CALLISTO'S PELLUCIDAR

There is, of course, not even a hint that Callisto is a hollow world.    So at this point, we’ve leaped into freefall without a net.

But, on the other hand, Lin Carter did follow Burroughs Pellucidar in forging his own underground world, Zanthodon.   For the record, Zanthodon is an immense pocket approximately a hundred miles below the north African sands, about the size of a small continent or large island, inhabited by everything from Dinosaurs and Mammoths, to Cavemen, Minoans and Barbary Pirates.   Zanthodon isn’t quite Pellucidar, the dimensions and directions don’t match, but in the Burroughs Universe, a place like Zanthodon may be an outlier, a partially stabilized Hoos or gateway.

And the thing is, that if Callisto really is in the Burroughs universe with Barsoom, as we speculate, then its quite likely that it may be a hollow world.   After all, the Burroughs Universe contains two hollow worlds in Earth/Pellucidar and The Moon/Va-Nah.   One could be a fluke.  Two hollow worlds back to back suggests that this may be a common formation.   Elsewhere, I’ve speculated about the possible nature of Barsoomian and Amtorian Pellucidars.   So, allow me to do the same thing here....

Assuming that there is such a thing, what would Thanator’s Pellucidar be like?  For starters, let’s call it Vanadar, as a tribute to Va-Nah and Pellicidar.

Well, first, we can calculate its dimensions.  Gravity for the Moon/Vah-Nah, Earth/Pellucidar systems is the same on both sides.  When you are standing on Pellucidar, you don’t fall in towards the center, any more than you fall out into space, standing on the outside.  This means that gravity is exerted from the shell itself in both directions, inwards and outwards.

Now assuming that the composition of the shells is uniform from one world to the next (which is a pretty big assumption, but we don’t have much to go on), then the variation in gravity from one world to the next comes from the different thickness of the shells.    The Moon’s shell is 250 miles thick, producing 16% gravity.  Earth’s shell is 500 to 800 miles thick, producing terrestrial gravity.

Thanators gravity is about 80% that of Earth’s, so proportionately, its shell should be much thicker than the Moons, much closer to Earth’s.   Anywhere from 450 to 750 miles?   We have to assume that Thanator’s shell is much, much thicker than the Moon’s, so despite Thanator being almost half again as large as the Moon, the internal sphere may actually be smaller.   The shell is probably close to the thickness of Earth’s, definitely much greater than Earth’s proportionately.   Since it is a smaller world than Earth, the shell may actually be thicker in real terms to make up for it.

Now, taking the diameter of Thanator, roughly 2770 miles, and subtracting the thickness of the shell (on both sides) means that the inner sphere of Vanadar is, very roughly, somewhere between 1870 miles and 1270 miles.   Both of these would be very rough guesses.   Now with internal diameters of between 1270 miles and 1870 miles, we can then calculate the surface area of the inner Vanadar, somewhere between five million and ten million square miles.   This is compared to a surface area on the topside of about twenty five million square miles.

In comparison, the internal surface areas of Pellucidar is about a hundred and fifty million square miles, to two hundred on the surface.  The internal surface area of Vah Nah is eight million, compared to sixteen million on the surface.   The ratios in these cases being relatively close, 3 to 4, and 1 to 2.  Vanadar may be as extreme as 1 to 5.

Thanator has the most lopsided ratio of surface to interior, because of its thick shell.  And if we assume that the shell is towards the thicker side, it has one of the smallest inner worlds we’ve yet seen, perhaps as little as five million square miles, or midway between Australia and South America,  no larger than the Antarctic continent.

One consequence of this is that your inner world will have the most pronounced curvature so far.  If Pellucidar makes one feel as if you are sitting in a great bowl, then inner Thanator may make you feel as if you are at the bottom of a shot glass.

There are other consequences.  With curvature that extreme, there’s literally nowhere for rock to fold except straight up.   Generally, folding on the inside of a curve should produce higher extremes than on the outside.  All things being equal, Pellucidar’s mountains should be taller than Earth’s (although if Pellucidar is composed of smaller and faster moving plates, its mountains would be shorter and shorter lived).   Vah-Nah’s geography in the Moon Maid should be more extreme than the outside, and if you read the Burroughs novel, there are suggestions that this is true.   If this is the case, then Vanadar likely is potentially a land of savagely steep mountains, cliffs and chasms.

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What else can we determine?

