Getting to know a hive mind

 kw: book reviews, science fiction, mysteries, murder mysteries, space fiction, space aliens, sentient starships, writers, generated images

In the opening scene of Infinite Archive by Mur Lafferty, the protagonist, Mallory Viridian, is learning to communicate with a hive mind that consists of a large number of wasplike aliens. As I read, I realized that I would really like to illustrate the book. My "contract artist" for the images in this post is GPT-Image-1.5, accessed via Leonardo AI.

The book is chock full of ideas: multiple kinds of hive minds; aliens ranging from the Gneiss (my favorite; they are living rocks) to the Sundry (one of a few species of waspoids) to the Miu (catlike), and of course, the spaceships themselves; living libraries—both the larger spaceships and the hive minds—; language interpretation via a brain app…and so forth. The setting for most of the action is a mystery writers' convention being held on an enormous spaceship that is quite different from the others nearby at a station cluster. Mallory is a mystery writer. She also has a "talent" for being if not present, then nearby when murders happen. She solves the mystery, then writes a book about it. It's a living. In this case, communion with a hive mind, and the powers that this unlocks, are crucial to catching the murderer.

In the 2040's or so, First Contact occurred a number of years in the past (apparently about 2030), there are lots of loosely confederated alien species, and humans aren't yet trusted enough to be given the secret of space flight. But humans can apparently afford space tourism and even get jobs aboard certain ships, so they get to gallivant around the galaxy with everyone else. In a charming turn, spaceships aren't built, they are grown. Mallory has been given custody of a baby spaceship about the size of a tennis ball. It seems to be able to lift out of her jacket pocket and zip off at times, without burning anything. The drive mechanism is not mentioned. Antigrav, perhaps? By the time things get serious the little ship, named Mobius is bigger, softball sized, and beginning to look more like a rugby ball. Later on he (ships have gender) figures in a rivalry between different wasplike aliens.

It is hard to get too deep into the plot of the story without giving too much away. So let's stick with some ideas and their ramifications. Two of Mallory's allies are seen in this image, along with a catlike alien rather different from a Miu, but this is the best that the program could offer. The Miu is no ally, not quite an enemy, but definitely a player, just in another conceptual direction.

I'll skip to the convention. It doesn't get off to much of a start before there is trouble. First, Mallory's book agent is present, and tries to get her involved in a LARP (Live-Action Role Play) "game" that doesn't go well. I'll leave it to the reader to learn why she storms out. Then, it appears that some of the other authors present who have the same agent aren't all happy with one another, nor with the agent.

The convention itself kicks off with several acts including a performance by a popular Punk-ish band, apparently all human, though this isn't explicitly stated. 

During the musical performance, the first murder occurs, soon followed by a second. Mallory goes into high gear. She is now comfortable communing with, and getting help from, the Sundry hive mind she's been bonding with. This helps a lot, and I'd better leave it there.

I understand that Ms Lafferty has written other books. I plan to track them down. This one is an enjoyable romp.

A third MEGAPACK

kw: book reviews, science fiction, collections, anthologies, short stories, space opera, space aliens

My original purchase from the MEGAPACK® series included three e-books. I already finished and reviewed two of them. This is the third. Like other early volumes in the series, it is titled The 13th Science Fiction Megapack. Later collections of classics have a theme or author as a focus. This volume contains 26 stories, eleven published in 1963, and the rest scattered from 1930 to 2010. All were new to me.

A goodly proportion of the stories experiment with taking the alien's eye view. Two of these, sitting back-to-back, are "The God-Plllnk" by Jerome Bixby and "A Guest of Ganymede" by C.C. MacApp, both published in 1963. In both stories, the invaders from Earth are either consumed or subsumed. Sobering.

Others take a recent discovery or trend then present and extend it. One of these, "Steak Tartare and the Cats of Gari Babakin Station", by Mary A. Turzillo, published in 2009, riffs on the effects of infection by Toxoplasma gondii, a parasite that afflicts cats and eventually nearly everyone who owns a cat. With just a little studied exaggeration, and imputing to Toxoplasma characteristics of a few other parasites, including the one that turns rats from cat-fearing to cat-seeking, we find an entertaining tale of psychology and motivation. The cats and their "guests" take over Mars.

From time to time writers tackle the possible interactions between archaic humans and Neanderthals, some 30,000 years ago or more. "The Day is Done" by Lester del Rey, published in 1939 is one of the earliest and best. (My second-favorite, "The Ugly Little Boy" by Isaac Asimov, is from 1958). del Rey's very moving story is set as the last of the Neanderthals are vanishing.

One of the stories of 1963, "The Girl in His Mind" by Robert F. Young, is based on a sort of dream "technology" that seems to foreshadow a dreamland called "the Commons" in stories by Matthew Hughes (see this review from 2006). In both 1963 and 2006, the writers take lucid dreaming a few quantum leaps beyond anything actual lucid dreamers (such as myself) experience. Lucid dreaming as we know it permits the dreamer to have some control over the story line and content of a dream. In my case, most frequently, I "stick a toe" into a dream that presents itself, and if I don't like where it may go, I open my eyes briefly and banish it. Once a dream starts up that I am more happy with, I let myself fall the rest of the way to sleep. Often, but not always, I know I am in a dream and I direct it more to my liking. Other times, I have "ordinary" dreams, that just happen with me as more of an observer than a participant. Any of this is a far cry from the long quests described by authors Young and Hughes.

I think I enjoy classic science fiction so much more than most "modern" writing because the authors aren't grinding an axe, at least not in the overt way that is nearly universal today, which is why I read so little modern science fiction. Writers of the world: present your views and your reasoning; do not attempt to impose them or shame your readers – I am shameless anyway, and I'll shame you right back!

Sing for your supper - er - survival

kw: book reviews, science fiction, space aliens, first contact, singing, competitions

Well, after a few serious books in a row, I was ready for some mindless escapism. Boy, did I find that! Space Opera, by Catherynne M. Valente is about the silliest bit of SF I've come across, yet based on an idea worth thinking about.

Scenario: When the aliens arrive, they arrive to everyone at once. By some kind of projection, a bizarre-looking alien being visits every single human on Earth, wherever they happen to be at the time, and converses with everyone individually (only much later in the book is there just a hint about translation technology). After various amounts of time for the human involved to get over the shock, the discussion gets serious (as serious as anything gets in this book): One human person or group is to be entered into a Galactic singing contest, to determine if humans are sentient. It turns out that "sentience" is not so self-evident as we'd like to think.

According to the Esca, the species chosen to "recruit" a human singing group, all entrants in the song festival are ranked, including any newcomers (in this case, humans). If a newcomer winds up ranked dead last, the species is indeed "Dead Last": the entire species is to be exterminated and the planetary biosphere will be given another few million years to evolve a new, purportedly sentient, species. Rinse, Dry, Repeat as necessary. The Esca were the most recent species to "enter" the contest, and are quite proud that they came in Eighth, rather than something like Seventy-Fourth, or whatever Dead Last would be. The proven sentient beings of the Galaxy have decided that the extinction of an occasional species is the price to be paid for the peace-promoting songfest. It succeeded "Galactic War X", after all.

To give you an idea of the hyper-enthusiasm of language Ms Valente, here is the description of the leading member of the Absolute Zeroes, the group that is taken a few thousand light-years to the competition venue, a certain Mr. Decibel Jones (né Danesh Jalo):

…a leggy psychedelic ambidextrous omnisexual gendersplat glitterpunk financially punch-drunk ethnically ambiguous glamrock messiah…

The prose reminds me of teachers of the art of composition, who advised us, "Use more adjectives!" This book is about 2/3 adjectives, frequently in sentences that run 100-200 words. Sentences full of immense enthusiasm. Also full of neologisms. Amazingly, newly coined words seem to fit into the text around them and practically define themselves. Other than the occasional jarring bit of potty-mouth, prose like that just washes over me like perfumed olive oil.

The concept is actually based on a real bit of history, though "last place" in a certain global competition does not result in anyone's being exterminated.

I don't know if I could call this escapism at its best, but it is certainly escapism of a most compelling sort.

First contact - with AI

kw: book reviews, science fiction, space travel, space aliens, artificial intelligence

Considering recent titles by Ben Bova, I figure that his new novel Survival is one of a series, probably the second or third. Very generally, humans have been contacted by a starfaring machine culture that they call the Predecessors, an altruistic one that is attempting to contact as many planet-bound cultures as they can, to help them prepare to survive a "Death Wave" that is spreading from the galactic core. Periodic cataclysms there emit enormous waves of gamma radiation that scour all the planets in a galaxy of organic life, and also any "machine life" that is insufficiently hardened against the radiation.

Much of the dramatic tension in the book, aside from a couple of love stories, concerns the contrast between the Predecessors and another machine culture on a planet about 2,000 light-years toward the galactic center from Earth, dubbed the Survivors. The Survivors are not altruistic. They are motivated only by a drive to survive that was built into them by the organic beings that first created them and then perished in an earlier death wave. A human ship sent to warn the Survivors is held captive by them. They do not wish to receive such help, having survived prior death waves, and they are supremely indifferent to the fate of the organic life on their planet, even though they had a hand in preserving remnants of earlier biospheres, and re-instating them.

It would give away too much to describe more of the plot. Of course, this would not be a Ben Bova novel if the humans didn't find a way to influence the Survivors.

I am interested in decision making, by men and machines. A number of psychological and sociological studies in the past couple of decades have demonstrated that an emotionless, Spock-like hyper-logical being would actually be crippled when it came to deciding between competing alternatives. People who have suffered injuries that disconnect their intellect from their emotions, or that destroy their emotional centers, are incapable of making decisions. It seems that we need the ability to like or even love one thing more than another. Emotion is not contrary to logic, but in some way amplifies it.

