The Large Spaceship Competition


We space opera fans like big things:  sweeping plots and intrigues, larger-than-life characters, huge explosions.  And big spaceships.  The bigger, the better.

You remember the opening of the original Star Wars.  At the top of the frame, the Imperial Star Destroyer looms into view.  And keeps coming, for what seems like forever.  With this visual cue, Lucas communicates immediately the sheer scale of his story.

In a long story, this can lead to a Lensman Arms Race in terms of spaceship size—each new construct eclipsing the last.  One might wonder:  How far can we go with this?  Who holds the record for Largest Spaceship of All?

Traditional spacecraft

Saturn V-Apollo on transporterOrdinary, garden-variety depictions of spaceships are long since out of the running—not just real vehicles like the Saturn V-Apollo, but fictional ones that are meant to be big.  Kate Wilhelm’s title “The Mile-Long Spaceship” (1957) doesn’t sound even slightly impressive any more.  According to Wikipedia, those Star Destroyers range up to 2,915 meters, almost two miles.  The famous size comparison chart by Dirk Loechel displays these, along with the Independence Day mothership, the Dune Spacing Guild Heighliner, the Borg cube, and many more—but Loechel set his cutoff for the image, arbitrarily, at 24,000 meters:  “I had to draw the line somewhere.”

That’s just getting started.

“That’s no moon”

The alien probe in Clarke’s Rendezvous with Rama, which I’ve mentioned a couple of times before, is 50 kilometers long and 16 wide (31 by 10 miles).  That’s bigger than a lot of Earthly cities.

Death StarStar Wars’ Death Star, famously misidentified as a moon, has been estimated at between 100 and 160 kilometers in diameter (62 to 100 miles), at least three times larger.  The second Death Star, from Return of the Jedi, spanned somewhere between 200 and 400 kilometers (up to 250 miles), according to the same Wikipedia article.

Skylark of Valeron coverFor a long time I idolized E.E. Smith’s Skylark of Valeron as the epitome of spaceship scale.  The ship (not the novel of the same name), “almost of planetary dimensions,” is a sphere one thousand kilometers in diameter—about 621 miles (ch. 20).  That’s over twice the size of the large economy-size Death Star.  (A blogger going under the title Omnivorenz has done a detailed analysis of the various Skylark series spaceships.)

However, we’re still in the moon category, not yet up to planet-sized.  (Of course, if astronomers keep changing the rules on what counts as a planet, the two size ranges can overlap.)

Planets in motion

At this stage, we need to think about what counts as a “spaceship.”  Surely one requirement is that it be able to move in a directed fashion—otherwise the International Space Station would count.  But does it have to be a construct, a made thing?  Or can you take an existing mass and equip it with motive power?

Quite a few science fiction writers have depicted mobile planets (not simply in the sense of moving in an orbit, but of guided, directed motion).  In Blish’s Cities in Flight series, the characters twice use spindizzy drives to send whole worlds careening through the heavens.  E.E. Smith’s Lensmen, after a point, deploy “dirigible” planets almost routinely—not to mention antimatter objects (“negaspheres”) of comparable mass.  In The Wanderer, Fritz Leiber has not one, but two, traveling planets approach the Earth.  (The original source of the word “planet” is a Greek word meaning “wanderer.”)

There’s a series of stories by Robert Reed about something called “the Greatship,” but I haven’t managed to read them yet.  The blurbs describe the Greatship as “larger than worlds” and “apparently built from a re-engineered gas giant” – which would put us into a distinctly different size class from even an Earth-type planet.

And beyond

Here’s a question:  Does a “spaceship” have to be a single contiguous object?  Or can it be an array of objects that travel together, but are not physically connected?

In Larry Niven’s Known Space universe, the species known as Puppeteers flees a coming galactic disaster, not by leaving their homeworld, but by taking their planet with them—along with four others, arranged in a “Klemperer rosette” around their common center of gravity.  That’s traveling in style!  This “Fleet of Worlds” moves slower than light, but not much—and it’s five times larger, altogether, than a Blish or Smith flying planet.

