifty years on? Other than standing in awe at what was accomplished given the technology and state of the art of the time, and on a breathtakingly short schedule, little or nothing that is relevant to the development of space in the present and future. Apollo was the product of a set of circumstances which happened to come together at one point in history and are unlikely to ever recur. Although some of those who worked on making it a reality were dreamers and visionaries who saw it as the first step into expanding the human presence beyond the home planet, to those who voted to pay the forbidding bills (at its peak, NASA's budget, mostly devoted to Apollo, was more than 4% of all Federal spending; in recent years, it has settled at around one half of one percent: a national commitment to space eight times smaller as a fraction of total spending) Apollo was seen as a key battle in the Cold War. Allowing the Soviet Union to continue to achieve milestones in space while the U.S. played catch-up or forfeited the game would reinforce the Soviet message to the developing world that their economic and political system was the wave of the future, leaving decadent capitalism in the dust.

A young, ambitious, forward-looking president, smarting from being scooped once again by Yuri Gagarin's orbital flight and the humiliation of the débâcle at the Bay of Pigs in Cuba, seized on a bold stroke that would show the world the superiority of the U.S. by deploying its economic, industrial, and research resources toward a highly visible goal. And, after being assassinated two and a half years later, his successor, a space enthusiast who had directed a substantial part of NASA's spending to his home state and those of his political allies, presented the program as the legacy of the martyred president and vigorously defended it against those who tried to kill it or reduce its priority. The U.S. was in an economic boom which would last through most of the Apollo program until after the first Moon landing, and was the world's unchallenged economic powerhouse. And finally, the federal budget had not yet been devoured by uncontrollable “entitlement” spending and national debt was modest and manageable: if the national will was there, Apollo was affordable.

This confluence of circumstances was unique to its time and has not been repeated in the half century thereafter, nor is it likely to recur in the foreseeable future. Space enthusiasts who look at Apollo and what it accomplished in such a short time often err in assuming a similar program: government funded, on a massive scale with lavish budgets, focussed on a single goal, and based on special-purpose disposable hardware suited only for its specific mission, is the only way to open the space frontier. They are not only wrong in this assumption, but they are dreaming if they think there is the public support and political will to do anything like Apollo today. In fact, Apollo was not even particularly popular in the 1960s: only at one point in 1965 did public support for funding of human trips to the Moon poll higher than 50% and only around the time of the Apollo 11 landing did 50% of the U.S. population believe Apollo was worth what was being spent on it.

In fact, despite being motivated as a demonstration of the superiority of free people and free markets, Project Apollo was a quintessentially socialist space program. It was funded by money extracted by taxation, its priorities set by politicians, and its operations centrally planned and managed in a top-down fashion of which the Soviet functionaries at Gosplan could only dream. Its goals were set by politics, not economic benefits, science, or building a valuable infrastructure. This was not lost on the Soviets. Here is Soviet Minister of Defence Dmitriy Ustinov speaking at a Central Committee meeting in 1968, quoted by Boris Chertok in volume 4 of Rockets and People.

…the Americans have borrowed our basic method of operation—plan-based management and networked schedules. They have passed us in management and planning methods—they announce a launch preparation schedule in advance and strictly adhere to it. In essence, they have put into effect the principle of democratic centralism—free discussion followed by the strictest discipline during implementation.

This kind of socialist operation works fine in a wartime crash program driven by time pressure, where unlimited funds and manpower are available, and where there is plenty of capital which can be consumed or borrowed to pay for it. But it does not create sustainable enterprises. Once the goal is achieved, the war won (or lost), or it runs out of other people's money to spend, the whole thing grinds to a halt or stumbles along, continuing to consume resources while accomplishing little. This was the predictable trajectory of Apollo.

Apollo was one of the noblest achievements of the human species and we should celebrate it as a milestone in the human adventure, but trying to repeat it is pure poison to the human destiny in the solar system and beyond.

This book is a superb recounting of the Apollo experience, told mostly about the largely unknown people who confronted the daunting technical problems and, one by one, found solutions which, if not perfect, were good enough to land on the Moon in 1969. Later chapters describe key missions, again concentrating on the problem solving which went on behind the scenes to achieve their goals or, in the case of Apollo 13, get home alive. Looking back on something that happened fifty years ago, especially if you were born afterward, it may be difficult to appreciate just how daunting the idea of flying to the Moon was in May 1961. This book is the story of the people who faced that challenge, pulled it off, and are largely forgotten today.

Both the 1989 first edition and 2004 paperback revised edition are out of print and available only at absurd collectors' prices. The Kindle edition, which is based upon the 2004 edition with small revisions to adapt to digital reader devices is available at a reasonable price, as is an unabridged audio book, which is a reading of the 2004 edition. You'd think there would have been a paperback reprint of this valuable book in time for the fiftieth anniversary of the landing of Apollo 11 (and the thirtieth anniversary of its original publication), but there wasn't.