We were, or at least my generation was, taught that our brains evolved in layers, with an entirely reactive "reptile brain" or even "fish brain" overlain by an emotional "rat brain", all wrapped in a cerebral cortex, the "higher brain" in which free will, creativity and intelligence resides. Further, if we learned a smidgen of endocrinology, we find that emotion is a largely bodily function, mediated by hormones and other small molecules that motivate us, or its opposite, in response to many kinds of stimuli. The reality is not all that simple. Disconnect the cortex from the inner layers, and reasoning spins along without having any "hooks" to pick one alternative over another.

The "modern" (50-70 years) efforts to create Artificial Intelligence (AI) comprise two branches. The engineering branch includes various attempts to replicate human reason by finding all the rules we follow. The "poster child" for this branch is the Expert System, much touted 20-30 years ago. Its best-known example was the Caduceus System for medical diagnosis. It was supposed to be able to ask a doctor or patient a series of questions and then produce a differential diagnosis of any condition. It could eventually diagnose about 1,000 conditions, a small fraction of the total. As is typical of the field of AI in general, it had a few dramatic successes amidst a great number of equivocal results and a large mass of failures.

The heuristic branch of AI includes neural nets and machine learning systems. A neural net is a framework that is thought to (very roughly) represent natural networks of neurons, and while it can be implemented in hardware, it is most often emulated by software running on a multi-core processor. A machine learning system can be based on a neural net, or on other technologies that are being tried on a rather empirical basis, almost trial-and-error. The Watson system, which won a round of Jeopardy against two very talented men, is the current exemplar. I doesn't make the news much these days. It cost billions to develop, and a number of applications (besides winning game shows) are still being developed. It has been 7 years since the Jeopardy event. So far as I can find out, its main strength is parsing and answering questions posed in natural language, presumably orally, and it is mainly being used for decision support in the treatment of lung cancer.

Many of us now encounter AI in the form of Siri, Alexa, Cortana or a few other voice avatars of our smart phones and "thing in the den" systems. They can indeed parse our vocalizations into text, and then the "big computer in the cloud" can come up with an answer for us. A few years ago a short article in the endpapers of Scientific American touted a machine system that supposedly exceeded the human brain in processing speed and memory capacity. Just a bit of miniaturization is needed before such a "machine brain" can be installed in Robby the Robot, however: the system requires a 9 megawatt power plant to support the electronics and the cooling systems, and fills a warehouse. Can we expect technology to advance until such a system is lunch-pail size and runs of a lithium battery? Can Moore's Law (very roughly: capacity tends to double about every 2 years) deal with this?

Wouldn't you know it, Moore's Law ended about 15 years ago with the development of CPU cores (because more than one CPU is now put on a chip) that run in the 3-4 GHz range. That has been the limit. I built the PC I am using about 8 years ago, to be a middle-of-the-road desktop system. It is still a middle-of-the-road system. In the 1980's a machine with this level of compute power was called a supercomputer. Today's supercomputers are enormous arrays of 4 GHz multicore processors running special software so they can effectively communicate and thus break up a complex process into numerous subprocesses. Had Moore's Law continued from 2005 until today, a single-core processor running at a clock speed close to 1 THz would be the basis of most systems (and phones, etc.), and a large chip holding up to 1,024 cores would form the basis of supercomputers that would fit in a filing cabinet-size unit, consuming no more than a few hundred watts.

Will quantum computing re-start Moore's Law where it left off? So far, it is a great deal harder to take advantage of quantum coherence and decoherence than anybody predicted in the 1990's when "quantum computing" was coined. Without that, however, we have little hope of developing a "machine brain" to rival the mammalian brain for its combination of size and capacity.

And we still have no clue how to even define consciousness, let alone reproduce it. Every SciFi story about artificial consciousness either finesses it with "it just happened when we put together enough circuits", or doesn't try to describe its workings at all. Based on the studies mentioned earlier, a big component of consciousness is our emotional response system(s). We really don't understand that, and until we do, it may be impossible to develop a Watson-like "decision support system" into an effective "decision system".

Still, a well-told tale of how we might interact with any machine civilizations out there is a welcome diversion from the "organic" aliens we usually encounter. It gets the brain cells working in a new direction or two...a good thing.

A millennial in space

kw: book reviews, science fiction, near-future, space aliens

Caution: the book reviewed was written in the language of many millennials and late Gen-Xers, including the casual cussin' my generation calls "potty mouth." It's not suitable for youngsters you wish to shelter from such language.

I wonder why space aliens are so frequently imagined as having magical attributes. In Spaceman of Bohemia by Jaroslav Kalfař, a Czech astronaut on a solo flight of 8 months' duration, to a mysterious purple cloud between Earth and Venus, spends a lot of time with a spider-like being that apparently talks to him in his language, but soundlessly, in his mind. It also rifles through his memories.

The real thrust of the story is, what is real? what is imaginary? How does the ill-starred astronaut return to Earth after the destruction of his space capsule, from a distance of tens of millions of miles? I was reminded of The Life of Pi (reviewed in 2015), and the long trip the young man Pi takes in a lifeboat with a tiger as his companion. The same ambiguity fills both stories.

In its wider sense the story is one of someone cycling back to the beginning to restart with a wiser outlook. Yet the protagonist is full of obsessions, and not all have been resolved at the end. Was his experience more delusion than fact, and is he still delusional? Probably.

About half the chapters are flashbacks to the astronaut's formative experiences, from the Velvet Revolution to the "Capitalist Invasion" of Prague. Assuming the history is accurate, there are a few things one can learn about the development of Czechoslovakia into the new nations that succeeded it after 1989, and a few things to learn about peasant life pretty much anywhere in Eastern Europe in those years.

I wonder how much astronomy and cosmology the author has been exposed to. The purple cloud is supposedly emitted by a "comet … from the Canis Major galaxy." There actually is a dwarf galaxy well behind the Canis Major constellation. It is about 25,000 light-years away. All known comets are members of our solar system, and perhaps a very few originate as far away as half a light year. So this is a book for the astronomically illiterate.

The book jacket blurbs treat the book as a great feat of humor. I found nothing funny in it. I wonder what joke I have been left out of. I'll chalk that up to a generational thing, and remark only that, if this is humor, I tremble for the generation now entering middle age.

As usual, the aliens is us

kw: book reviews, science fiction, space aliens, speculative fiction, short stories, collections, essays

I note upon looking back through my records that I have previously read only two books by David Brin. I reckon it is time to remedy that. His recent book Insistence of Vision gathers stories and a couple of excerpts from throughout his writing career, together with brief story notes and two essays on the craft of fiction writing and his views on its value (positive, naturally, but the key is why it is valuable). The first essay is titled "The Heresy of Science Fiction" and the second, "Waging War With Reality".

One core idea from the first essay is worth abstracting: The message underlying much speculative fiction is one of two moods, either "give up and give in" or "try harder and push forward". Brin is of the latter persuasion, concluding, "…we are the rebels. We who think change might (possibly) bring good." The following 21 stories (including a novelette) and the closing essay illustrate his optimism.

Even in a rather dark story such as the title one, "Insistence of Vision", in which the punishment for certain crimes is blinding (apparently reversible) of the natural eyes, and forcible reliance on virtual reality jacked right into the brain, which is not operative in certain "free zones"; in such a story the actual message is that sanctions more humane than those now practiced might be possible, and even effective.

Here is a basic formula: Discern a trend in society, technology, fashion, or whatever, and extrapolate it to a logical conclusion…or an illogical one! It seems simple enough, and one might think it would lead to one-dimensional fiction. Most certainly it can. But the dimensions available are as numerous as human personal variation allows, and the possibilities are endless. That is just one tool of speculative fiction. Consider a visit by Martians or some similar aliens who out-Spock Mr. Spock. Emotionless, logical to a severe extreme, and they have a grievance against certain persons here on Earth (One thinks of a space probes crash-landing and injuring someone powerful. Kind of like Dorothy and her Kansas house, dropped on the Wicked Witch of the East). How might those beings take vengeance? "Mars Opposition" provides one possible scenario. The plot twist upon the narrator is a "Brin Special", the kind of eye-opening surprise he is noted for.

What makes David Brin special is the believableness of his space aliens. That rests in the glimmer of familiarity. No matter how alien, you find yourself thinking, "I know someone like that" or "that's what I'd do!".

Looking the stories over, I find I must either summarize them all or stop here. I'd better leave more room for a reader's delight. Get this book, and do restrain yourself, so that it lasts more than a single sitting!

The man behind the Vulcan

kw: book reviews, nonfiction, biographies, actors, acting, television series, space, space aliens

My family and I all loved Star Trek when it was first aired in 1966-69. By mid-1967, my mother would get dinner prepared in time for us to rush into the den and watch the show while eating on TV trays. It was her favorite TV series, as it was for most of us. Over the years of reruns, we re-viewed many of our favorite episodes. But none of us became an overt "trekkie", going to conventions or wearing costumes.

At times I have read articles about the cast and how they got along. The main thread was often how arrogant and generally unliked William Shatner was, and how beloved was Leonard Nimoy. Apparently, the only cast member to hold on to his dislike was "Scotty" James Doohan. Maybe; that could also be hyped. But it became apparent as co-appearances and co-interviews worked their way into the press that a real friendship developed between Shatner and Nimoy.

Now William Shatner, with David Fisher, has written a posthumous biography of Leonard Nimoy, Leonard: My Fifty-Year Friendship With a Remarkable Man. Let's see: 2015 (the year Nimoy passed away) minus 50 is 1965, the year that they began work on the promotional first episodes of Star Trek (they'd appeared in an episode of The Man From Uncle in 1964). As Shatner tell it, though, they were both accustomed to "show friendships" that last for the run of a series, and then end amid promises of eternal fealty. A real friendship was kindled once they were thrown together by the unexpected popularity of the Star Trek franchise in reruns, the conventions, and cemented while making the first movie in 1979.

