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Prospects for a Rogue Earth Advanced Technical Civilization

Richard Brook Cathcart
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Geological discovery of Earth-life that never sees the light of day because it is native to our home world's rocky sub-surface, together with the recent astronomical discovery of planetars, which are planets freely roaming interstellar space, portends a drastic change in humankind's outlook on life in this Universe. This report discusses the thermodynamics of a future Homo sapiens sapiens-style civilization macro-engineered to exist as a roving unbound planet (UBP), with the aim of outlining its essential characteristics. Offered is a physics-grounded assessment of its true worth as a moving abode named "Ballardia", a minimal human population civilized life survival capsule (extinction refuge) powered only by lithosphere-generated energy capable of compensating for a 211 K reduction of surface temperature.


Unbound planet (UBP) Earth, underground world-Anthropostrome, rogue planet human extinction refuge


Bold contemporary bio-astronomers perceive outer space imbued with the expectation of spying grand-scale alien technologies. But, their 21st century colleagues have only hopeful biological hypotheses the Universe's stars are "shipyards" creating, amongst other objects and energies, planetars moving through outer space's vastness, possibly carrying various forms of life. During 1958-62, Harlow Shapley (1885-1972) initiated the controversy of "stray planets" and runaway crusted stars (also known as "brown dwarfs").

During 1951, Richard Buckminster Fuller coined a new descriptive for Homo sapiens sapiens' Earthly world-anthropostrome – the total ensemble of artifacts in which humans are intimately enmeshed – when he coined "Spaceship Earth". His useful phrase is an encompassing geographical label as well as a geo-philosophical viewpoint on the human-made segments of the Earth-crust defined by the operational range of our most powerful crust-penetrating machines.

If an Earth-like unbound planet (UBP) or a planetar has any kind of vitality within its minimal gravitational control, then it is logical to call it a "Spaceship": it is a planet-vehicle! Civilized life therein might direct its planet-vehicle inheritance for maximal advanced technical civilization longevity. Just before the Sun becomes a red-giant stage star 4–5 billion years hence, the odds that our particular homeland, Earth, will be ejected into interstellar space – becoming a rogue planet – are approximately 1 in 400,000. Were Earth to become a UBP "today", its tectonic plates would move faster, hastening the natural event-process shutdown expected in 2.5 × 109 years, for without sunlight its crust would be much cooler than "today" (245 K); more rapid heat flow from the core-mantle to the crust will also then occur.

At least two science-fiction novelists have published on the topic of Earth as a future, near contemporary, free-floating independent planet, a "UBP Earth". Stanley Schmidt's Lifeboat Earth (1978) and David Dvorkin's Central Heat (1988) offer only sociological descriptions; Schmidt conjures alien-supplied propulsive devices used to move Earth away from an impending Milky Way Galaxy core radiation hazard, while Dvorkin let aliens steal our Sun for some unknown reason, causing a climate catastrophe, the "death" of the Earth-atmosphere. (Realistically, even without energizing sunlight, Earth's atmosphere will retain its basic air circulation features for ~50 days!) In both instances, civilized life continues, but only after becoming a machined part in an Earth made into a motorized UBP.

Souterrains extraordinaire

Only two methods of conserving our world-anthropostrome have been proposed: (1) armoring the sub-aerial Earth-crust with a James Graham Ballard megastructure-style big building constructed with anthropic rocks or (2) burrowing beneath our world-anthropostrome, duplicating and ramifying its life-support functions underground. Between the 1st and 5th centuries, people living in what is today Scotland built their villages encircling a main subterranean cavity that corralled and protected cattle, their most valuable possession; such community centers are named "souterrains" by archaeology.

Long-term occupancy and use of mined space has an extended history worldwide because the energy conservation factor achieved through the use of the insular qualities of rock ceilings and walls permits a variety of purposes, especially when floors allow unlimited equipment installations or storage weight; excavation of sub-surface rooms carries the attributes of the extremely vulnerable skyscraper in an inverse direction.

