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KRONOS Vol V, No. 1
MORE ON THE THERMAL ASPECTS OF VENUS
To the Editor of KRONOS:
My letter with critical comments on Dr. Talbott's mathematical model of Venus seems to have triggered quite a lot of activity.(1) Dr. Earl Milton and Leroy Ellenberger dispute my statement that the difference between emitted radiation and absorbed sunlight must be small. Of course, you can always have different opinions of what is "small". Ellenberger's figures, which are consistent with the value of insolation given by Milton, give a net radiation of 1.2 x 1016 W. But in Talbott's mathematical model, the ground surface of Venus radiates 8.3 x 1018 W, which is about 700 times as much.
Talbott's suggestion that endothermic photochemical reactions may absorb a major part of the radiated energy is interesting, but I doubt that such reactions can have a significant effect on the net radiation from Venus. The chemical reactions in the atmosphere are generally assumed to be cyclic, in the sense that endothermic reactions at one place are balanced by exothermic reactions at some other place within the atmosphere. No energy is permanently bound in this way; if it were, the composition of Venus' atmosphere would be gradually changing, so that the concentration of energetic compounds would be continuously increasing. Still, this possibility should not be dismissed without a quantitative analysis. Let us assume that the photochemical processes can bind 107 J per kg, which is a high estimate. The total mass of atmosphere per square meter surface area is about 106 kg. If the whole atmosphere took part in the reactions, a theoretical maximum of 1013 J/m2 could be bound as chemical energy. Thus a flux of 1.8 x 104 W/m2 could be absorbed for a period of 5.6 x 108 seconds at the most, or approximately 17 years.*
Talbott refers to the Stefan-Boltzmann law. There is nothing wrong with this law, but it is wrong to neglect the radiation from particles in the dusty atmosphere, which follows the same law. Especially in the lower parts of the atmosphere where the temperature is high, there must be an intense radiation from dust particles. (There is also some radiation from the gases, following more complicated laws.) The radiation from the hot atmosphere must be taken into account when calculating the net energy flux from the surface of Venus. I am tempted to say that it is naive to neglect it, but it is not. It is just human. But if Talbott were right about the net energy flux from the surface of Venus, there would be no point in improving the thermal insulation of a house, because the heat flux from the house would be determined solely by indoor temperature, outdoor temperature, and the Stefan-Boltzmann law.**
Frederic Jueneman asks what would happen to my modification of Velikovsky's reconstruction if my submission to the SIS Review were rejected. This question is highly relevant, because actually, it was. This was no catastrophe, because a similar theory was published by Keister and Hamilton.(2) The authors, after discussing some difficulties of Velikovsky's theory of the expulsion of Venus from Jupiter, proposed an alternative theory whereby "Venus, formerly an obscure and remote planet in the solar system, passes close to Jupiter and is deflected into an eccentric inner solar system orbit".
My own theory was based upon a suggestion once made by Jueneman:(3) ". . . Venus may also have been a rather large satellite of the Jovian planet that had the misfortune of being caught in vortical forces by the near-encounter passage of [Jupiter and Saturn]." In my article, I showed that the disturbance causing one of the Jovian satellites to leave the family need not be as drastic as a near-encounter of two giant planets. A satellite system is not stable under all circumstances. There may be orbits so far from the planet that they must be considered semistable. There may also be intersecting orbits. An orbital instability originally created by a Saturn nova outburst may have caused changes of orbits that took place many centuries later.
The point with theories like those described here is that, while the rest of Velikovsky's reconstruction can stand as it is, we need not worry about the thermal state of Venus. However, one problem remains. There are clear indications in the myths that Venus actually came out of Jupiter. In my article, I suggested that this was an illusion, caused by a dust shell which at that time surrounded Jupiter. The editorial staff of SISR thought that this dust-shell theory should be substantiated first, which seemed fair enough to me. I thus wrote another contribution, tentatively called "Novae and Dust Shells", which is now awaiting its verdict in England.
Finally: I am sorry if I gave the impression of accusing Dr. Talbott for talking nonsense about the second law of thermodynamics. What I meant to say was that although the spontaneous formation of a thermal gradient may appear to be a violation of the second law of thermodynamics, it is, in fact, not. Dr. Talbott never mentioned the second law of thermodynamics.
1. "On the Thermal Aspects of Venus", KRONOS IV:3 (Spring 1979), pp.76-86.
Leroy Ellenberger Replies:
Dr. Talbott, being absorbed in further and additional researches, has prevailed upon me to comment on this second letter from Mr. Forshufvud. It would appear this vigilant Viking possesses the persistence of a woodpecker with tunnel vision. He keeps hammering away at one small knot with apparently little, if any, awareness of the forest. That Talbott's model predicts a present cooling rate about 700 times greater than that deduced from rudimentary heat balance calculations has already been noted in the first round of replies. This discrepancy does not, however, vitiate Talbott's model. Its beauty, which appears lost on Mr. Forshufvud, is that the two equations Talbott used could realistically model the cooling history of any large primordial cosmic body over such time and temperature ranges.