It is apparent from Shatner's own telling of many stories, and his take on things he admits remembering differently from others, that the charge of arrogance is true, but he was not, is not, self-blind, and has a bit of a list of re-do's he wishes he could perform. However it happened, a real and even close friendship developed between the two men. They had similar backgrounds, were of the same age, and had worked equally hard to perfect their acting skills and develop a career. To get roles that some might call "lead and supporting", but were really co-leading parts, they had to be very accomplished actors by the time they were chosen for the Star Trek series.

With his somewhat brooding appearance and solemn manner (though not as solemn as Spock), before Star Trek Nimoy played the heavy or the villain about 2/3 of the time. Spock was not, as some suppose, his first "positive" role. As any actor will tell you, the villain's part is usually the most interesting, so he had developed a wide range of skills before he first put on the pointy ears to become a half-human First Officer on the Enterprise.

Without the book, it would be hard to gather all the elements of Leonard Nimoy's life, to see how remarkable he really was. As hard as he worked at acting, he also explored poetry and professional photography, and took time (but, he admits not as much as he'd like) to raise a family. The financial cushion of success and his "star power" after 1979 enabled him to finally "major in family". He no longer felt obligated to take every acting job that came his way. Like any other task he set himself, he worked conscientiously to heal the relationships with his children, who'd felt neglected and had drawn away. Perhaps this is why my favorite image of Spock is this stock image from the 2009 remake of the Star Trek movie, in which "Spock Prime" lends advice to his younger self. He has passed on, but while he was with us, he did indeed live long, and he prospered.

Finally! Some genuine Science Fiction

kw: book reviews, science fiction, space fiction, space flight, space aliens

John Campbell's recipe for a good short story (SF or not, but especially SF): "Pose a problem, and then solve it." The corollary for writing a novel: Do it 25 times. There was a period of a few years that I read a science fiction book, either novel or collection, almost every day. Then the genre began to change, and eventually even Isaac Asimov began to write more about sex than about science. "Hard SF" of the kind that characterized the Golden Age vanished. Fortunately, that couldn't last forever. For the past couple of decades, even as the library shelves formerly filled with speculative fiction were being taken over by sword-and-sorcery fantasies and post-apocalyptic dystopias, a few writers have been returning to imaginative technology as fodder for their work. I am thinking of post-1990 books by Stephen Baxter, Catherine Asaro and Ben Bova, for example.

This week I made acquaintance with work by an author new to me, John Sandford, and his collaborator, Ctein. The book is Saturn Run, and it is full of good ideas that are backed up by good science. I'll leave it to others to comment on how well the geopolitical US/China conflict is depicted. Geopolitics runs along a dimension I cannot "see". Among the new ideas, these stood out to me:

• A type of ion engine called VASIMR, VAriable Specific Impulse Magnetoplasma Rocket, has been on the drawing board for a while, and small ones were tested some time ago. Scale 'em up from a few watts to a few GW per ion beam, and you have a way to slowly thrust a vessel weighing a few hundred tons up to the kind of speed that can cross 1.4 billion km in a year or less. Let's see, 1.4 billion km / 31.6 million seconds = 41 km/s average. The authors ramp up to about 140 km/s and back down again, covering the distance in more like nine months. The "Variable" part is the genius of the engine. High velocity exhaust = high specific impulse, but has a poor momentum-to-energy ratio for accelerating from a stop to the "lower" velocities, less than a few km/s. So you get more oomph at the low end when starting out, and better high-end acceleration by ramping up the exhaust velocity as the ship accelerates.
• Conversion of electrical energy to thrust is stated as "not quite 50% efficient". Maybe by the year 2066 they'll be able to do better than the thermodynamics of Sadi Carnot, which fix a limit of 40% efficiency for any thermal-to-thrust system. Anyway, if you are using 8 or 9 GW to thrust the ship, you have another 9 GW or so of waste heat to dissipate.  In space, radiating heat away is the only option. A phase-change liquid-metal scheme, and certain ancillary tricks, serve to make a radiator that runs at 600 degrees and is "only" the size of a couple of football pitches, rather than the size of Chicago.
• First Contact is not with the aliens themselves, but with a conversational AI that can proctor certain trade deals to allow humans to obtain a limited amount of alien technology. This includes methods of making and safely storing usable amounts of antimatter for the next spaceship generation. Interestingly, the galactic civilization the authors present bases contact between species on proctored trade deals, strictly avoiding interspecies contact. It seems they learned the lesson that we have yet to learn from our own history of inter-cultural contact!

I did find myself wondering how much plutonium they'd have to carry to run a 20 GW nuclear reactor for a couple of years. The words "nuclear waste" never appear, but I suppose it was wise to put that issue off to a very different kind of novel.

Of course, science fiction is not just about purely technical matters. People are immensely variable, and authors play characters off one another regardless of genre. I was particularly impressed with the well rounded characters in Saturn Run. Sanderson and Ctein created characters that a reader cares about and feels for. I admire this in a writer. I've tried to write fiction, and found I have no proper feel for creating characters that are believable, likable, or that can induce empathy in a reader. The most sympathetic, at least to me, is a central character, Sandy Darlington, a paradoxical and hiddenly broken man, who manages to think of things nobody else remembered to take account of.

If I go on any more, I'll introduce spoilers. If you like SF that emphasizes science, yet with eminently human characters (even the AI!), this is for you.

Space Opera redivivus

kw: book reviews, science fiction, space opera, space aliens

Stephen King calls Jack McDevitt "The logical heir to Isaac Asimov and Arthur C. Clarke." Kind words indeed, but just a bit inflated. Nobody has yet come close to the more than 400 books written by Asimov, nor the breadth of vision and versatility of Clarke. However, McDevitt's 21 novels are nothing to sneeze at, and I greatly appreciate his fresh insights into alien species.

Starhawk is the 7th of the Academy series, also called the Priscilla Hutchins series after the protagonist. I read (and reviewed) the 6th volume, Cauldron, in 2008, but don't recall Ms Hutchins being particularly prominent.

In the Galaxy of the Academy series, alien life of any kind is rare, and aliens—so far located—bright enough to have language can be counted on one's thumbs and big toes. The brightest alien species is stunningly boring, but a series of a dozen or so "great monuments" shows that the Universe can produce beings of amazing power, but, apparently, less-than-amazing longevity.

In Starhawk the author explores two ideas of alien contact, one with an automated device that tells them they "just missed us", and another with an apparently planet-wide being that is helpful but indifferent: not hostile, but not interested in being visited long-term either.

The core of the action surrounds Ms Hutchins, who eventually earns the nickname Hutch. A newly-licensed starship pilot, she trying to start a career in a shrinking economy (2007-2012 writ large), in an era of increasing pressure to cut back the space program. Hard choices and a few untimely deaths provide coming-of-age experiences for her. Early on, I had a certain fellow pilot pegged as her eventual mate, but McDevitt outwitted me; the pilot dies attempting to divert a terrorist-controlled starship being used as an impact weapon.

The mix of hard science with just enough blue-sky stuff (like FTL) seems just right to me, and makes for compelling reading. It provides a canvas on which the alien contact stories, the exoarchaeology in which McDevitt likes to indulge, can play across the imagination. I wonder if I can find all five of the Academy books I've missed…

A Dyson hemisphere

kw: book reviews, science fiction, space fiction, space aliens, space travel

In their first collaboration, Larry Niven and Gregory Benford have come to lead that subgenre of Science Fiction that combines hard science, some blue-sky projections thereof, and believable sociology of both human and alien societies. In the case of Bowl of Heaven, the hard science keeps all speeds below that of light and accepts certain other known limitations of physics, the projections (or speculations) push engineering to the scale of a solar system and also posit a ramscoop that uses superconducting magnetic fields a few thousand times greater than any so far known, and the sociology involves a dozen or so humans confronted by not just one or a few quite alien species, but a profusion of them, in a colossal engineered ecosystem.

Most SciFi aficionados know the concept of a Dyson Sphere, the product of a society that captures all the radiation of a star as its energy source. Though Dyson first conceived of a hollow sphere, the concept was soon modified to encompass myriads of large, stellar-light-capturing orbital habitats in a thick shell about the star, sufficient to block all or nearly all of its light, and emitting waste heat primarily at wavelengths between 8 and 20µ (the human body's thermal radiation, at 310K, peaks at 10µ). So far, no deep-infrared stars suggestive of such structures have been observed. The orbital mechanics of such a system are formidable, and collisions might be so frequent as to make the scheme impracticable.

Niven's best-known foray into the partial Dyson Sphere arena has been the famous Ringworld series. Now we have an even more ambitious engineering project: Build a hemisphere centered on a flare star (a late K or early M star that tends to have a strong stellar wind), that supports many (quadrillions, I suppose) steerable mirror segments. Its radius is roughly an AU (150 million km). A wide ring at the equator supports a habitat with the area of many trillions of km², and the structure rotates to produce centrifugal "gravity" in the habitable ring. There is a hole at the center (the rotational axis of the hemisphere) with a special function. The mirrors reflect the star's light to focus on an area at the "rear" of the star (we can presume its axis of rotation), heating it and focusing its stellar wind into a jet that passes through the hole in the hemisphere. This begins to drive the star. Some sort of engines in the hemisphere counteract its orbital instability until the star begins to accelerate sufficiently to closely balance the tendency of the hemisphere to fall inwards. Then the job of the engines is quite a bit easier, or at least less energetic. Now you have a "ship" that is similar in size to the orbit of Earth or perhaps Mars, that can cross interstellar space over a span of millions of years.

This idea by itself could be fodder for a simple high-concept novel. For Niven and Benford it is mainly backdrop. Put it out there, make it a few tens of millions of years old, populate it with a cadre of large, birdlike alien species and an uncountable number of "adopted" alien species whose members they have plucked from star systems as they swung by in ages past. Then add US.