Examined in terms of their ontology, geometry, the part/whole relationship, identity, causality functions and the way in which humans generally perceive them, "holes" were the nearly metaphysical subject of Roberto Casati and Achille C. Varzi's Holes and Other Superficialities (1994). Patterned holes bored into the Earth-crust can impede the passage of ground-shaking surface waves such as earthquakes caused by rapid tectonic plate movements. Assuming natural Earth-crust porosity as ~3%, its top 5 km has 2 × 107 km3 of "holes" (voids within natural, pre-Homo sapiens sapiens rock) that are actually filled with highly pressurized fluids, gases and life forms beneath the landmass alone; the volume of vacant intra-rock space can be increased technologically. Scientific research shows that even rather common bacteria can survive pressures equivalent to those found ~50 km beneath Earth's rocky surface. Unlike large asteroids, planets cannot be hollowed and so Islands in Space: The Challenge of the Planetoids (1964), by Dandridge M. Cole and Donald W. Cox, provides little relevant guidance for our global-scale macroproject plan. However, we find it comforting that macro-engineering has made significant strides in assessing the true conditions for future global excavation of appropriate Earth-crust regions – certainly, the 28% that is landmass – by way of subway constructions: a globalized network of subway tunnels may become the rhizomes of a new terriculous advanced technical civilization in an Earth that is a wandering UBP. Thus, there is some need for "Deep Thinking", not merely "Deep Ecology"!

Earth's area is ~5.5 × 108 km2. Sheltered beneath a thin atmosphere with a thermal resistance of 0.8 BTU, its sub-aerial crust acts as a hard shell. If a 1.27 cm-thick Bubble Wrap, or something of equal insulation quality, were conformably overlaid to isolate the land and ocean, then it would take at least twelve layers of this manufactured material to achieve that thermal-isolation goal. However, if a molecular nanotechnology-instigated thick stratum of homogenous "gray goo" sheathing the entire Earth surface was emplaced, then that would accomplish the goal equally well, and have the advantage of on-site self-creation. A 1.5 m-thick "gray goo" envelopment of Earth with managed, self-repairing packaging material will have the same volume as the aggregated pore space of that 5 km-thick Earth-crust alluded to previously! James Lovelock's Gaia advocates suspect Earth is an intelligent organism, but an AI gray goo would be provably intelligent, at least collectively we might call it a "semi-sentient robot" governed by Homo sapiens sapiens sociologists. Of course, benign gray goo did not enter (the slightly incomplete) thermodynamic calculations of John Heaver Fremlin (1913-95) when he devised his 1964 solution for maximizing the human populace confined to Earth within a multi-storey epidermal world-anthropostrome.

Geochemical macro-engineering will soon be practiced on a global scale. Initially, it seems reasonable to expect that molecular nanotechnology will tailor its microscopic workers – the first macroscopic "self-repairing and self-sustaining system", USA Patent 3,274,401, was granted to Richard R. Landers on 20 September 1966 – to devour contaminative garbage buried everywhere by messy people in mapped and unmapped landfills. In other words, Homo sapiens sapiens will clear and clean the surface before we wrap it or dig deeper into it. Besides the obvious effect of restoring the surface – namely, stopping additional ground water pollution-cleansing will prepare the surface for its selected albedo change. In addition, and imitating the intelligence of God (Isaiah 40:4), human-created molecular nanotechnology's automated machines will smooth the muck (or spoil heaps) and, thereby, prevent sudden, unplanned uneven material redistributions (landslides caused by slope instabilities). Modern recyclers already label landfills as "human-emplaced ore bodies". After the planet's total packaging, Homo sapiens sapiens may wish to further transmogrify gray goo into a "black goo" cover for the purpose of energy absorption; a UBP Earth, coated with black goo, then becomes a black body, perhaps even a known form of universal dark matter!

As our species descends into the Earth-crust, extending its single-society world-anthropostrome vertically, it will be necessary to carefully define our new and unusual geological surroundings. War has often been the most important driver for the exploitation of underground artificial cavities, as Alexander Barrie's War Underground: The Tunnellers of the Great War (1961), N.J. McCamley's Secret Underground Cities (1998), Kenneth D. Rose's One Nation Underground: The Fallout Shelter in American Culture (2001) and Tom Vanderbilt's Survival City: Adventures Among the Ruins of Atomic America (2002) demonstrate. We foresee that peace maintenance will become the primary, and possibly (under a J. G. Ballard-style developmental scenario) perhaps only, sociological survival stimulus; global subway system construction will be the chief symptom of this change of heart and will. Such public mass-transit technology, along with the use of geothermal energy, is already Green-approved!