Project Apollo is such a huge, sprawling subject that no book can possibly cover every aspect of it. For those who wish to delve deeper, here is a reading list of excellent sources. I have read all of these books and recommend every one. For those I have reviewed, I link to my review; for others, I link to a source where you can obtain the book.

If you wish to commemorate the landing of Apollo 11 in a moving ceremony with friends, consider hosting an Evoloterra celebration.

Posted at 11:58

## Tuesday, July 2, 2019

Suarez, Daniel. Delta-v. New York: Dutton, 2019. ISBN 978-1-5247-4241-6.
James Tighe is an extreme cave diver, pushing the limits of human endurance and his equipment to go deeper, farther, and into unexplored regions of underwater caves around the world. While exploring the depths of a cavern in China, an earthquake triggers disastrous rockfalls in the cave, killing several members of his expedition. Tighe narrowly escapes with his life, leading the survivors to safety, and the video he recorded with his helmet camera has made him an instant celebrity. He is surprised and puzzled when invited by billionaire and serial entrepreneur Nathan Joyce to a party on Joyce's private island in the Caribbean. Joyce meets privately with Tighe and explains that his theory of economics predicts a catastrophic collapse of the global debt bubble in the near future, with the potential to destroy modern civilisation.

Joyce believes that the only way to avert this calamity is to jump start the human expansion into the solar system, thus creating an economic expansion into a much larger sphere of activity than one planet and allowing humans to “grow out” of the crushing debt their profligate governments have run up. In particular, he believes that asteroid mining is the key to opening the space frontier, as it will provide a source of raw materials which do not have to be lifted at prohibitive cost out of Earth's deep gravity well. Joyce intends to use part of his fortune to bootstrap such a venture, and invites Tighe to join a training program to select a team of individuals ready to face the challenges of long-term industrial operations in deep space.

Tighe is puzzled, “Why me?” Joyce explains that much more important than a background in aerospace or mining is the ability to make the right decisions under great pressure and uncertainty. Tighe's leadership in rescuing his dive companions demonstrated that ability and qualified him to try out for Joyce's team.

By the year 2033, the NewSpace companies founded in the early years of the 21st century have matured and, although taking different approaches, have come to dominate the market for space operations, mostly involving constellations of Earth satellites. The so-called “NewSpace Titans” (names have been changed, but you'll recognise them from their styles) have made their billions developing this industry, and some have expressed interest in asteroid mining, but mostly via robotic spacecraft and on a long-term time scale. Nathan Joyce wants to join their ranks and advance the schedule by sending humans to do the job. Besides, he argues, if the human destiny is to expand into space, why not get on with it, deploying their versatility and ability to improvise on this difficult challenge?

The whole thing sounds rather dodgy to Tighe, but cave diving does not pay well, and the signing bonus and promised progress payments if he meets various milestones in the training programme sound very attractive, so he signs on the dotted line. Further off-putting were a draconian non-disclosure agreement and an “Indemnity for Accidental Death and Dismemberment” which was sprung on candidates only after arriving at the remote island training facility. There were surveillance cameras and microphones everywhere, and Tighe and others speculated they may be part of an elaborate reality TV show staged by Joyce, not a genuine space project.

The other candidates were from all kinds of backgrounds: ex-military, former astronauts, BASE jumpers, mountaineers, scientists, and engineers. There were almost all on the older side for adventurers: mid-thirties to mid-forties—something about cosmic rays. And most of them had the hallmarks of DRD4-7R adventurers.

As the programme gets underway, the candidates discover it resembles Special Forces training more than astronaut candidate instruction, with a series of rigorous tests evaluating personal courage, endurance, psychological stability, problem-solving skills, tolerance for stress, and the ability to form and work as a team. Predictably, their numbers are winnowed as they approach the milestone where a few will be selected for orbital training and qualification for the deep space mission.

Tighe and the others discover that their employer is anything but straightforward, and they begin to twig to the fact that the kind of people who actually open the road to human settlement of the solar system may resemble the ruthless railroad barons of the 19th century more than the starry-eyed dreamers of science fiction. These revelations continue as the story unfolds.

After gut-wrenching twists and turns, Tighe finds himself part of a crew selected to fly to and refine resources from a near-Earth asteroid first reconnoitered by the Japanese Hayabusa2 mission in the 2010s. Risks are everywhere, and not just in space: corporate maneuvering back on Earth can kill the crew just as surely as radiation, vacuum, explosions, and collisions in space. Their only hope may be a desperate option recalling one of the greatest feats of seamanship in Earth's history.

This is a gripping yarn in which the author confronts his characters with one seemingly insurmountable obstacle and disheartening setback after another, then describes how these carefully selected and honed survivors deal with it. There are no magical technologies: all of the technical foundations exist today, at least at the scale of laboratory demonstrations, and could plausibly be scaled up to those in the story by the mid-2030s. The intricate plot is a salutary reminder that deception, greed, dodgy finances, corporate hijinks, bureaucracy, and destructively hypertrophied egos do not stop at the Kármán line. The conclusion is hopeful and a testament to the place for humans in the development of space.

A question and answer document about the details underlying the story is available on the author's Web site.

Posted at 14:17