A ramscoop from Earth, bearing colonists heading for a star they've named Glory, catches up with this star-centered Bowl. Now, we all know that paying a visit to aliens who can engineer on such a scale is quite foolhardy. But it happens that the colonists, most of whom are in frozen sleep, have a problem. The small "awake" crew has discovered that the ship's top speed is a few percent low. Low enough that they can't keep a crew awake and alive long enough to get to Glory. They figure the Bowl might be able to supply them with materials they can use to replenish their stores, so they do pay the ill-advised visit, and of course the landing crew is partly taken captive and partly escapes to re-learn their Boy Scout skills as they flee hither and yon, evading capture while they learn what they can about the Bowl and the habitat.

I have wondered in the past just how big a spinning structure could be, to produce about 1g of apparent gravity. It turns out that the stress intensity for 1g of centripetal acceleration increases linearly with radius, such that the strongest known steel could not produce 1g when the radius is greater than a few hundred meters. Perhaps some kind of carbon nanotube assembly could hold together a structure of a km or so diameter. Both Ringworld and the Bowl would require materials with a tensile strength a few million times greater than any known. However, I was able to keep such considerations from marring my enjoyment of the book and its concepts, and I trust so can most SciFi readers.

A great deal goes on in this 400-page book, as we glean insights into the various cooperating "big bird" denizens and some of the Adopted species, and as one human group begins to learn to communicate with their "hosts" while the other searches for understanding and some kind of bargaining leverage. Here, the volume ends. I suppose a trilogy is planned (though the authors promise but one sequel, Shipstar).

The possibilities of quite distinct psychologies that the authors explore in the big birds are fascinating. Is our human Bicameral Mind going to be a handicap or a detriment, compared to their more unified psychology? It makes me wonder if the future volume(s) will explore the possibility that human psychology could become more unified, making our "unconscious" more consciously accessible.

There is a character, Fred, that I found myself identifying with. He is socially awkward but totally at ease with machines and computer code. In a conversation he describes his problem-solving technique, which takes advantage of sleep, and I was saying, "Yes! That's just what kept my programming career going for 4 decades!". I figure that either Niven or Benford must do this, or they know quite well someone who does and has described it. It is comparatively rare as an explicit technique, though many people have experienced waking up with a worrying problem solved.

Now I have my marching orders, to track the progress of the next volume, Shipstar, and any possible successor volumes. I can hardly wait.

Scattering planets like billiards

kw: book reviews, science fiction, science fantasy, space fantasy, space aliens, interstellar politics

The book is billed as "The explosive finale to the 'Ringworld' and the 'Fleet of Worlds' series": Fate of Worlds by Larry Niven and Edward M. Lerner. This is the latest, and allegedly the last, of twelve books in these two intertwined "Known Worlds" series, half of them published by Tor Books.

Exploding planets and vanishing stellar systems are "explosive" enough. So far Niven has not introduced an exploding galaxy. Such events take far too long for a human-scale story, anyway. Even when "human scale" has been expanded in the "Known Worlds" books to a few hundred years beyond the traditional three score and ten. Niven didn't invent "boosterspice" but he makes great use of it.

The whole series encompasses events between 630 and 880 years in the future, more or less depending on relativistic effects, such as for the fleeing Fleet of Worlds, six planets driven toward galactic north at 0.8c, for which Tw = 0.6To (calendar coordination is hard enough when your year is as long as mine!).

Where a typical novel has 3-5 important characters, this one has 25 or more (depending on how many downloads of Jeeves you count), 21 of them "natural" individuals, the rest being AI's. The core characters are Nessus, of a vaguely equine alien species called Puppeteers, and the humans Louis Wu and Sigmund Ausfaller.

The Ringworld is Niven's most famous idea, a detailed construct probably inspired by the notion of a Dyson Sphere. Ringworld circles its primary star at a distance of about 100 million miles, or 160 million km, filling the orbit. Its length is thus more than 600 million miles or 1000 million km; its width is a million miles or 1.6 mkm. Its mass is similar to that of Jupiter, or more than 800 times Earth's mass. In one of the novels it is shown that such a ring's orbit is unstable, so it has engines along its rim (with its multi-mile-high walls to hold an atmosphere) that periodically correct the orbit. It is home to tens of trillions of "sentients" who belong to an unknown number of nonhuman species, most of whom know nothing of any of the others. There is a lot of room in 1.6 quadrillion square km, even when a substantial percent is shallow oceans: Earth's area is 510 million sq km, counting oceans. Inward from the ring is a smaller, segmented one, that revolves on a different schedule, producing days and nights on the Ring. This one is also driven as needed.

Among a ton of interesting ideas, one that seems unique to Niven is the Protector: A post-sexual development of a sentient species, when fed an appropriate diet, a protector is hyper-intelligent and pathologically paranoid. A protector's mission is preservation of the species from all imaginable dangers, and they have incredible imaginations. As gadgeteers, they are super-Tom Swifts, super-Edisons.

Another is the Gw'oth, starfishlike aliens that can link nervous systems via sockets in the ends of their five "arms" (tubercles in the story), to meld into group minds. A 16-fold meld in a hypercubical configuration is formidable indeed. One such group mind is found to be the power behind the "power behind the throne" of the Puppeteer planets.

The book weaves together numerous strands left hanging by all those that came before, returning not only Wu, Ausfaller and Nessus, but a number of other protagonists to a place of stability, if not honor. Considering that they all have used variously dishonorable means to accomplish their prior feats, that is no mean bit of writing! The drama begins when Ringworld vanishes, leaving a hyperspace- and gravitational ripple which rocks detectors for a considerable distance. It ends when a few planets also either explode or take flight; it seems someone has cracked a conundrum of hyperphysics relating to the behavior of a "spacecraft" deep in a gravitational well. There is a little fodder here for Niven and Lerner to continue the series should they so desire. I wouldn't mind.

A crystal future?

kw: book reviews, science fiction, space aliens, artificial intelligence

Like many, I have a lively interest in the possibility of other sentient species throughout the Universe. I have supported the SETI program for decades, including running the seti@home "screen saver". More recently, I have vetted a few thousand stars' light curves for the Planet Hunters project; I noted this morning when I checked in that there are 666,916 participants.

However, as a radio amateur, I realize how unlikely it is that SETI will turn up anything, even if there are millions of inhabited planets "out there". Our term as a radio-loud species lasted barely 100 years (it is all on cable and glass fiber now), and even though some TV stations of the 1960s-1990s utilized million-watt transmitters, even the Arecibo 300 m radio telescope would be unable to detect I Love Lucy or Jeopardy at a distance greater than about 10 light years. An intelligent species 100 to 1000 light years away would need to do one of two things to produce a signal we are capable of detecting: point a gigawatt signal right at us using a kilometer-scale dish, or broadcast an omnidirectional signal with a power of billions of gigawatts. Both are costly undertakings.

An economic analysis that I read a few years ago compared the cost of a huge radio transmitter to the cost of sending a number of small (around 10 kg) objects, propelled at about 1% of light speed, carrying some kind of message. The hard part is for such a small object to carry a technology for slowing down at the other end! One percent of c is about 100 times the velocity of Earth as it orbits the Sun. That's a lot of kinetic energy to shed.

This is the kind of idea a science fiction writer can run with. Couple it with likely developments in computer technology, possible advances in artificial intelligence, and a few projections—or flights of fancy—about human society, and a book like Existence by David Brin emerges. A very enjoyable book, I might add.

Some 40-50 years in our future, with a planetary population of 9 or 10 billion who are apparently all networked into the MESH (successor of WWW), an effort has finally been undertaken to clean up the mess left behind by NASA, ESA, and the various Soviet and Russian space agencies. With tens of thousands of broken satellites, shed fuel containers and bolts and bits of exploded stuff, near-space is getting hazardous. A trash-collecting astronaut named Gerald snags an unusual crystalline object, so rather than nudge it into an Earth-intercepting orbit, he retrieves it, at some risk to his career. When Gerald and the object return to Earth, he touches it, whereupon a word appears—a lot like the way a magic 8-Ball toy's message floats up—: Greeting.

So, as usual, the author leaves it up to the brains in the alien machine to figure out how to communicate with us. In an already big book (553 pages), this does avoid a large digression, so I can forgive it. Anyway, you might ask, is this the only one? No, as it turns out, and something like half the book is taken up with the consequences of finding multiple crystal ovoids from competing species, now that people know what to look for. Yes, the aliens are competitors. A peaceful Galactic Federation is about as likely as a one-world government here on planet Earth, or even less so. Star Wars trumps Star Trek.

I won't go further along the plot line. There are too many other fascinating threads to this story. Much is based on continued increases in becoming one with our computers. All but the very poorest (there is still a bottom few percent, more's the pity, but I am not surprised) have access at least to TruVu specs that let them access the many levels of the MESH. The software in the specs takes its cues from where you focus your gaze. Many, particularly the younger folks, get equipment installed in their vocal chords and teeth, and wear intelligent contact lenses, so they can effectively live in the MESH and control it with subvocal commands and tooth-taps and eye-flicks and hand motions. (Let it be noted, fifteen years ago I predicted to friends that "soon" people will be able to get a smart cell phone—the "smart phone" had yet to appear—implanted in the mastoid bone, attached to a tiny microphone in the jaw and a tiny speaker in the wall of an ear canal; it would respond to spoken or muttered commands. Maybe "soon" still means another 20-50 years…)

True artificial intelligence has yet to arise, but Brin's 2050s society has a close simulacrum, that can pass the Turing Test if it doesn't go on too long. Allied words have been coined, such as maind, aiware, aitomatic, aissistant and ailectronic. A brief vignette, wherein a high school student manages to download the personality of her pet rat into a computer, sets the stage for the crystal ovoids to contain numerous downloaded personalities. Then there are new acronyms. My favorites are WAIST (Wow! Ain't It Strange That…) and TSOOSU (To See Ourselves as Others See Us, and the command tsoosu invokes a MESH view of oneself from nearby cameras).