Ecological revolution

An UBP Earth would be remarkably different from the world-anthropostrome we are familiar with on a daily basis. The absence of external energy provided by the Sun would mean geology's gradational processes (aqueous, aeolian, glacial) would also be absent – weather and exposed sub-aerial living organisms no longer extant. Thereafter, only geological effects mostly stimulated by internal thermal energy will be effective in changing UBP Earth: volcanism, diastrophism, anamorphism, tectonic plate movement, polar wandering, metamorphism, and geomagnetic energy; still, its total heat, generated in a demarcated rest frame, has a corresponding inertial mass. After the Sun's termination as living Earthlings main energy source, our native homeland could still support bacterial subterranean life; will it also be capable of housing and feeding Homo sapiens sapiens?

Sunlight's absence forces Earth's surface temperature to become ~34 K – even during the postulated very harsh first-onset of a "Snowball Earth" period this planet's mean global temperature got to ~225 K – meaning the atmosphere will condense, forming an inconsistently thick draped stratum of solidified gases ~10 m-thick on the land and sea surface. Earth's atmosphere consists of 78% N2, 21% O2 and 1% other gases; the first substance to freeze would be H2O, followed by CO2, then N2 and finally O2. The pressure on the sub-aerial crust (1 atmosphere) will remain the same but the 10,329 kg/m2 will be in the form of solids, not gases. (Subsequently, Earth's world-ocean will commence to freeze, completing that phase transition in ~0.5 × 106 years. Without liquid water the tectonic plate motions would cease just as soon as all previously entrained water was lost, and without wet subducted tectonic plates, no active volcanism!) All of this grainy, sometimes slushy, but loosely bound frozen material can still be retained at the equator because the gravitational force is greater than the centrifugal force of the still-spinning UBP Earth. Nowadays, the total Earth-surface heat flow is ~4.43 × 1013 W, or ~87 mW/m2 for the mean surface heat flow. With a planetary mass of approximately 5.97 × 1024 kg, Earth's mean heat generation per unit of mass is ~11.1 × 10-12 W/kg. Radiogenic heat production in the continental crust alone corresponds to a total heat flow of 7.4 × 1012 W, or ~17% of the total surface heat flow emanating from UBP Earth. With a static Earth-crust, the crust would undergo thickening with mantle plumes uplifting some regions; Earth-crust bumps could be (as quickly) excavated, the materials removed and redistributed, by molecular nanotechnology's tiny bulldozers! What sort of simplified civilization might subsist on such a small energy budget? Obviously, Homo sapiens sapiens must settle the world-ocean's floor (to capture the 83% of heat flow emerging there)!

What would happen to advanced technical life in Earth if our homeland became unbound from the Sun? Or, indeed, if an advanced technical civilization therein decided to deliberately move a UBP Earth from the Sun to a younger star's orbit that might entail an extended "flight" period when a UBP Earth was un-illuminated by any star. Could Spaceship Earth be prepared for such a "flight" during a transfer trajectory? This brief sets forth a physics-grounded conjectural assessment of its true worth as a moving, and movable, unbound planet, a civilized life survival capsule, and whether this would be feasible powered only by geothermal energy. (Other, cosmic, sources of power may well be harvested to supplement UBP endogenetic energy provided by underground coal gasification and fission/fusion nuclear reactors.)

Speculated souterrain

For the purpose of satisfying the curious, we have modeled a speculative souterrain scenario for an UBP Earth of circa AD 2050. This is a thought-experiment, much like E. Brian Davies' "The Role of Astronomy in the History of Science" [Preprint 2002] in which a fictional device, namely a totally and always overcast planet's people try to learn about what's above their diverse civilizations! (If they possessed an X-15 rocket plane, however, they could collectively view the heavens via global television.)

It is a matter already of scientific speculation that Earth will become thermally sterilized, to an Earth-crust depth of >50 km, some 3 × 109 years hence when the Sun enters the early phase of its final red giant stage last days! As a gedanken experiment, let us imagine Earth as an UBP, a human-occupied rogue planet.

