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KRONOS Vol III, No. 2
THE VENUS "GREENHOUSE THEORY" –DEBUNKED
Lewis M. Greenberg
In 1950, Velikovsky (Worlds in Collision, p. 371) claimed that Venus was hot due to its violent history, its Solar approaches, and its residual natal heat. Contemporary scientific opinion of the time envisioned Venus as being only slightly, if at all, warmer than the Earth. On the basis of the calculated greenhouse effect, the surface temperature of Venus was estimated to be about 100 degrees C above the radiative-equilibrium temperature.
When space probes of the late 1950's and early 1960's revealed that Venus' temperature probably exceeded 400°C,(1) it was realized that the greenhouse effect alone could not account for such heat. Therefore, an "enhanced" (C. Sagan, Astronomical Journal, 65, 1960, 352) and "runaway" (S. I. Rasool and C. de Bergh, Nature, 226, 1970, 1037) greenhouse effect were postulated, with the assistance of hypothetical water vapor.
In 1973, however, M. A. Janssen and several colleagues of UCLA-Berkeley reported that they could find "no evidence of water vapor in the lower atmosphere of Venus . . . . it remains to be shown that a 'greenhouse' mechanism can be supported with the present constraints on the water vapor content" [Science, 179, 994, March 9, 1973; also see Pensée V (Fall, 1973), p. 27; KRONOS 1:4 (April, 1976), p. 90].
The Nov. 3, 1975 issue of Aviation Week & Space Technology, in reporting on the two Russian Venus probes–Venera 9 and Venera 10, commented thus about the Venus greenhouse theory: "Data and photographs returned from Venera-9 and -10 Soviet Venus lander spacecraft portray a well-lighted rocky surface belonging to a young, evolving planet ... Venus is a planet in an early cool-down phase of evolution rather than in a final stage of suffocation in a thickening atmospheric greenhouse" [See KRONOS I:3 (Nov., 1975), p. 85; KRONOS 11: I (August, 1976), pp. 104-105].
Adherence to the belief in a supposed runaway greenhouse effect, in order to explain Venus' high temperature, has led to some rather strained reasoning on the part of professional astronomers. Consider, as an example, the following statement by Lloyd Motz from his 1975 book titled The Universe – Its Beginning and End:
With regard to Venus' heat and the runaway greenhouse theory, Jueneman has already raised a crucial question. "With a runaway greenhouse phenomenon that has been going on for untold eons, one is left to inquire why Venus still has any atmosphere left. Over the hundreds of millions, if not billions of years that Venus is supposed to have been circling the sun in its self-same orbit, this greenhouse effect would have had the tendency to void the planet of any atmosphere whatsoever, except for some nominal residue" [KRONOS 1:3 (Nov., 1975), p. 791.
In line with the above remarks, Firsoff (The Interior Planets, London, 1968, p. 103) had this to say: "An adiabatic atmosphere of a mass envisaged by Sagan [and now approximately doubled by Venera findings] is possible only if it is heated from below. In other words, the surface of Venus would have to be kept at a high temperature by internal sources. If this were so, Venus would have been still hotter in its aphroditological past, and its atmosphere would have been lost by molecular dissipation even more effectively than was the primitive atmosphere of the Earth ... [Cp. Jueneman]. It would also have had less chance to evolve and retain [a] secondary atmosphere if only comparable to our air. But the present-day hot surface condition appears impossible in any case. Both planets will be of the same age and the same general mineralogical composition, which implies a comparable rate of liberation of radioactive heat [Cp. Velikovsky, Yale Scientific Magazine, April 1967, p. 101]. As we have seen . . ., the heat liberated in the Earth's crust makes no significant contribution to its surface climate, and the oceanic depths are cold. Nor is there any indication that things are significantly different on the other terrestrial planets." So Firsoff found the answer, then rejected it as unthinkable.
Juergens, too, has pointedly summed up the fundamental weaknesses of the Venus greenhouse theory. "As of today, two of the most important postulates of the greenhouse model–sunlight of consequence reaching the surface of Venus, and water vapor of detectable quantities in the lower atmosphere of the planet–remain questionable. And there is another problem, seldom mentioned by proponents of greenhouse hypotheses, that is just as important to the maintenance of their stance.
"Were sunlight actually the source of the heat of Venus, the input of energy would always be confined largely to the sunlit hemisphere. Since Venus rotates so slowly that one of its nights is as long as two months on Earth, it is reasonable to expect, as I. I. Shapiro has pointed out (Science 159, 1124, 8 March 1967), 'larger temperature differentials between day and night' on Venus than on Earth. Even if some of the heat were convected and conducted to the dark side of the planet, considerably less than 100-percent efficiency would characterize the process. The dark side would necessarily remain cooler, on the average, than the sunlit side. Yet this is apparently not the case" [KRONOS 1:4, pp. 90-91].
As Velikovsky has succinctly put it: Many scientists cling to "the completely unsupportable hypothesis of a greenhouse effect as the cause of Venus' heat, even in violation of the Second Law of Thermodynamics" [See "My Challenge to Conventional Views in Science" elsewhere in this issue; Van Nostrand's Scientific Encyclopedia (4th ed., Princeton, 1968), p. 1840; Pensée I, "Is Venus' Heat Decreasing?" (May, 1972), p. 51].
The greenhouse model for Venus has been ridiculed by no less than Russian cosmologist S. K. Vsekhsvyatskii, head of the Kiev Observatory [KRONOS II:2 (Nov., 1976), p. 54], as well as British astronomer V. A. Firsoff [KRONOS I:4, p. 921. Additional greenhouse problems have been noted by Ransom [The Age of Velikovsky, pp. 118-121, 231; See also Optical Spectra (Dec., 1975), p. 10].
Since the proposed greenhouse effect for Venus is so problematic, why do people like Sagan, et al. still cling so tenaciously–almost desperately–to the runaway greenhouse theory as a means of accounting for Venus' hellish heat? The answer is quite simple. At present, the most logical and plausible theoretical alternative is Velikovsky's explanation–"The reflecting, absorbing, insulating, and conducting properties of the cloud layer of Venus modify the heating effect of the sun upon the body of the planet; but at the bottom of the problem [of Venus' heat] lies this fact: Venus gives off heat"; and because this heat is primordial, arising from Venus itself, "the core of the planet Venus must still be hot" (Worlds in Collision, p. 371–emphasis added)–but this is an explanation that the scientific community is unwilling to accept. What, then, is the solution–a "runaway, runaway, runaway" greenhouse effect? This sounds more like a current popular song than a serious scientific hypothesis.