Here is an idea for someone capable of writing it into a novel: a possible process for capturing someone's personality in software. A backpack containing a massive neural network with heuristic programming, plus a "sensor hat" you would wear. Other sensors on or in the body are possible, but I haven't thought that out. You would wear the equipment for a few weeks or months, while it tries to learn to predict your behavior from the stimuli you encounter, plus periods during which you explain your behavior to the backpack. I suppose a breakthrough would occur at some point, and thereafter the longer you wear the equipment the better the simulation gets. How good you want it to be depends on the purpose to which it will be put. Once created, the simulation is easily copied. This would probably work best with people who have a lot of toleration of solitude, because such a simulation of your personality is most likely to be used to control a machine with a dangerous or one-way mission, including a small interstellar spacecraft.

That brings us to another interesting thread: Auties, a slang word for autistic people. Might it be that, for those who don't communicate, their only possible mode of communication is not words but something else, such as dance or broad-spectrum sounds packed with more meaning than our "words"? Brin treats at least some Auties as an evolutionary advance or even the vanguard of a new human species, one with immensely greater problem solving skills than run-of-the-mill geniuses.

Last evening I heard Sher Valenzuela speak to the Republican National Convention. Her son is autistic. She and her husband started their business, 15 years ago, in hopes of earning enough money to afford the specialized therapy their son needed. They succeeded. He is soon to be a sophomore in college. It would be amazing if such children had untapped potential and we could somehow learn to bring their abilities to fruition. In Brin's story, ubiquitous computer technology makes this possible. In our world, today, I dare not offer such hope, not yet. We know so little… I do know this. The two best computer programmers I ever met are autistic. I don't mean they have Asperger's syndrome. They have much more trouble communicating than my friends who have Asperger's. They have machine-like minds, and have said that dealing with people requires them to run a sort of social simulator program in their heads, which takes a lot of effort.

Another thread, a less encouraging one, is the Trillies, the trillionaires who scoop off about the top third of all human productivity for their pleasures and hobbies. There is a hint near the end of the book that their influence is abating, by the year 2100 or so. Really, what possible good comes of having billionaires and trillionaires around? I know one billionaire. He is a nice guy. But is the Earth better off if he owns, like, one percent of its land surface? The billionaires and some other celebrities are the new aristocracy. They would do well to beware, and learn from events such as the French Revolution.

When I worked at Conoco, the Marland Museum had a placard with a quote of E. W. Marland, founder of Marland Oil and then Conoco. As I recall, it says, "Who knows why people do what they do? I spent money like water on my town and my people, and they prospered." Let us remember that the money "he spent" was originally earned by those people in that town. My supervisor's and manager's salaries—and right up to the CEO—comes from money my colleagues and I bring into the company, which is not paid back to us but to them. The work that they do does not earn money directly, but rather produces the environment for us to earn the money. If they do it well, they deserve just compensation. I don't believe, however, that there is a person on the planet whose work is worth more than about half a million dollars per year (my CEO earns a million a month).

Finally, I was very intrigued by a list of twelve detailed questions, directed at Lurkers, possible alien AI objects in our solar system, as to why they have kept silent all this time. Think about it. If self-replicating Von Neumann machines are the least expensive way to communicate with the Galaxy, and it would only take 5-10 million years for such devices to spread to every star, multiple times, then where are they? Is the human race truly the only intelligent species? Two books explore the boundaries of this question: Vital Dust by Christian DeDuve and Rare Earth by Peter Ward and Donald Brownlee. But before you read them, read Existence.

Searching for fellow citizens of the Universe

kw: book reviews, nonfiction, biographies, exobiology, space aliens

Take a look at this artist's rendering of the Milky Way galaxy. The yellow and blue circle left of center represents the volume that can be reached with the SETI listening program, with a radius of about 200 light years (The new kilometer-scale array ought to increase that, at the cost of fewer simultaneous targets). Using an accepted scale height of the main disk (the spiral arms) of 1000 light years, or an effective thickness of 2000 ly, and a radius of about 50,000 light years, the (very rough) effective volume of our Galaxy is about 16 trillion cubic light years. The SETI listening volume is four million cubic light years.

To date, after listening very hard to one four-millionth of the Milky Way ("the Galaxy"), we have not recorded any radio signal from any other civilization. If, as Carl Sagan believed—and he has plenty of company—there are about a million alien civilizations in the Galaxy, there is about one chance in four that one of them is in range of the SETI program, to date. With one proviso: that "they" are broadcasting a signal quite a bit stronger than our own radio and TV "spill".

Further, megawatt TV broadcasting began in the 1950s, and will soon come to an end. Nearly everything is now on cable or glass fiber. I suspect any aliens out there also discovered ways to get their entertainment without using megawatt broadcasting, in less than 100 years, as we have. And by the way, now that TV and much radio is digital, and compressed, with suppressed carrier technology, if anyone "out there" detects our more recent signals they won't be able to decipher then, unless they have stumbled upon exactly the same MPEG and framing standards that we use. Our signals may as well be encrypted.

Carl Sagan didn't create the SETI program, Frank Drake did. Sagan had too much else to do, but he and Drake were friends, and Sagan was always a friend to Drakes' radio listening programs. In 1975 the two went to Arecibo Radio Observatory in Puerto Rico and listened for any signal from the Andromeda galaxy. They were hoping, if there are a million civilizations in our Galaxy, there would also be a million in the even larger Andromeda galaxy, and perhaps at least a few of them employed multi-terawatt radio beacons. Maybe one would be pointed this way? They didn't detect any. Actually, even listening with the 300 meter dish at Arecibo, it would take an alien beacon with a trillion trillion watts to punch a signal this far.

Captured by Aliens: The Search for Life and Truth in a Very Large Universe, by Joel Achenbach, was published in 1999, nearly three years after Carl Sagan died. It is in part a biography of Sagan, but even more, it is a chronicle of belief in extraterrestrial aliens throughout the United States. We find two attitudes toward the existence of alien civilizations, either "Of course!" or "Of course not!!". Very few people are indifferent or neutral.

Sagan was unusual. Though he passionately believed that there must be someone else in the Universe besides us, he was a scientist through and through (and often rather a jerk about it). This made him what Achenbach calls the Gatekeeper. As a very public, very popular astronomer and popularizer of science, he received tens of thousands of letters (and later, e-mails), frequently with someone's grand idea: how to go faster than light or travel in time (they come to the same thing), or for anti-gravity devices, or for ways to detect "the aliens among us", or about UFO's and government conspiracies to conceal their existence, or from people who believed that they themselves are aliens. As much as Sagan wanted to believe at least some of what he was told, he always checked an idea out scientifically. Thus, he had no truck with New Age and spiritualistic approaches.

His desire was his Achilles Heel. Achenbach notes that, time after time, often in a public forum, Sagan would bring himself to the edge of some looney position, only to swerve away at the last moment. He was an expert at having second thoughts, which usually kept him out of totally going bonkers.

Not so for many others. During the near-decade of research for this book, Achenbach attended a wider range of conferences and seminars on the general theme of "alien studies" than we might imagine could even exist. Of course, he was in Roswell, NM for the fiftieth anniversary of the alleged "flying saucer" crash in July 1947 that made Area 51 famous, and jump-started the fame of Major Jesse Marcel. Marcel's description of the materials as being unlike anything from Earth got into the news, and stuck in everyone's memory. Marcel's son is still a popular figure at "flying saucer" conventions. Twenty-odd years of study by the Air Force, culminating in Project Blue Book (terminated 1969; I remember that), just fed into the conspiracy theories of the suspicious.

But the real stars of the book are not the conventions so much as the conventioneers, the many people with a huge spectrum of beliefs. This says more about us than about aliens; in the absence of any clear evidence that any aliens exist, it is impossible to actually say anything about them! Humans want to believe. In spite of the rise of science, half or more of people in Western cultures still believe in a god or God of some sort (Elsewhere, it is much more than half). For many avowed Atheists, their aggressive non-belief is a religion in itself. And for many, science has become Science, a religion in its own right. Here again Sagan shines. He was never willing to call himself an atheist. I suppose we would call him an agnostic, one who "doesn't know", but he didn't use that word either. Stephen Jay Gould was the most adept at answering belief questions, whether about God or aliens: "No data."

There is an interesting journey among the ranks of "abductees". Achenbach is himself subject to sleep onset paralysis. All of us (except sleepwalkers) have our muscular system switched off just as we go to sleep. For some people, it sometimes happens a few minutes earlier. It can be terrifying. Fears are amplified, and hallucinations are frequent. I have a related "condition". When I am tired enough to be woozy, simply closing my eyes is enough to start a dream, even though I am mostly awake. I frequently hear voices in this state, but I can tell I am dreaming, and it stops immediately if I open my eyes. It is probably related to what schizophrenics suffer; they can't shut it off so easily. Sleep researchers consider that all "abduction" experiences have sleep onset paralysis as their source. Lots of people disagree.

During the final chapters, Achenbach takes a journey in a more spiritual direction. Not that he is a spiritual person, but he saw how many people, when faced with evidence that contradicted their belief, or especially when there were simply, "No data", would respond, "But I feel it is so." This is equally true of the "Of course not" folks, and some have gone to the extent of producing statistical analyses of how long our own civilization might last (one published paper states from 7,000 to 7,000,000 years, with "90% certainty"), or of the probability that "anyone" might be "out there". Strangely, even the most anti-scientific of the "I feel so" crowd want some sort of scientific patina upon their belief system. I say, if you aren't going to take science's answer, at least be honest that your position is based on something other than science.