The Cometeers coverBut Niven was writing hard science fiction, with some attempt at scientific plausibility.  The great space operas of earlier eras weren’t constrained by such trivial considerations.  For a long time, my list of giant spacecraft was topped by the so-called “comet” piloted by the adversaries in Jack Williamson’s 1936 classic The Cometeers.  It’s not a comet at all, but a green force-field shell enclosing an entire system of worlds:  the heroes count 143 planets, plus an artificial sun (ch. 13).  The eponymous alien Cometeers sail this congeries of worlds about the universe like space pirates on a grand scale.  It’s the biggest guided space-traveling object I’m run across that’s described with any precision.

The real prize, however, belongs to Arthur C. Clarke.  In the unthinkably far future of The City and the Stars (1956), a reconstruction of history shows the leading intelligences of a galactic civilization leaving the Milky Way on a voyage of exploration in what is apparently an entire star cluster, set into motion by energies on a galactic scale:

They had assembled a fleet before which imagination quailed.  Its flagships were suns, its smallest vessels, planets.  An entire globular cluster, with all its solar systems and all their teeming worlds, was about to be launched across infinity.

The long line of fire smashed through the heart of the Universe [i.e., the Galaxy], leaping from star to star.  In a moment of time a thousand suns had died, feeding their energies to the monstrous shape that had torn along the axis of the Galaxy, and was now receding into the abyss. . . .  (ch. 24)

That’s about as far as my imagination will go, to be sure.

The pursuit of wonder

TV Tropes collects a number of these references, and more, under the heading Planet Spaceship.

As we contemplate these logarithmic jumps in scale, we may note that after a point, the whole exercise can become meaningless.  If your “ship” includes whole planets and solar systems, why go anywhere?  It’s rather mysterious why Williamson’s Cometeers would need to roam the universe preying on other star systems (other than to provide a challenge for our dauntless heroes).  What are they getting that they haven’t already got ‘on board’?

The one likely answer may be, to see what’s out there (assuming you need this large a vessel to take you).  This is the primary reason Clarke’s far-future intelligences set out on their journey:

All we know is that the Empire made contact with—something—very strange and very great, far away around the curve of the Cosmos, at the other extremity of space itself.  What it was we can only guess, but its call must have been of immense urgency, and immense promise.  (ch. 24)

In a way, the exploration motive—“new life and new civilizations”—brings us back to where we started this exercise in scope.  Simply contemplating larger and larger objects brings us some degree of awe—a touch of that “sense of wonder” for which science fiction and fantasy are famous.  But a much greater wonder springs from the idea of meeting wholly new experiences—“very strange and very great.”

The grandest justification for leaving our world may be sheer discovery—even if we end up, like the Puppeteers, taking our world with us when we go.

The Good King

I began to wonder some years back about the curious preference for monarchy in futuristic settings.  In the world at large, monarchies have been retreating in favor of republics and democracies, at least in theory, since 1776.  Why are SF writers so fond of equipping future societies with kings, emperors, and aristocracies?

Star Kingdoms

We can pass lightly over the old-time, pulp-type stories where royal rule is merely part of the local color:  Burroughs’ A Princess of Mars (1912), Edmond Hamilton’s The Star Kings (1949), E.E. Smith’s The Skylark of Space (1928) with its Osnomian royal families.  Here, like flashing swords and exotic costumes, monarchy is simply part of a deliberately anachronistic setting.  Similarly in high fantasy, where aristocracy comes naturally in the typical pseudo-medieval milieu.

But we see royal or aristocratic governments in more modern stories too.  Asimov’s Foundation stories are centered around a Galactic Empire.  (Since that series was based on Gibbons’ The History of the Decline and Fall of the Roman Empire, an Empire was inevitable.)  Similarly in Star Wars, which draws heavily on Asimov.  Jerry Pournelle’s CoDominium future history has a First and a Second “Empire of Man.”  David Weber’s heroine Honor Harrington serves the “Star Kingdom of Manticore” (later “Star Empire”), modeled closely on England around 1810.  Lois McMaster Bujold’s Vorkosigan Saga contains a number of polities with different forms of government, but many of the stories focus on Barrayar, which has an Emperor.  Anne McCaffrey’s popular Pern series has no monarch, but has two parallel aristocracies (the feudal Holders and the meritocratic dragonriders).  It got to the point where I began to feel a decided preference for avoiding monarchical or imperial governments in SF storytelling.