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We know that Earth has permanent Polar openings to Pellucidar, and it appears that from time to time, other portals appear and disappear in Earth’s surface offering entry to Pellucidar, leaving remnants or outposts like Pal-Ul-Don, Caprona, Maple White Land and Skull Island.  This is apparently a slow but ongoing process on Earth, and is a factor of Earth’s live geography.  Essentially, slow ‘whirlpools’ form in the geological flows between inner and outer worlds.

On the Moon, which was smaller and colder, geological death came faster.  The ‘whirlpools’ froze in place, leaving open holes, or Hoos, on the satellite.

Vanadar is likely unique.  Like the Moon and Earth, it was probably geologically active, with slow ‘whirlpools’ forming polar openings and other holes.  However, the greater thickness of its crust and its extreme curvature suggests that it remained geologically live much longer than the moon.  Perhaps it is still geologically live.   However, the greater thickness from the moon, and greater curvature from Earth probably made it much harder for Hoos or holes to form.   Indeed, Hoos might not form at all, and there may be no communication between inner and outer worlds.

On the other hand, if they did form, its likely that the geological processes would remain live long enough for them to close up, rather than becoming frozen in place.  Vanadar’s Hoos, if it had any, were probably shorter lived than those on Earth, taking longer to form, and dissipating more quickly, and probably being smaller.  The polar openings, if they formed, were probably much smaller and less stable than those on Earth.

That being said, perhaps we can extrapolate on the geography of the interior, from considering the surface.

The major event for Vanadar, as with Thanator, were probably the twin impacts close together which tilted the planet off its axis.   These impacts obviously didn’t punch through the moon.  But if they were intense enough that their shockwave traveled through Callisto and produced the White Mountains on the opposite side, then I think we can assume a similar shockwave impact on the inside.

Thus, Vanadar probably has an area of ferocious uplift, probably similar to Tharsis on Mars.   There are probably two titanic mountains or volcanoes, sitting at the center of a complex of volcanoes, Extreme Cliffs, towering mountain ranges, and ferocious chasms radiating outward from the impacts like entangled spider webs.   The force of the impact would have sent boulders and mountains flying like a shotgun blast, peppering a large part of the interior with debris.  In short, nasty disordered territory.

Opposite, there would be another jumbled complex of mountains and cliffs.  This secondary complex would lack the signature twin supermountains, and the explosive burst of debris.  It would be more jumbled and disorderly

The impacts shifted Thanator off its axis, causing its old poles to drift and new poles to orient.  The result topside was two seas, the Corund Laj and Sanmur Laj, whose shapes are distorted by the stresses of the worlds revolution.   If there were polar openings, the sites of Corund Laj and Sanmur Laj were probably it.   These polar openings would have been smaller, and its possible that they closed naturally, or that their relocation closed them.  But it is likely that there is still some connection here between inner and outer worlds, and an intrepid Thanator submariner might well make it into Vanadar.

The Corund and Sanmar Laj seas are probably the melted remains of polar caps, so if there was a connection, or if there still is, then those areas would contain two of Vanadars three small seas.   These seas would be the inner growths of polar glaciation melted to liquid water.

The twisting and distortion that we saw topside is probably more extreme here in the underworld where curvature piles rock on top of itself.   The shapes of the interior seas are probably those of distorted spiral starfish or octopus with long tendrils reaching out, surrounded by savage lines of cliffs and mountains, even more extreme and tortured than those found surrounding the surface seas.

And the third sea?  Well, Vanadar is tidal locked, always presenting the same face to Jupiter.  On the surface, tidal moisture is drawn to the front of the planet, closest to Jupiter, supplying the Grand Kumala rain forest with its water.    On the interior, water will be drawn the same way, so directly opposite the Grand Kumala on the underside closest to Jupiter, you’ll find a small sea.  Or perhaps not so small.   While the former polar seas are probably slowly emptying and losing their inherited waters, the central sea, encouraged by Jupiter’s gravitational tidal tug is probably slowly growing.

It is not clear whether there are openings at the site of the new poles.  It appears though that one pole is frozen over, the other is not.  We have no explanation externally why one pole should be different from the other.   Perhaps the explanation lies internally, in which case, we can assume that there is one new opening at one of the poles.