The very low heat flow cited above would not suffice by itself for a very populous advanced technical civilization, even one forced to enter an idle or "sleep mode" state. Steady radial heat conduction in a spherical shell (also known as, "Ballardia") with volumetric heat production must provide most of the energy needed by residents of an UBP Earth.

Consider, then, a J. G. Ballard spherical shell of thickness [ar] and inner radius [r] – try to imagine a donut-shaped figure; this torus is "Ballardia". Assume that the conductive transport of heat occurs in a spherically symmetric manner. The total heat flow out of "Ballardia" through its outer surface is [4π(r + ar)2 qr (r + ar)], and the total heat flow into Ballardia at its inner surface is [4πr 2qr (r)]. The subscript [r] on the heat flux [q] indicates that the flow of heat is radial. Since [ar] is infinitesimal, we have expanded [qr (r + ar)] in a Taylor series as [qr (r + arJ) = qr (r ) + ar dqr/dr + ...]. Thus, neglecting powers of [ar], the net heat flow out of Ballardia is given by Equation 1 [4π{r + ar}2 qr {r + ar} - r 2 qr {r}] = 4πr 2 {2/r qr + dqr/ dr} ar. If the net heat flow from Ballardia is non-zero, then, by conservation of energy, this flow of heat must be supplied by heat generated internally in Ballardia (in steady state). With the rate of heat production per unit of Earth mass [H], the total rate at which heat is produced in Ballardia is [4πr 2 pHar], [4πr 2 ar] being the approximate expression for Ballardia's volume. By equating the rate of heat production to the net heat flow out of Ballardia, Equation 1, we get Equation 2 [dqr / dr + 2qr /r = pH]. The heat balance Equation 2 can be converted into an equation for the temperature by relating the radial heat flux [qr] to the radial temperature gradient [dT/dr]. Fourier's law still applies in spherical geometry, [qr = k dT/dr], establishing Equation 3. Upon substituting Equation 3 into Equation 2, we find [0 = k {d2T/dr 2 + 2/r dT/dr + pH] OR 0 = k 1/r 2 d/dr {r 2 dT/dr} + pH], getting Equation 4. By twice integrating Equation 4, we obtain a general expression for the temperature in Ballardia, which is an Earth-bound spherical shell civilization, with internal heat production (nuclear et cetera) and in a steady state: T = pH/6k r 2 + c1/r + c2. The constants of integration c1 and c2 depend on the boundary conditions of a particular problem.

The possibility of rogue planets of roughly Earth mass in interstellar space should be taken seriously.

An UBP Earth might one day come to look somewhat like Europa, a large ice-covered white-colored moon. But, if molecular nanotechnology colors UBP Earth's surface black, would that coloration enhance an UBP Earth's chances to keep warm in the chilling environment of interstellar space? Prior to this speculative investigation, the most extreme imaginable climate change, the scientific "Snowball Earth" theory first proffered in 1992, has found much support in geological time's record; the planetary spectra of a "Neoproterozoic Earth" has been adopted as a standard in the search for extra-solar terrestrial-type planets. Some imagine the near-term future onset of a new – but not quite global – Ice Age, a geological event-process that will most certainly impact a mostly Earth-confined human advanced technical civilization! So, our speculation merely extends that theory, transforming it into a supported hypothesis.

A further extension of this speculation is the idea of "space weather", which is known to have powerful effects on human technologies. In the past, "space weather", has included influential extra-solar components such as interstellar matter that has affected Earth's life-supporting climate regimes: a passing or Earth-encountering dense interstellar cloud may have prevented the solar wind from impinging Earth, thereby causing drastic atmospheric heat loss. Even without a large reduction in the amount of sunlight reaching Earth, imposition of a dense interstellar cloud, reducing the Sun's solar wind of charged particles, might have catastrophic climatic effects even when the interstellar cloud itself is far too diffuse to interfere with sunlight's trajectory. The point is that Earth, without being an UBP, may become heavily glaciated – so much so, that Homo sapiens sapiens may have to retreat underground! In that event-process, humans will be forcefully motivated by a new Ice Age-"globalization" of a very distinctive kind! Will life for them in an extinction refuge, Xanadu, be equivalent to life in today's open-air "Cockaigne"?