In one section near the end, he recounts and updates the stories of some of the people he has written about. I just had to look up a few of them to see how they have fared in the thirteen years since:

• Frank Drake, now 82 and Chairman Emeritus of the SETI Institute, continues active work with SETI. He has been at it for 52 years.
• Jill Tarter, who worked with SETI nearly as long, recently retired from active service to go into fund-raising for ongoing SETI programs.
• Dick Joslyn, who left the Heaven's Gate cult a few years before they suicided, died of Aids in January, 2000. Achenbach interviewed him for a chapter on the cult and "alien cults" in general.
• A facilitator of Starseed (a group who think they might be aliens), Miesha Johnston continues the weekly meetings, and also holds meetings for abductees, or those who think they might have been abducted. Her former friend Jan Bingham, who really thought she was a Pleiadian, seems to have dropped out of sight.
• Dan Goldin, who was NASA administrator from 1992 to 2001, a strong advocate for a human space program and for searching for extraterrestrial life (but mainly focused on bacteria), is presently involved in robotics research.

This could be seen as a sad book. We don't know anything more about aliens, or ETs, or whatever, than we did in 1947 when pilot Kenneth Arnold reported seeing nine shiny objects that moved "like saucers skipping on water", and estimated they were moving about 1,200 mph (1,900 kph). We really haven't progressed since the time of Ezekiel, who saw "a wheel in a wheel" with a rim "full of eyes". He was probably reporting a dreamlike vision, but a lot of people think it was an alien spacecraft. These have never been explained, nor have many, many other unusual sightings and experiences. Like Achenbach, I'd like to see a spacecraft land and someone come out to greet us. Failing that, a radio or light signal that clearly comes from off-planet (at least, farther away than our Moon), and not from one of our own Pioneer or Viking robotic craft.

Note, Pioneer Ten's transmitter used 8 watts until it was shut down in 2003. It was barely detectable from 67 AU (an AU is 149 million km; a light year is 63,500 AU). Pioneer used a directional antenna, but I don't know its gain. This implies it would take a signal of 7 million watts to be detected at a distance of one light year, and about 80 million watts from the distance of Alpha Centauri (or a lot larger antenna and "only" a few million watts—and it would have to be pointed right at us). Out at 200 light years, based on 7 million watts at one light year, an alien would have to really want to get through to us: it would take 280 billion watts with the Pioneer antenna, or at least 2-3 billion watts with one that had 100x the gain (about the size of Arecibo's dish). We are not going to hear anybody's accidental, unfocused signal at stellar distances. We just aren't.

I have to agree with Joel Achenbach's conclusion. We detect ourselves. We project our own hopes and dreams and fears and loves and hates upon imagined aliens. Yet we don't know whether dolphins or whales or apes or octopi have languages. How will we ever learn to understand a form of life that didn't originate here?

Tangling with the wrong crowd

kw: book reviews, science fiction, future fiction, space aliens

Joe Haldeman, who achieved fame with his Forever War series, takes up quite a different tack with his recent Marsbound novels. Marsbound was followed by Starbound, and now by Earthbound. The novels are set some 200 years in our future.

In this third novel, the meaning of "bound" shifts. In the first two, humanity was bound for Mars, then for the stars. Here, they are bound to Earth. The Others, greatly superior beings from 25 light years away, were discovered to exist in the first novel, and contacted in the second. They have imposed limits on human expansion, first by blowing up the Moon into a planetary shroud. When the American president ordered a shielded rocket to launch anyway, the Others shut off the power—a source of "free energy" that had only recently revolutionized the global economies. Then they went further to prevent all electrical machinery from working. Electrochemistry seems to still work, so brains have not shut down!

The novel carries Carmen, the heroine of the first two novels, through a few weeks of adventures on a world of eight or nine billions suddenly thrust into the Nineteenth Century. Actually, for most people on Earth, I would not expect the loss of electricity to have much effect. They are still living in the Sixteenth Century. A lot depends on how far "Western" technology spreads in the 21^st and early 22^nd Centuries.

It is hard to say too much without giving the story away. As you might expect, in a total collapse of society, money becomes valueless, and the greatest worth is now placed on food and ammunition. Much of the excitement of the book is set in a few pitched gun battles, in which Carmen learns to shoot, perhaps to kill. The book ends with a transition, so the author has more novels planned. Why should he stop with a trilogy? The fashion these days is to go on for five to seven volumes. In particular, in the closing chapters it is not even certain just how advanced the Others are, and whether humanity can come to terms with them on any kind of useful basis. I'll stay tuned.

Two-headed camels and starfish superminds

kw: book reviews, science fiction, space opera, space aliens

I gotta hand it to Larry Niven, he comes up with interesting alien races. While Betrayer of Worlds, written with Edward M. Lerner, is not the first novel in which the Gw'oth appear, it has the first extended treatment of their culture. A Gw'oth looks like a starfish, as they are aquatic and are built of five "tubacles". Certain groups of them—I am not sure if all are supposed to be capable of this—can merge together as 4-fold or 8-fold or 16-fold assemblages with nerve connections that allow them to work as a combined intelligence with a new name and identity. In a 16-fold configuration they can solve four-dimensional problems and generally out-think the best minds known to both human and "citizen" (i.e. puppeteer) species, and even perhaps the Paks.

Betrayer of Worlds is a prelude to Ringworld, and fortunately is quite free of the vulgarity found in it. While much of the action revolves around the genius Louis Wu and his citizen patron (friend is too strong a term) Nessus, and their conflicts with deranged citizen Achilles, I found most interesting the way the authors imagine the cultural and political life of the Gw'oth.

The citizen Fleet of Worlds, five planets fleeing the galaxy and a galactic explosion, is flanked fore and aft by the Gw'oth home planet and a colony planet further out. The colony is actually a rebel world trying to escape the totalitarian influence of the home world, led by the 16-plex mind named Ol't'ro. The rulers of the home world and their disgust for multiplex minds are well portrayed. A few multiplex minds, in particular one 8-plex, are tolerated because they are useful, but are held prisoner.

The excessively paranoid Achilles has fomented war with the Gw'oth, misunderstanding their civil war as an invasion, and it takes the combined cleverness of Louis and Nessus, plus cooperation with Ol't'ro, to forestall open warfare and even genocide. Ol't'ro is the wild card here. It maneuvers Achilles into leadership of the citizen worlds, where he can be manipulated to its will. The novel ends about fifty years prior to the events related in Ringworld.

I felt compelled to determine the energy budget of the species involved here. The Fleet of Worlds is moving at about 0.5c towards galactic north, and is still accelerating. The kinetic energy of each of the five planets (and a sixth, New Terra) is around 10⁴¹ Joules. This is about seven million times the yearly solar luminosity, which makes the citizen/puppeteer species a Level 3 species in my informal taxonomy of spacefaring species:

• Level 0 - muscle power only.
• Level 1 - fossil fuel and stationary fission plants. Planetary energy budget at least 10²⁰ J/y. Earth is in this category.
  
• Level 2 - fusion energy. Planetary or species energy budget at least 10³⁰ J/y.
• Level 3 - fusion and perhaps antimatter. Energy budget at least 10⁴⁰ J/y.
• Level 4 and higher - antimatter control including stellar annihilation. Inconceivable energy budget.

I can imagine these things, but I don't know if they are possible. It seems the citizens don't utilize antimatter, but deuterium is mentioned several times. It takes a lot of deuterium to generate 10⁴² Joules; several stellar masses of deuterium.

I like the writing of these two authors together better than Niven's earlier collaborations. I understand this is not their first, so I have some catching up to do.

The limits of human enhancement

kw: book reviews, science fiction, space fiction, space aliens, space warfare, battle suits

In Cobra Guardian, the second book of the Cobra War trilogy, Timothy Zahn presents not one, but two ways to make a super-warrior. The drama revolves around Cobras, men and women implanted with servomechanisms for extra strength and speed, enhanced senses of hearing and vision, and a variety of laser, electrical and sonic weaponry. These make a single Cobra roughly the equivalent of an Abrams tank. It required the might of hundreds of Cobras to defeat a warlike branch of the Trofts, some of whom are more inclined to get ahead by trade and treaties, while others prefer conquest. The Tlossies are a Troft demesne of traders who are allies of humans, but reluctant to go to war against other Trofts on our behalf.

A sometime rival planet of humans, denied knowledge of Cobra technology, has developed warriors they call Djinni, who wear external robotic strength-enhancing and sense-enhancing technology and weaponry that makes them quite equal to Cobras, and in certain ways even more deadly.

In the middle of the mix is the planet Caelian, which has fascinating biology. In a ramped-up Darwinian system, the plants are bad enough, but even the mildest animals are downright nasty. "Flossies" look a little like sheep, though their curly pelt is more like steel wool. A large contingent of Cobras is required to guard the ordinary humans on the planet, a never-ending assignment.

On the other four planets that host Cobras, though, they are seen as anachronisms. It has been a few decades since the warlike Trofts were beaten back, and they are being seen as an unneeded expense. Politicians argue "austerity measures" that include cutbacks in Cobra funding. Then Troft warships attack all five Cobra-bearing planets.

As it happens, unknown to the Trofts, automated surgical machinery has been developed that can reduce the time needed to augment a human to Cobra in five days, and in another breakthrough, cognitive-enhancement drugs enable them to be trained in just a few more days. If the allied worlds can beat back the Troft invasion long enough to produce a few hundred new Cobras, they can win this phase of the Troft wars.

I was most fascinated by the extreme biology of Caelian. It is a wonder anything stays alive. Wind-blown plant spores turn any organic material into a green forest of rapidly-growing, and carnivorous, plants. That includes the clothes you are wearing, but fortunately not your own skin (while you are alive). Once a few plants take hold, insects follow, and they all seem to be hungry for blood. Bigger animals follow the insects, and if you don't keep the plants scraped off your clothing, you will soon be eaten by the bigger bugs and their predators. Then there are the larger predators; anything over ten pounds in size will gladly take on a human.