The Lure of Kingship

Aragorn with crownThere’s something that attracts us in royalty—or we wouldn’t see so much of it.  I encountered this puzzlement directly.  As a kid reading The Lord of the Rings, I was as moved as anyone by the return of the true King.  I asked myself why.  If I don’t even approve of kingship in theory, why am I cheering for Aragorn?

The reasons we’re drawn to monarchy seem to include—

  • Kings are colorful. (So are princesses.)
  • Stability
  • Personal loyalty
  • Individual agency

The first point is obvious, but the others are worth examining.


It’s been pointed out that even in a constitutional government, a monarch provides a symbolic continuity that may help to hold a nation together.  British prime ministers may come and go, but Queen Elizabeth is always there.  (Literally, at least within my lifetime.)  This gives some plausibility to the idea of a future society’s returning to monarchy.

Something like this stabilizing function is behind commoner Kevin Renner’s half-embarrassed harangue to Captain Rod Blaine, future Marquis of Crucis, in Niven & Pournelle’s The Mote in God’s Eye:  “maybe back home we’re not so thick on Imperialism as you are in the Capital, but part of that’s because we trust you aristocrats to run the show.  We do our part, and we expect you characters with all the privileges to do yours!”  (ch. 40)

Unfortunately, relying on the noblesse oblige of the aristocrats doesn’t always work out well.  It depends on who they are.  For every Imperial Britain, there’s a North Korea.  When the hereditary succession breaks down, you get a War of the Roses or Game of Thrones.

Too much depends on getting the right monarch.  By the law of averages, it doesn’t take long before you get a bad ruler, whether by inheritance or by “right of conquest”—and you’re up the well-known creek.

Personal Loyalty

Personal loyalty appeals to us more strongly than loyalty to an institution.  One can pledge allegiance to a state—but even the American Pledge of Allegiance starts with a symbol:  the flag, and then “the Republic for which it stands.”  Loyalty to an individual moves us more easily.

This kind of loyalty doesn’t have to be to a monarch.  Niven & Pournelle’s Oath of Fealty explores how loyalty among, and to, a trusted group of managers can form a stronger bond than the mere institutional connections of a typical modern bureaucracy.  One can be faithful to family (the root of the hereditary element in kingship), to friends, or even an institution or a people.  But it’s easiest with an individual.  This loyalty is the basis for the stability factor above.

Individual Agency

The vast machinery of modern government sometimes seems to operate entirely in the abstract, without real people involved.  “Washington said today . . .”

In fact it’s always people who are acting.  But it’s easier to visualize this when you have a single person to focus on.  “When Grant advanced toward Richmond . . .”  In the extreme case, we have the ruler who claims to embody the state in his own person:  “L’état, c’est moi” (attributed to Louis XIV, the “Sun King” of France).

In a fascinating 2008 essay, Jo Walton quotes Bujold on political themes in SF:  “In fact, if romances are fantasies of love, and mysteries are fantasies of justice, I would now describe much SF as fantasies of political agency.”  A science fiction character is frequently involved in effecting a revolution, facing down a potential dictator, or establishing a new order—exercising autonomous power.  Walton links this notion of political agency to the fact that SF illustrates change:  “SF is the literature of changing the world.”  The world-changers can be outsiders, or they can be the rulers themselves—as in a number of the examples above.

It’s not surprising that we’re attracted to characters who act outside the normal rules.  We (especially Americans, perhaps) are fond of the idea that good people can act in ways that are untrammeled by the usual conventions.  I’ve already mentioned Robin Hood.  And the whole concept of the superhero—the uniquely powerful vigilante who can be relied on to act for the good—is powered by this attraction.