Assuming that Talbott's model was valid up until some recent time and that Venus is still cooling, the present variance merely indicates that conditions have changed so that a modification would be needed to model the slower cooling in the present epoch. This would be the case if volcanism were not as extensive as formerly. In light of both the foregoing and the necessary limitations of any model, the computations in the second paragraph, though correct, constitute excessive pecking.
At the risk of being repetitious - regardless of what deficiencies are ultimately confirmed in Talbott's model, Mr. Forshufvud's preoccupation with minutiae obscures the nature of the model's elegance and true importance: It is the first rigorous, scientifically respectable model of Venus' thermal history that ineluctably ties her present measured surface temperature to her having been red hot 3,500 years ago, thereby lending quantitative respectability to Worlds in Collision. Its immediate motivation was the slick, but erroneous, "cooling computation" presented by Carl Sagan in Appendix 3 of his analysis of Worlds in Collision. Considering Mr. Forshufvud's concern for a model's validity and accuracy, one wonders how many letters he has posted to Ithaca.
Talbott's model was never intended to preclude detailed models of the atmosphere. Indeed, solar insolation was explicitly assumed to be negligible. If one is not satisfied with his results, the next level of refinement worth considering is a layer-by-layer, wavelength-by-wavelength model of the atmosphere from the cloud tops to the surface. This is because the dynamics are so complicated that approximations cannot be trusted to produce sufficiently accurate results at this time. Even NASA scientists have not published the results of such a model, if indeed such a model exists. Mr. Forshufvud's concerns are simply misplaced rigor, not unlike the engineer struggling for the third decimal place when one is all that is required.
In the third paragraph, Mr. Forshufvud's analogy between the heat loss through Venus' atmosphere and that through the walls of a house is simply invalid. The modes of heat loss are completely different. The atmosphere loses heat by convection and radiation while the wall in a well-insulated, air-tight house loses heat predominantly by conduction. The Stefan-Boltzmann law governing radiation is, therefore, not appropriate for calculating the heat loss through the walls of a house.
The atmosphere of Venus may work "as a rather good thermal insulator" as Mr. Forshufvud states, but then only because of its thickness, not because of any intrinsic insulating properties. Conventional four inch walls would have to be fifteen inches if insulated with material having the thermal conductivity of Venus' lower atmosphere. Also, based on Pioneer-Venus data referenced in the first round, the lower atmosphere of Venus is essentially dust-free. Therefore, Mr. Forshufvud's concern about radiation from dust would appear to be quite misplaced.
Jueneman's rhetorical query about the possible rejection of Mr. Forshufvud's paper by the SIS Review was right on the mark and it is considerate of him to share the outcome with KRONOS. Having been up-staged, so to speak, by Keister and Hamilton is scant consolation considering the plethora of deficiencies that could be identified in their paper: an inadequate literature survey that ignores Sherrerd's earlier work, Hamilton's own paper on the circularization of planetary orbits, Juergens on bulk chemistry and Crew on the ejection of solid core material from gaseous planets; an erroneous dismissal of Jupiter as a candidate for a Lyttleton-type fissioning; a confused discussion of Jupiter's moment of inertia; and a misperception of Jupiter as entirely compressible, thereby denying the highly probable existence of liquid hydrogen below the atmosphere. Less violent alternatives than the fissioning of Jupiter are acceptable to explain the arrival of proto-Venus, but it is too soon for them to be asserted at the total expense of fissioning processes.
Finally, I would like to acknowledge that in KRONOS IV:3 I erroneously criticized Mr. Forshufvud for having written that ". . . after solidification, the cooling at the surface would go much quicker" than indicated by the Stefan-Boltzmann law. On this point he is correct, if large-scale volcanism is absent. Because his statement is unreferenced and unquantified, its origin is uncertain. I would point out, however, that the relationship between cooling rate and surface temperature is not the sixth power proportionality asserted by Morrison in Scientists Confront Velikovsky, p.161. The correct solution to this problem of the cooling of a surface by conduction and radiation in series is more complex than implied by Morrison and is given by Özisik in Boundary Value Problems of Heat Conduction (Scranton, PA., 1968), pp.319-323. Additional discussion on this solution may be found in the replies to Morrison forthcoming in this journal.
Having answered Mr. Forshufvud yet once again, perhaps we can now proceed with more fruitful pursuits.