The humans on the planet have developed a silicon-based fabric called silliweave that denies the plants a foothold, as long as they keep plant spores wiped or scraped off it regularly (blown-in dirt can feed the plants—and it is always windy). That's a chemical technology I find interesting. What they really need is some way to keep the plant spores from gaining that first foothold, even if a little dirt has blown onto a garment. They are working on that…

I find Caelian more plausible than Cobra or Djinn, however. The energy source for their acrobatics is left unstated. An armor piercing laser hidden in a leg bone (or alongside it) needs to dissipate a few megawatts, if briefly. Even a "fingertip" laser that can zap mere mortals will cook the finger in which it operates. And jumping ten or twenty meters, straight up? I'll wait until I see it. Of course, these capabilities make for some truly rollicking fight scenes.

The book ends with an opening for Cobra Gamble, due out in another year or so. In that book the author will have to bring together all the threads laid out so nicely for us in this one.

Half a thumb up

kw: book reviews, science fiction, space aliens, jupiter, political drama

A few years ago (before I began this blog) Ben Bova released Jupiter, a space science tale about finding big (mountain-size) creatures slubbing around in Jupiter's planet-spanning ocean. There was a hint that they may be intelligent (i.e. able to communicate), which left an open path to a sequel. The sequel has arrived: Leviathans of Jupiter.

The book is big, 477 pages, and large parts of it are full of overdrawn political intrigue that simply bores me, so I read the first and last hundred pages. The primary good idea here is that the big Jovians communicate by sight. They are like deep-sea squid, with light organs that function like a display screen so they can communicate with pictures. I recall a story set on Earth in which giant squid can make intelligible pictures in a similar manner. I don't know if Bova got the idea from that…or even perhaps he wrote that one, also!

The plot boils down to a group of scientists proving that these "Leviathans" are intelligent enough to communicate with humans sent among them in a giant submersible that has multiple hulls so it can survive to depths exceeding a thousand kilometers under a gravity of about 2.5 G's. The humans attempt communication with a kind of brain probe, but this fails. Instead, the light display method turns out to work best.

There is, of course, a villain, a ruthless woman who believes the lead scientist at the Jupiter research station is competing with her for presidency of the International Astronautical Authority. She is prepared to destroy him and his program, and kill a few people along the way, to meet this perceived threat.

I have experienced growing unease these past ten or twenty years with the poor quality of the political conflicts in Sci-Fi in general. It seems there has to be a villain who is totally and irredeemably bad. It took me many years to understand that most of civilization is an attempt to manage the conflict that naturally arises because everyone, meaning everyone, is partly right and partly wrong, always. Most political conflict is between people who mean well but have different priorities, well leavened with the law of unintended consequences. As Bobby Burns wrote, "The best-laid plans o' mice and men gang oft agley." (gang agley being Erse for "jump the tracks").

I suppose Sci-Fi writers like black-and-white stories better than shades-of-gray. Too few realize the rainbow of "mostly good" sociological attitudes that must be accommodated to make any workable compromise. But who can blame only the authors? It is what most readers also prefer. In my experience, most of those who enjoy Sci-Fi, myself included, are more comfortable with machines (predictable mechanisms) than with people (messy and unpredictable). So we want our heroes to be wholly, even painfully, good and our villains to be completely evil. But I write "our" as a partial distruth, for I am no longer satisfied with such polarization. I've always likes stories better when people were pitted, not against an evil adversary, but against an uncaring Universe, and needed better knowledge and better engineering to overcome its obstacles. And those few stories in which people of different viewpoints had to collaborate to "work it out" are most satisfying.

In Leviathans of Jupiter, the story of overcoming the extreme pressures of the deep Jovian ocean, and the alien mind-set of its denizens, held plenty of interest for me. Not only do I not need the villain, I found her distracting. She was too evil to be plausible, and too easily overcome to be worth the reading, which is why I skipped more than half the book.

These dogs don't have their day

kw: book reviews, science fiction, space aliens, alien invasion, alien empires

It took Out of the Dark by David Weber a while to get going. There were several plot lines to establish, and I got a bit restive at first. Once the setup was out of the way, however, the book was a fast read, with plenty of action.

Consider a galactic web of civilizations that began over 70,000 years ago. In contrast to many space operas that are peopled mostly with humans in animal suits, this author's universe is full of bovines, on the premise that carnivores and most omnivores will bomb themselves to oblivion as soon as they invent nuclear weapons. At the beginning of the novel, set some 600 years ago, this planet is designated a Level 6 civilization, just a step or two up from spear-throwing savages. Then, in our near future, an aggressive doglike species, the only starfaring carnivores, are given permission to colonize Earth, as little progress is expected. These Shongairi, familiarly called "puppies" by humans, come expecting an easy takeover, but are surprised to find a Level 2 civilization has developed with unprecedented rapidity. They decide to take over anyway.

When you have the advantage of altitude, thousands of miles of it, you don't need advanced weapons to "soften up" a planetary target. Simply drop big rocks on it, which will come in like meteors and destroy with the force of megatons. So the puppies do just that, after stealthily hacking the loosely-defended Internet and the military computer systems connected to it. Having determined where most of the military resources of all major nations are, they destroy these in a matter of hours. Then they send in a force of 24 troop-carrying shuttles, and are aghast to find that these are destroyed in a sudden, five-minute attack by four fighter aircraft.

Things go downhill from there. We are so good at fighting one another, that turning against an alien invader is almost second nature. The puppies have never before tried to subjugate a Level 2 planet, and they find they've bit of much more than they can swallow. Finally, the Shongairi decide to create a super-virus and destroy the human species. At this point, humanity is found to have one more ace up its sleeve. To avoid totally spoiling a good read, let me just say that it originates in Romania.

An element that I like is that the invaders find a most peculiar (to them) element of human psychology, which is the secret of our fanatical fighting prowess: family values. We'll do anything to protect the family, and seek any revenge if they have been destroyed. Even among mammals on Earth, humans are peculiar in the intensity of our family attachments. Most animals will sacrifice their offspring if they must, pragmatically expecting to give birth to more. Humans are nearly unique in assigning to their living offspring "the future of the species." Animals consider only sunk cost; people consider future potential.

Of course the book is human chauvinist. Do you think an author could sell books about the defeat and extermination of humanity? It is nice to think we really could force the retreat of a seemingly superior race of aliens, even if they had thousands of years of head start. I wonder, though, whether the first aliens we meet will be more like millions or a billion years ahead of us. At such a juncture, I am not sure "meeting" is possible. Could we notice one another? It is not certain. So a comfy universe with a "mere" 70,000 years of sentient history is an easier concept to swallow (Actually, thinking it over, the aliens' "standard year" is twice an Earth year, so it is more like 140,000 of our years. Ho hum).

One of my tests of a book is how many hours of sleep I lose, reading half the night or more. Once it got going, this one ranks up there among the top page-turners of my experience.

The other is a mirror to ourselves

kw: book reviews, science fiction, space fiction, far future fiction, space aliens

I thought long and hard about how much to reveal of Echo, Jack McDevitt's latest space opera. Humanity has been in space 8,000 years, traveling hundreds of light years takes less time than driving from Florida to California, and a moderately wealthy antiquities dealer named Alex Benedict can afford his own starship. In eight millennia of looking, only one sentient alien species has been discovered, and they are called the Mutes, for reasons never detailed in this novel. Beyond that, I'll come down on the side of dealing in ideas, not in story plots.

The central thought is expressed by a comment made by a minor character. Faced with a cosmos nearly empty of Others, humanity is faced with only the "echo of themselves". And Echo is the name chosen for a stellar system upon which a mystery rests. Suppose we achieve star travel, look everywhere, and find that we truly are alone. Then what? The question that informs this tale is, yes, one other alien civilization has been found, but no others: Now what? Does that make our existential angst worse or better?

To the quintessential businessman, everything is business. A travel agency CEO becomes the villain of the piece, but like my thoughts on, "Does the Devil know he is evil?", author McDevitt has a quote opening one chapter that begins, "Truly evil persons do not recognize their own malevolence." It is attributed to Tao Min-wa, whom I cannot verify, so it may be a "future quote", as several are in the chapter headings. But I like finding an author whose thoughts echo my own.

Throughout the book's quest, Alex and his assistant Chase are dogged by the attentions of a hired killer. Chase becomes the hero who eventually thwarts the assassin, just as she is nearly the first victim. I was reminded of old "Assassin's Guild" cornball routines. This requires a digression.

When I was in college, forming a non-lethal Assassin's Guild was a popular pastime. People would think up creative ways to do someone in, then act them out with harmless props, like a pillow instead of an anvil to be dropped on someone's head. One of the spy series that was popular on TV at the time took up the theme in one episode, which opened with someone actually getting killed in an AG sort of way: a cartridge had been secreted into a telephone handset, which went off when a tuning fork of a certain pitch was struck, killing the person who'd answered the phone. The creativity theme was carried along for a while, but when it came time to bump off the hero of the series, all these creative people grabbed pistols and began running around almost like a Keystone Kops version of guerrilla fighters. It was hilarious!

That is how I felt here. The killer's first attempt was overly elaborate, and requires readers who don't know any science: A lovely artifact arrives in the mail. It is stated as being the size of Chase's forearm, so it's no more than a cubit in length, about half a meter. When she sets it upright, lights come on inside, but then she begins to suffocate. Turns out it is sucking the oxygen out of the room. She gets rescued of course. But an explanation is offered that ruins it. The object is said to be filled with powdered magnesium and there is also a battery-operated cooling device. When the magnesium gets cold, it quickly absorbs oxygen.