But this idealization of individual initiative is also dangerous.  Too much depends on getting the right hero—or the right monarch.  It can only work if the independent agent is seriously and reliably good:  virtuous, in the classical sense of virtue as a well-directed “habit” or fixed character trait.  Even then, we may be reluctant to give any hero unlimited power.  Too much is at stake if it goes wrong.

The Rule of Law

Our admiration for the powerful ruler is always in tension with our dedication to the rule of law:  “a government of laws, not of men,” in the well-known phrase attributed to John Adams.  We can see this as far back as Aristotle:  “law should rule rather than any single one of the citizens.  And following this same line of reasoning . . . even if it is better that certain persons rule, these persons should be appointed as guardians of the laws and as their servants.”  (Politics book III, ch. 16, 1287a)

No human being can be trusted with absolute authority.  This is the kernel of truth in the aphorism that “power tends to corrupt and absolute power corrupts absolutely.”  But we can’t get along without entrusting some power to someone.  When we do, it had better be someone who’s as trustworthy as possible.

The Ideal of the Good King

Thus the true king must be a virtuous person—a person of real excellence.  This is the ideal of an Aragorn or a King Arthur, whose return we’re moved to applaud (even against our better judgment).  (It should be obvious that the same principles apply to the good queen—or emperor, empress, princess, prince:  the leader we follow.  But I’ll continue using “king” for simplicity’s sake.)

What virtues do we look for in a good monarch—aside from the obvious ones of justice, wisdom, courage, self-control?

If the ruler or rulers are going to be “servants of the laws,” they require humility.  A king who serves the law can’t claim to be its master.  Arrogance and hubris are fatal flaws in a ruler.  For example, we should always beware of the leader who claims he can do everything himself and is unable to work with others.

The good king is also selfless—seeking the common good of the people, not his own.  Self-aggrandizement is another fatal flaw.

In effect, what we’re looking for is a ruler who doesn’t want to rule:  a king who believes in the sovereignty and the excellence of common people.

Aragorn defers to FrodoIt’s significant that Aragorn, our model of the good king, is introduced in LotR as “Strider,” a scruffy stranger smoking in a corner of a common inn.  Even when he’s crowned in victory, he remembers to exalt the humble.  The movie has him tell the four hobbits, “You kneel to no one.”  Tolkien’s text is more ceremonious:  “And then to Sam’s surprise and utter confusion he bowed his knee before them; and taking them by the hand . . . he led them to the throne, and setting them upon it, he turned . . . and spoke, so that his voice rang over all the host, crying:  ‘Praise them with great praise!’”  (Book VI, ch. 4, p. 232)

We see the same essential humility and selflessness in other admirable leaders, kings or not:  Taran in the Chronicles of Prydain, and the revolutionary princess in Lloyd Alexander’s Westmark trilogy; Niven & Pournelle’s Rod Blaine; Jack Ryan in Tom Clancy’s novels; “Dev” Logan, head of Omnitopia Inc. in Diane Duane’s Omnitopia Dawn—the unpretentious opposite of the “imperial CEO.”  America was fortunate enough to have such an example in the pivotal position of first President, George Washington.

The Alternative

At the other end of the spectrum, the most dangerous person to trust is an unprincipled and unscrupulous autocrat—someone convinced of his personal superiority and infallibility.  Giving power to an individual who has no interest in serving the common good, but only in self-aggrandizement, puts a nation in subjection to a Putin, a Mussolini, a Kim Jong-un.

The antithesis of the good king is the tyrant, who, however innocently he may start out, figures in our stories mainly as the oppressor to be overthrown.  It’s much better, if possible, to intercept such a potentially ruinous ruler before the tyranny comes into effect:  Senator Palpatine before he becomes Emperor, Nehemiah Scudder before he wins his first election.  Allowing the tyrant to gain power may make for good stories, but it generates very bad politics.

If we must have strong leaders, then in real life as well as in stories, character is key—and hubris is deadly.