1. R. L. S. Taylor, "Planets without stars: The probable abundance, nature, and significance of ISPs," Journal of the British Interplanetary Society, 54: 19-26 (August 2001).
2. H. Shapley, Of Stars and Men: The Human Response to an Expanding Universe (1958, London), pg. 56.
3. P. Passerini, "The ascent of the anthropostrome: A point of view on the man-made environment," Environment Geology Water, 6: 211-221 (1984).
4. H. Kragh, "The chemistry of the universe: Historical roots and modern cosmochemistry," Annals of Science 57: 353-368 (2000).
5. G. Laughlin and F. C. Adams, "The frozen Earth: Binary scattering events and the fate of the solar system," Icarus 145: 614-627 (June 2000).
6. K. R. Rao, "Nuclear reactor at the core of the Earth!-A solution to the riddles of relative abundances of helium isotopes and geomagnetic field variability," Current Science [India] 82: 126-127 (25 January 2002).
7. R. B. Cathcart, "Unnatural envelopment: Fieldwork on teh active tectonics of J. G. Ballard's 'Build-up" (1957)," Journal of Geoscience Education 50: 176-181 (March 2002).
8. J. R. Underwood, jr., "Anthropic rocks: made, modified, and moved by humans," GSA Today 11: 19 (November 2001).
9. F. T. Wainwright, The souterrains of Southern Pictland (1963, London).
10. n/a.
11. E. Utudjian, Architecture et Urbanisme Soutterain (1964, Paris).
12. F. Meseguer et al., "Rayleigh-wave attenuation by a semi-finite two-dimensional elastic-band-gap crystal," Physical Review B 59: 12169-12172 (15 May 1999).
13. K. Krajick, "New drills augur a great leap downward," Science 283: 781-787 (5 February 1999).
14. A. Stasenko, "The new Earth," Quantum 9: 18-20 (July/August 1999).
15. See WWW: R. B. Cathcart, "Civilization's Decay and An Unusual Biosphere Limit State".
16. R. D. Schuiling, "Geochemical engineering: taking stock," Journal of Geochemical Exploration 62: 1-28 (June 1998).
17. R. H. Marrs, "The control and correction of human induced changes in the Earth's biospheric environment-restoration ecology," Journal of the British Interplanetary Society 54: 225- (July/August 2001).
18. See WWW: R. A. Freitas, jr., "Some limits to global Ecophagy by Biovorous nanoreplicators, with public policy recommendations".
19. V. T. Trofimov and T. I. Averkina, "Engineering-geological structures: Hierarchy, types, and paragenetic series," Moscow University Geology Bulletin 51: 11-20 (1996).
20. Alan Berger, Reclaiming teh American West (2002, Princeton), 224 pages.
21. L. K. Edwards, "Urban gravity-vacuum transit system," Transportation Engineering Journal ASCE 95: 173-202 (February 1969).
22. Anon., "Energy from Earth's heat," Popular Mechanics 178: 32 (November 2001).
23. R. H. Lavenda, "Does the inertia of a body depend on its heat content?", Naturwissenschaften 89: 329-337 (2002).
24. P. F. Hoffman and D. P. Schrag, "The snowball Earth hypothesis: testing the limits of global change," Terra Nova 14: 129-155 (June 2002).
25. G. Laughlin and F. C. Adams, "The frozen Earth: binary scattering events and the fate of the solar system," Icarus 145: 614-627 (June 2000).
26. V. Badescu and R. B. Cathcart, "Stellar engines for Kardachev's Type II Civilisations," Journal of the British Interplanetary Society 53: 297-306 (September/October 2000).
27. M. Chown, "Grey-sky idea puts astronomers in teh shade," New Scientist 175: 22 (9 August 2002).
28. M. A. Garlick, "The Fate of the Earth," Sky & Telescope 104-30-35 (October 2002).
29. W. A. Traub and K. W. Jucks, "A Possible Aeronomy of Extrasolar Terrestrial Planets," AGU Geophysical Monograph 130, pp. 369-380 (2002).
30. L. J. Lanzerotti, "Space Weather Effects on Technologies," AGU Monograph 125, pg. 11 (2000).
31. W. H. McCrea, "Ice ages and the Galaxy," Nature 255: 607-609 (19 June 1975).
32.M. C. Begelman and M. J. Rees, "Can cosmic clouds cause climatic catastrophes?", Nature 262: 298-299 (27 May 1976).