There is a limit to the amount of disbelief I can suspend. I know enough chemistry to realize you can't get cold magnesium to absorb anything. It is a flammable metal, and the oxidation of the metal is ferociously hot (I've done it). A magnesium flare is the brightest one there is! Chase would have run for her life, not stayed around long enough for the oxygen level to drop. Further, there is more oxygen in a room than one might imagine, plus, Chase is told the device removed the oxygen from the whole floor of the house.

Let's do a little math. Under ordinary conditions, near the temperature and pressure a scientist calls STP (the S is for standard), air weighs about 1.28 grams per liter (g/l). Twenty percent is oxygen, or 0.256 g/l. An ordinary living room contains about 50 cubic meters, or 50,000 liters. The oxygen in that volume weighs 12.8 kg. A magnesium atom combines with one oxygen atom, but weighs 1.52 times as much, so absorbing 12.8 kg of oxygen requires 19.5 kg of the metal powder. That is upwards of forty pounds, something Chase is unlikely to be able to lift with one hand. And what about that bit that the whole floor of the building was deoxygenated? A modest house's first floor has a volume greater than 200 cubic meters, contains 50-60 kg of oxygen, which would require 75-90 kg of magnesium. So, that's two strikes against this idea. The chemistry won't work, and the mass of reactive metal would be much too great.

The other brainstorms attributed to the hired killer are at least remotely plausible. And in the end, a "proton cannon" is used. The range of energetic protons in air is about a meter, so you have to get the cannon rather close to its target. In this story, it seems to have a greater range... Oh, well, just like in the spy story, when you really gotta kill someone, may as well use a gun.

Businessman plus hired killer. That's one element. There is the true believer, an explorer who spent more than a century looking for aliens and didn't find any. There are two people who, added to Alex and Chase, make this a double love story. And Alex and Chase themselves, what drives them? They are two faces of an ultimate realist, one who wants to know the truth, regardless, one who wants to get it right.

Now I must back off and say I really enjoyed the book. The author is a compelling writer, and the basic ideas kept me thinking throughout. I tend to swing back and forth between Fermi's question, "Where is everybody?" and, "When we get out there, they'll be everywhere." Maybe civilizations are rare "out there", but I can't imagine they are so rare that we are the only one in our Galaxy (we have little hope of ever communicating with anybody in another galaxy). The question asked by this book is, "But what if we are?"

Where are they, indeed?

kw: book reviews, nonfiction, radio astronomy, space aliens

Fifty years and counting. In April 1960 Frank Drake first listened to space using a radio telescope at Green Bank, WV, initiating Project Ozma, which has since morphed into SETI. For a few years around 2003 I ran the Seti@home "screen saver" application (actually, I soon turned off the screen saver part because it runs three times faster without it).

It has been estimated that the combined computer power of perhaps a million people running this application is about a petaflop (10¹⁵ calculations per second). That was several years ago, and it would not surprise me if the current figure is closer to an exaflop (10¹⁸/s). I do not run it at present because I don't run my computer when I'm not there. That may change now that I have a computer that is a bunch faster than the one I had in 2003, and a better Internet connection.

The fiftieth anniversary of Project Ozma is also the occasion for Paul Davies, who chairs the SETI Post-Detection Taskgroup, to issue his book The Eerie Silence: Renewing Our Search for Alien Intelligence. The book could be taken as a long riff on the question Enrico Fermi asked in about 1946: "Where is everybody?" It might seem that the prevalence of UFO reports beginning the following year provides an answer, but so far, these stories tell us lots about human nature, and nothing about space aliens. Dr. Davies takes this up as he closes his first chapter, "Is anybody out there?"

Perhaps you know of Dr. Drake because of the Drake Equation:

N_c = N* f_p N_e f_l f_i f_c L_c

These are, in order, the Number of (possibly) Communicating civilizations, a product of the Number of Stars formed yearly, the fraction thereof with planetary systems, the number of planets per system that are potentially habitable, the fraction thereof that develop life, the fraction of planets with life that develop intelligence (of a type and level that can build radio telescopes and powerful transmitters), and their average Lifetime as interstellar communicators.

Only the first and last component of N_c can be fairly estimated from data at hand. N* in our Galaxy is about seven per year at present, though it was a little higher a few billion years ago. L_c for Earth is less than 100 years for our accidental emissions of broadcasts such as old Amos 'n' Andy or I Love Lucy until the end of high-powered analog TV broadcasting just last year. But most of us have been getting our TV from cable for a decade or more already (ours is the last house on the block to use antenna reception for all the TV we watch). I use TV as the standard because VHF and UHF signals get out of the atmosphere much more readily than AM radio, and have quite a bit more power than FM radio, which is also VHF. Yet if we decide to become "radio loud" so as to attract attention, then L_c for Earth might be as long as we last without blowing ourselves up. Whether that is another generation or many millennia, who knows? But the Sun will remove civilization in about half a billion years, so that's our extreme limit.

As the author describes, the opinions about the other factors range the map, but are clustered about pessimistic and optimistic, with little to go on for a middle ground. By the Copernican principle—we're pretty average, not special in any way—we might conclude that life abounds in the cosmos, and most stars with habitable planets have smart "people" living there. Using some fairly optimistic numbers in the Drake Equation yields an estimate of about 20 million planets out there, all trying to communicate with their nearest neighbors. However, that puts the average spacing between communicating planets at about 50 light years.

Then there is the opposite view, the "rare earth" analysis, based on the notion that for life to form might be harder than we think, and for intelligent life (that can build big radio dishes) to evolve might be even harder. Using one-in-a-million for a couple of the parameters in the Equation indicates that the chance for even one Earth to arise (that would be us), is a one-in-a-billion or -trillion shot, so that we are a lucky fluke. Which is it? We won't know, and can't know until we either hear from someone or find other evidence that someone is out there.

Could we receive old TV shows from our planet if we put one of our radio telescopes on a planet around the star Sirius? Not yet, except perhaps with the Arecibo radio telescope, which is half a kilometer in diameter, but can't be steered (it is anchored to a bowl-shaped valley in Puerto Rico). How about with this array:

Maybe, maybe not. The Allen Radio Telescope Array at the Hat Creek Radio Observatory is online now. While each dish is relatively small, there are, so far, 42 of them. This array is sufficient to detect a signal of the type we could produce using Arecibo and a kilowatt transmitter, pointed right at a star of interest. If smart aliens are sending a pulsed signal, say with a peak power of a megawatt, 0.1 second on, 99.9 seconds off for an average power of a kilowatt, we'd hear it from as far away as a hundred light years or so.

What does it mean that, after fifty years of listening, we've heard nothing we can clearly say, "This is them!"? Firstly, we've only listened in the direction of about 0.01% of the stars within 100 light years. There are lots of stars out there! Secondly, we've only listened in a small part of the potential radio (and light) spectrum. There are lots more wavelengths out there!!

From the ground, the Allen array looks big, but this aerial photo (from Google Earth) shows that there is not much "capture area". The Allen dishes are the white blobs that are casting shadows. The larger things are part of the older radio observatory. Spreading them out over a large field makes it possible to focus sharply on stars of interest, but doesn't strengthen the signal. The whole array has less capture area than Arecibo, but has the virtue of being steerable.

Is there something besides radio signals that would indicate intelligent life? We are not yet capable of getting the spectrum of an exoplanet's atmosphere, so we can't even detect an oxygen/water atmosphere or photosynthesis, both of which would at least tell us "life happened". Could we detect human activity on Earth, even from a nearby place like Neptune? Dr. Davies has a chapter on such questions. In fact, he is very thorough in his analysis of all the factors that could tell us of life unlike our own. For example, we might someday find creatures on Earth (probably bacteria) with a different code for turning DNA into proteins.

I mean really different. There are at least seventeen variations on the "standard" code used by all Eukaryotes, found among Bacteria and Archaea. But they are all very similar and probably indicate branches off the "standard" tree, rather than separate life-initiation events. So we're talking a completely different code, and perhaps a basis in four rather than three DNA bases per codon, or a set of quite different amino acids, other than the twenty or so in use by all (so far) known life. Such a finding would help us say that life wasn't so hard to get started, because it did so more than once on Earth…or, alternatively, that it also started somewhere nearby such as Mars and came here on a meteorite (or spacecraft?) and flourished once it got here.

The author proposes widening the SETI search. He really tries to think outside the box. The way we are searching now is based on what we might do if we were trying to send a signal for others to receive. What if, instead, we look for signals that accidentally come our way, from one planet to another who are already in contact? Could we eavesdrop? We'd have to be close to a direct line between them, or the beam being used would miss us. The narrowest beams would be not radio signals, but IR or visible laser beams. It is a tossup whether light is better, though, because stars are bright in the visible and near-IR spectra, compared to radio.

Then there are artifacts. Will we one day find a black obelisk on the moon? How might it signal its presence, if it wants to be found, but is waiting for us to become spacefaring, à la the film 2001: A Space Odyssey? We've already blown that chance until at least 2030. But there are lots of possibilities and the book outlines everything I might have thought of, and more.

The last question for the last chapters is, should we ever receive a definite interstellar signal, at Allen array or elsewhere, then what? Do we crank up a transmitter and shout "Hello!"? Is that smart? How will it affect our culture and politics, and particularly, our religions? The various major religions of Earth have survived the Copernican revolution, and are currently working through the Darwinian revolution. What would an Alien revolution be like? Would it be the end of our civilization, or the trigger for a better one? Probably neither, at least not in the short term. People get over things. Since Giordano Bruno was burned at the stake for espousing that other planets had people, even religion has gotten over it, to some extent, and most religious leaders make sounds like they could accept aliens as just another kind of people who need faith.

What'll we do if the first interstellar communication we receive is evangelistic in nature? The author doesn't ask this, but it naturally follows from understanding that it is quite like one of our wealthier religious leaders to build a dish and buy a big transmitter and send an evangelistic message outward. How much would they really be like us?

Lots of questions simply have no answer yet. The book ends by saying that we simply don't know.