Changing History: “Timeless”

The initial episode of NBC’s new time travel series, Timeless (premiered Oct. 3, 2016), does a neat job of handling the classic trope of changing the past.  There’s more to that kind of plot than generally meets the eye.

Spoiler Alert!The following necessarily contains spoilers for the first Timeless episode, so if you haven’t seen it and want to, be careful when scrolling down.  I’ll drop another alert message at the point where the spoilers begin.Poster for Timeless

The Lure of the Past

Oddly enough, travel to the past fascinates us more than travel to the future.  One might expect it to be the other way around.  After all, we’ve been to the past.  The first classic time travel tale, H.G. Wells’ The Time Machine, concerned itself exclusively with the future.  But it’s backwards time travel that lets us imagine changing the present by altering its causes—and produces the causal tangles that are unique to time travel stories.

Larry Niven’s essay “The Theory and Practice of Time Travel” (found in All the Myriad Ways) points this out:  “When a child prays, ‘Please, God, make it didn’t happen,’ he is inventing time travel in its essence. . . . The prime purpose of time travel is to change the past; and the prime danger is that the Traveler might change the past.”

The Past Doesn’t Change

Some stories assume that the past can’t be changed.  The time stream protects, or heals, itself automatically once the moving present has passed.  There was an old-time SF story (anyone remember the title?) in which successive attempts to change history misfire because of progressively more unlikely accidents.  The gun misfires.  The bullet misses.  A bystander intercepts the bullet.  A meteor knocks the gun out of the assassin’s hand.  The hypothesis has an air of fate about it, as in the Greek myths.

But unchangeability needn’t be a matter of fate.  It may simply reflect the fact that the past event has already happened, incorporating any interventions from the future that may have taken place.  There is a single past event, which is the product of all its causes, whether they come from the event’s past or its future.  As TV Tropes puts it, “You Already Changed the Past.”  Robert A. Heinlein wrote some of the most famous time travel stories using this approach to generate “constructive” or “ontological” paradoxes—By His Bootstraps and “—All You Zombies—”.

A technology that only allows viewing the past, rather than interacting with it, falls into a similar category.  There’s no chance of changing things; we’re mere observers.  Isaac Asimov’s The Dead Past leaps to mind.

These kinds of stories are fun, but they don’t have quite the emotional appeal of “Make it didn’t happen.”

How A Change Propagates

Suppose, then, that we can change the past.  How exactly is that supposed to work?

A writer sometimes introduces a sense of urgency into the plot by imagining that a change in history propagates through reality in a process that itself takes time (of some sort).  This is what creates the tension in Back to the Future.  We can see Marty’s family gradually disappearing as his disruption of history works its way forward.  Presumably Marty disappears last because he was conceived last.  If he doesn’t reestablish history before he disappears, it’s all over.

This makes a weird sort of sense, because natural processes do normally propagate gradually.  Even gravity has its waves.  But it does result in the curious phenomenon of a reality that isn’t entirely self-consistent.  Marty’s parents never got married, but Marty himself is still inexplicably there.  (For the moment.)

It makes more sense, maybe, to picture the change as taking effect instantaneously.  Take away the causal “supports” for something, and it’s no longer there at all.  This assumption would have made Back to the Future a much shorter movie—and highlighted the “Grandfather Paradox” at the core of its plot.  The time lag gives Marty a chance to cure the paradox before it fully takes effect.

What Happens to the Traveler?

But we’re assuming that the causal ripple from history’s change follows the time traveler even when the traveler’s world line has looped around into the past.  What if that isn’t how it works?  (We’re inventing a theory of time travel; we can make what assumptions we wish.)  If the traveler is absent from the future when the change “gets there,” will the traveler be affected at all?

If the traveler is affected by the same change that affects everything else, we get a time stream that’s more consistent, but harder to tell a story about—because no one in the story will remember the change.  The traveler’s memory alters along with everything else.  (There’s an old SF story about this, too—and it only works because the reader is outside the story’s time stream.  At the end the bizarre monster that was human on page one proclaims, ‘the time experiment is over, and nothing has changed.’  The story only works from an omniscient point of view.)