Despite all this talk of seas, Vanadar is probably a comparatively waterless place.   Earth’s and other planets water comes from comets.  Obviously, very few comets strike the inside of a world.   Rather, water reaches the interior world through atmosphere exchange with the exterior.   Thus, the interior is always dryer.   We see this with Pellucidar, where despite constant Hoos and permanent polar openings only 1/3 to 1/2 of Pellucidar’s surface is covered by water.   For the Moon, the surface is dead and dry, its waters long lost to space, but the interior waters are preserved, and amount to only three small seas.   We know that on Thanator, there are only two seas, a large lake and the polar cap which constitute its water.  Perhaps 20% of the world’s surface.   So, perhaps at best, only 10 or 15% of Vanadar is water covered (though it may actually be  more, given the really lopsided ratios of inner and outer surfaces).

So, what’s it like on the interior.   I’m thinking pretty nasty.   We know that both Va-Nah and Pellucidar have inner ‘stars’, most likely dwarf black holes which the planet forms around like a shell.   Its likely that in the Burroughs universe, this is the mechanism for the formation of small worlds like Earth and the Moon.  So if Vanadar exists, then it probably has such a ‘star.’

What’s Vanadar’s star like?   Pellucidar’s burns perpetually radiating light and heat.  Vah-Nah’s star is invisible, producing gravity, perhaps radiating heat, but not light.   Vanadar’s star is likely more similar to Pellucidars, it’s potentially a bright, warm body.  As to how much heat or light it might radiate, and what sort, its hard for me to guess

But there’s another special factor to Vanadar’s star.  The thing is a magnetic powerhouse.  It radiates a magnetic field powerful enough to light up the outer atmosphere like a neon lamp, and help to provide heat as well.   What does this mean for the star of Vanadar?  Well, Earth’s ‘star of Pellucidar’ generates a powerful magnetic field, though not nearly as powerful as this Vanadars. It’s not clear what sort of magnetic field Vah-Nah’s star generates.  But on a guess, I’d say that strong magnetic fields may be related to strong light output, perhaps light in the higher ranges up to ultraviolet.

What does it mean for the interior?  Well, it suggests that Vanadar is extremely hot and bright, both for the star’s output and for the side effects of its magnetic field.  Perhaps significantly hotter and brighter than the surface.   Indeed, it may be so hot and bright as to be uninhabitable, a scorched wasteland whose inhabitants cower in eternal shadows.

The magnetic output may make things interesting in other ways.  The intense magnetic output may have electrical effects.   Think of mountains constantly discharging lighting at each other and at the sky like those static generator balls.  Think of a floating electrical potential so that as you walk around, you begin to accumulate your own St. Elmo’s fire glow.

A hotter more volatile interior world may see much more moisture being perpetually liberated into the atmosphere.   After all, extremely hot conditions from the ‘star’ radiation and magnetic side effects may literally boil water.  A lot of the interior’s water may be up in the atmosphere and Vanadar may have a very intense hydrological cycle.  Atmospheric water rises and forms clouds which blot out the sun, causing thermal differentials.  The mountains constantly channel the clouds around, and perpetual flash flood torrents roar down mountain channels.

Throw in ferocious winds and you’ve got an interesting forbidding and strange land.  Changeless land of extreme contrasts, an ever burning sun, sheer cliffs, perpetual lightning and ferocious sudden rain storms.

What sort of things live there?   I wouldn’t venture to speculate, let someone else populate it with plants and animals if they’re so minded.   I do offer one thought...

On the surface of Thanator, we know that the Mind Wizards are alien, and that the humans are likely just as alien.  The winged cannibals and amphibians have their counterparts on other worlds, and hence probably do not originate on Thanator.

But the insectoid Yathoon have no obvious counterparts anywhere else in Burroughs or Kline.   There is no sign of an ecology or flowering of insectoid evolutionary lines which would have produced something like the Yathoon or Wells’ creatrues on either Thanator or the Moon, or for that matter, on any other world described by Burroughs or his contemporaries.

So, here’s a thought.  Perhaps the Yathoon are the original ruling race of strange Vanadar, a tribe of whom has made it to the surface.   This certainly would explain the anomaly of their presence.  Vanadar, in this case, would be a strange primeval wilderness of giant insects of every sort.  Imagine beetles and mantises the size of elephants and allosaurs, and a hundred other forms, each more exotic than the last.

Is there anything that might support this notion?  Well, it seems that the hidden valley of Sargol, which is the centre of the Yathoon’s race and culture is right smack in the middle of the Black mountains, surrounded by a river of lava, and heated in what may be a uniquely geologically live area.   In short, it fits the characteristics you might look for, for a temporary Hoos which offered passage between inner and outer worlds to a wandering Yathoon population.  Food for thought.

And with that, ladies and gentlemen, I’ll leave you pondering...