Progress in science is achieved through open-minded investigation of phenomena, the acquisition of new knowledge, and the correction and integration of previous knowledge. The main obstacle to scientific progress is not general ignorance or the lack of application of the scientific method, but scientific orthodoxy. This phenomenon takes place when a certain theory, such as the current greenhouse/global warming theory, becomes so pervasive that it is unquestioningly adopted as established fact, and this â€œfactâ€ is used to hinder or even stifle further progress, and prevent critical investigation of the theory or the examination of alternative theories.
History can provide many examples. I give just one. In 1912 Alfred Wegener first put forward the idea of continental drift and he later expanded it. He proposed that the continents were once joined together in a single landmass, and that they drifted apart to their present positions. This is all too familiar to us now, but Wegener met nothing but opposition, much of it extremely hostile. His proposal had come up against scientific orthodoxy. Wegener spent the rest of his life trying to find convincing proof of his theory and in the end died on one of his expeditions. Even the theory of plate junctions, proposed by Arthur Holmes in 1920, and his later suggestion that convection currents in the mantle could cause movement in the plates, did not bring about acceptance of continental drift. It was only in the late 1950s that Wegenerâ€™s theory became generally accepted. Now, of course, it has achieved the status of orthodoxy. Woe be to anyone who might come up with an alternate hypothesis!
We may have a similar situation with the planet Venus. Until the beginning of exploration in the 1960s, little was known about the planet. The common view was that it was a cold, cloudy and wet planet. C.S. Lewisâ€™ 1943 novel Perelandia represents this understanding of the planetâ€™s surface.
The first researcher to postulate that the surface of Venus was actually very hot was Immanuel Velikovsky in the 1940s. He was ridiculed for this, not just because it flew in the face of scientific orthodoxy, but because of his myth-based methodology, which was not acceptable to scientists. In addition, he proposed that Venus was ejected by Jupiter (which he said was also hot and a radio source). After causing some planetary havoc, Venus was finally captured in its present orbit by the sun. The suggestion of such a huge catastrophic occurrence ran in the face of Uniformitarianism, the prevailing scientific view of development and evolution. We know now that both Venus and Jupiter are very hot planets, and the Jupiter is a radio source. These facts, however, have not redeemed any of Velikovskyâ€™s ideas.
Mariner 2 in a flyby in 1962 found that the surface was indeed extremely hot, and Venera 4, which landed on the planet in 1967, made the first accurate temperature measurement at almost 500 degrees C â€“ a far cry from the supposed cold and wet planet. The planetary explorations of Venus have produced facts, but they have also produced theories that are not yet proven. Nevertheless, these theories are promulgated as though they are beyond all doubt. They turn up in school textbooks as facts. The planet is described as once being like the earth, but now it is covered with clouds of sulphuric acid, and its heat is the result of a runaway greenhouse effect. Almost in the same metaphoric breath, the text goes on to warn mankind that the same thing could happen here on earth if we donâ€™t change our profligate habits.
Linking what is supposed to have happened on Venus with what might happen on Earth is a common feature in explanations of the atmosphere of Venus. It does not just happen in textbooks; it is part of the orthodoxy of Venus. This is no coincidence: the idea of a planetary greenhouse was first proposed for Venus in an attempt to explain its great heat. The term â€œrunawayâ€ conveniently captured the planetâ€™s supposed descent into hellish conditions. Only later was the greenhouse idea applied to Earth.
There are some problems with the orthodox view of Venus. First of all, the impression is given, especially in the elementary school textbooks, that the atmosphere is mostly sulphuric acid, which it is not. It is actually somewhere in the order of 98 percent carbon dioxide; only the clouds are supposed to be sulphuric acid.
Questions can also be raised about the â€œrunaway greenhouse effectâ€; these would probably be howled down by scientific orthodoxy. It is assumed that the planet was once like Earth. Due to factors such as its proximity to the sun and the absence of a moon, an Earth-like environment could not have happened in the first place. Venus was never like Earth. Another problem with the greenhouse idea is that Venus is entirely covered with an opaque layer of highly reflective clouds, the most reflective natural surface in the entire solar system. These clouds very efficiently turn back heat radiation, far more efficiently than clouds do on Earth. The extreme heat of Venus is actually internally generated.
Planetary exploration of Venus is of course incomplete. Missions to return to Venus are currently in the works, and future explorations will no doubt produce evidence that will challenge and correct the shortcomings in the current orthodox view.
Venus, therefore, is not a blueprint for what might happen on Earth. There are too many assumptions in the Venus scenario to be solid evidence. Orthodoxy aside, any global warming that is taking place here on Earth, is not and cannot be a copy of whatever happened or is happening now on Venus.
Also see â€œA Note on Global Warmingâ€ below.