So a time travel story almost always assumes that the traveler, who was out of the affected time region when the change occurred, remembers the old when she encounters the new.

Here Be Spoilers!

You Can’t Go Home Again

Here’s where Timeless comes in.  Villains of some sort—or are they?—steal the secretly developed time machine and set off to change history.  Our three heroes take the older prototype vehicle (a little less streamlined than a DeLorean) and follow.  They don’t quite succeed in preventing their adversaries from altering the past.  The Hindenburg explodes on its return trip, rather than on its arrival in America.Hindenburg disaster

When our heroes come back to the present, their colleagues believe the zeppelin had always exploded on its return trip—because the change in history has affected them.  The three travelers have to explain to them what’s changed.  In a sense, they no longer belong in the world from which they set out.  It’s an unusual and interesting situation for a TV series.

The Butterfly Effect

So far, we haven’t seen what larger alterations or political ramifications may have resulted, in this new world, from the deaths of several prominent figures on what was now the Hindenburg’s ill-fated second flight.  But the personal implications turn out to be devastating.

Butterfly effect graphicThe screenwriters also have a good handle on another time travel staple, the “butterfly effect,” named for the metaphor that in a massive chaotic system, a butterfly flapping its wings on one continent might result in a tornado in another (or, possibly, named for a classic Ray Bradbury short story).  When main character Lucy Preston comes home from her adventure in the past, she is overjoyed to find that her mother, comatose when Lucy left, is now perfectly healthy.  But Lucy is appalled to find that her beloved sister never existed.  How could the Hindenburg’s altered history have anything to do with this, she cries—and now she has new, and very mixed, motivations as to setting time back on its original course.

The show thus picks up on a theme that’s frequently neglected in a tale about changing the past.  Each change has unpredictable ramifications.  Marty McFly comes home to find his parents much improved, his siblings successful, and the despised Biff reduced to a cipher.  But what of all the people in town who will have interacted with the changed McFlys and Tannens over the past thirty years?  If even minor events can have large long-range effects, it may not be so easy to confine a temporal change to the intended consequences.

This means that our Timeless heroes may have no way to put things back the way they were.  The change may be essentially irreversible—a sort of temporal entropy.  Anything they do to counteract the bad effects of the original change will lead to still more alterations.  They really can’t go home again.

If the writers carry through this fascinating, if rather chilling, line of thought in subsequent episodes, we may get some really interesting story lines—as time goes on.

How to Stage an Alien Invasion

We love our alien invasions.  Since The War of the Worlds (1897), poor Earth has suffered a steady stream of hostile arrivals—frequently from Mars, but recently from farther afield, as the possibility of other intelligent life in our solar system wanes.

We have one coming up this month, with the June 24 movie premiere of Independence Day:  Resurgence, a sequel to one of the more successful invasions of the last twenty years.  It seems like a good time to look closely at our opponents.

Footfall, a 1985 novel by Larry Niven & Jerry Pournelle (still available in print), is not only a great yarn, but a textbook model of how to write a modern invasion story.  We can look at it as a test case, like an existence proof in mathematics:  What kinds of conditions have to be fulfilled for a believable alien invasion, given what we now know about other planets?


Let’s define the target.  We’re talking about the good old classic invasion story, where the bad guys show up in person, make a direct assault, and we beat them.  That isn’t the only possibility.  There are other variants, such as infiltration, or scenarios where the Earthlings lose and end up a subject species.  But let’s look at what premises make a triumphant Independence Day-style plot viable.


It was easy for Wells.  His relatively nearby Martians could fire off a series of cannon shells, more or less, to land on Earth, break out their tripods, and mount their campaign.  Wells’ tour de force ending, of course, has the Martians beaten not by human opposition, but by humble bacteria.  (Arguably the best moment in the original Independence Day is when Jeff Goldblum realizes we can best the enemy by using a contemporary analogue of the Wellsian microbes—a computer virus.)