* * *
The Editor Comments:
In the event that Mr. Forshufvud is still not satisfied by the latest response to his criticism of Dr. Talbott's thermal model of Venus, he will have to content himself with agreeing to disagree. It would seem that Mr. Forshufvud's misgivings have arisen from the fact that he perceives the thermal state of Venus as either irrelevant or problematic re Velikovsky's cosmological scenario, and he is attempting to circumvent that supposed problem through an alternate theory. However, his line of reasoning and argumentation suffers on three counts:
(1) A delusional attitude that the temperature of Venus is somehow irrelevant to Velikovsky's cosmological reconstruction when, in fact, Venus' thermal state appears to be not only a direct corollary of the events described in Worlds in Collision, but was already anticipated by Velikovsky on the basis of the detailed documentation he presented in that book. While a circumvention of the temperature problem might serve to avoid a head-on confrontation with people like Sagan and Morrison, who find it necessary to press their case for the Venus greenhouse effect with so much vigor, a stance such as that assumed by Forshufvud on the thermal question is strongly at odds with the historical evidence set forth in Worlds in Collision; and thus Forshufvud's own theory is totally divorced from the very data he seeks to substantiate.
(2) An erroneous assumption that Venus' thermal aspects may pose some difficulty for Velikovsky. To the contrary, the Pioneer-Venus probes have only left Establishment Science with newer and greater perplexities, many of which were enumerated in the previous issue of KRONOS (IV:4, pp.1-15). Furthermore, Forshufvud and other skeptics (e.g., Morrison) would be well-advised to read V. A. Firsoff's excellent article – "On Some Problems of Venus" – in the Journal of the British Astronomical Association, 89, 1 (1978), pp.38-46. For the most part, the questions raised by Firsoff still remain unanswered.
(3) An uncritical posturing towards a theory put forward by Keister and Hamilton (SISR III:2, pp.45-48) – a theory that Forshufvud endorses only because it is similar to an abortive one he himself wished to propose. Unfortunately for Forshufvud, the Keister-Hamilton model is a weak reed to lean on. It is virtually a cosmological dead-end with neither a demonstrable beginning (by the authors' own admission) or satisfactory conclusion. In addition to the shortcomings enumerated above by Ellenberger, it also fails to take into account the theoretical research of Rose and Vaughan, Alfvén and Mendis, Oort, Vsekhsviatskii, Ovenden and Van Flandern. Moreover, the Keister-Hamilton model does not square with some of the fundamental aspects of Worlds in Collision.
As though the preceding were not enough – and enough it is – three additional (final?) points deserve mention. (a) Worlds in Collision presents much evidence that Venus appeared red in the sky over a long period of time; and it strains the bounds of credulity to suggest (as do Keister and Hamilton) that a Jovian close encounter, by an ice-encrusted wanderer, could initiate the physical processes necessary to sustain the kind of fiery display seen and reported by the ancients so many centuries, even millennia, after Venus' birth; (b) In their speculations about the electric field generating potential for a proto-Venus/Jovian encounter Keister and Hamilton neglected the fact that a body moving past Jupiter toward the Sun, at their posited 50 km/sec, would be traveling at hyperbolic velocity. As such, it would escape the Solar System because, at Jupiter's orbit, escape velocity from the Sun is only about 20 km/sec. Needless to say, in this instance, the present question of Venus' origin is rendered somewhat less than academic; (c) In their reply to earlier criticism by Ellenberger (SISR III:4), Keister and Hamilton felt that Eric Crew "should be able to relate his ideas much more closely to those of others in the field". They then proceed to refer Mr. Crew to two sources that were published after his own work had already appeared. This is a rather high expectation from researchers who are inexcusably lax with regard to both standard astronomical and Velikovskian literature published prior to their own work. For example, while citing Bass' "'Proofs' of the Stability of the Solar System", when confronted with the problem of orbital circularization, K & H omit any reference to Bass' other work in Pensée VIII ("Did Worlds Collide?") and KRONOS 1:3 ("Can Worlds Collide?"). Indeed, the last two named would have been even more appropriate, apart from the previously cited omissions.
If there is an alternative to the ejection of Venus from Jupiter, the Keister/Hamilton model is not it.
A final point of interest has to do with Forshufvud's earlier position regarding the origin of Venus. In a letter to Pensée (II, Fall, 1972, p.46), Forshufvud had this to say with respect to the Great Red Spot on Jupiter: "...I propose a reconsideration of the solid-body hypothesis. How could a solid body be floating in the atmosphere of Jupiter? My answer is: by electrostatic repulsion .... Now, if Venus was electrically charged, Jupiter must also have been electrically charged, and the force that allowed Venus to leave Jupiter may have been, quite simply, electrostatic repulsion [Cf. Crew, KRONOS III:1, p.23]. If you calculate the voltage Jupiter must have had to make this possible, you arrive at something on the order of 1019 volts. If Jupiter had this high voltage, it probably has about the same voltage today. This could explain how a solid body is able to float around in its atmosphere .... The Greeks used to say that Athena sprang out of the head of Zeus, which is to be interpreted as a description of the fact that Venus was expelled from Jupiter. Could the red spot mean that Zeus is pregnant again?"
Considering his reference to an earlier (1975) "suggestion once made by Jueneman", it is curious that Forshufvud could have forgotten his own.