But modern invaders have to come from a greater distance.  Regrettably, none of the plausible abodes of life in the solar system have panned out.  Gone are old-time SF’s sweltering jungles of Venus, the canal-crossed deserts of John Carter’s Mars.  Until we’re ready for an attack by potential microbes from Europa, or hypothetical floating denizens of Jupiter’s atmosphere—neither of which, if they exist, have shown any signs of capability for interplanetary excursions—we have to look to interstellar sparring partners for a really good invasion.

This intensifies a long-standing problem with invasion stories.  If they got here, and across the interstellar gulfs at that, their technology must be literally light-years ahead of ours.  How can we expect to beat critters with such vastly advanced technology?  The balance of power is inherently skewed against us.

Paired with this is the question of motivation.  Why are they here?  What do the invaders want that would drive them to come all the way to Earth for it?

This is the easiest place for invasion stories that aren’t built on sound science to go astray.  We need only mention the 1983 TV mini-series “V,” which, though it had many admirable aspects, fell sadly short on the science side.  V gives not one, but two, implausible motives for the seemingly-benevolent Visitors.  They’re here to steal Earth’s water—as if there weren’t vast amounts of ice scattered around our solar system, and probably most other systems, for the taking.  And they’re here to eat us; apparently not only are humans compatible with a completely alien biology, but we’re a tastier treat than more edible and obtainable animals.  Sensible extraterrestrials need a better reason to traipse across the light-years than a local hamburger shortage.


Niven & Pournelle’s epic adventure handles both these questions so beautifully that it might have been plotted specifically to answer them.

Our not-quite-friendly visitors, the fithp (the singular is fi’), arrive in a large interstellar vessel, which launches smaller ships to conduct the attack.  Why are they here?  They’re looking for Lebensraum — living space.  The fithp have been exiled from their homeworld as the result of a conflict among factions—like the Protectors in Niven’s novel Protector.  They need a new place to live.  Among other things, this means “defeat is not an option”:  they can’t go back.  That ups the stakes.

But this exile premise also solves some of the balance-of-power problems.  The fithp’s resources are strictly limited.  There won’t be any reinforcements.  They can’t bring anything more from their homeworld.  All we have to do is defeat this batch of opponents, and we win.

Niven & Pournelle strengthen this limitation on the aliens, and incidentally increase scientific plausibility, by making their mother ship Message Bearer a slower-than-light vessel — a Bussard ramjet.  Their journey takes decades.  This distances the fithp even further from any potential homeworld support.  The authors also use it to introduce another twist:  there’s dissension between the space-born fithp, on one hand, and those who lived on their homeworld and are now awakened from suspended animation, on the other.  This division becomes important as the plot develops.

Without having to account for faster-than-light travel, Niven & Pournelle can give the fithp technology that isn’t too far ahead of our own.  Human numbers—and political, psychological, social characteristics—can make up for the technological imbalance.

In addition, the fithp don’t fully understand their own technology.  They’ve learned a lot of it from records left by their Predecessors, rather than developing the science themselves. This makes them less able to innovate.  By contrast, the humans’ response is a masterpiece of improvisation.  We make the best of what we have.  This, too, helps even the scales.  (Lesson for humans:  Continue fostering that STEM education.)


In the course of this worldbuilding, Niven & Pournelle give us fully fleshed-out aliens, with a coherent culture and society, understandable but different from our own — not an easy task.  Among other things, the fithp are sympathetic characters.  They are people, not just faceless attackers.  We see events from their viewpoints as well as our own.  This makes the story not only more believable, but more interesting.


The original Independence Day scores modestly on these two plausibility counts.  Motivation:  The aliens travel the stars like locusts, stripping planets of their resources.  No details are given, but the basic idea is not unreasonable, particularly in light of contemporary environmental concerns.  Balance of power:  We’re hopelessly behind in technology—but the aliens’ laziness (using our own satellites for signaling), Goldblum’s bright idea, and a captured alien ship get us (barely) over the hump of the willing suspension of disbelief.

We’ll see shortly how these premises play out in the Independence Day sequel—applying the Niven & Pournelle standard.