I stumbled on the following published letter during a hard-drive cleanup. Note that NASA scientist James Hansen was a student of Carl Sagan.
(First published in Atlantis Rising, Letters section, No 32, March/April, 2002).
John Kettler notes that Carl Sagan led the rigged 1974 AAAS meeting in San Francisco (Symposium on Velikovsky’s Challenge to Science) which was designed to bury Velikovsky’s claims once and for all.
What was Sagan’s interest in Velikovsky?
Empirical science gathers facts, proposes theories that explain the facts and uses the theories to predict additional
facts. Finding a predicted fact verifies the theory which then itself becomes a scientific fact that can be used as a basis for additional theories.
Velikovsky, using historical records, theorized that Venus was a late addition to the solar system. The predictive fact he used as possible verification of his theory was the temperature of Venus which he claimed would be eight times the temperature of Earth.
Mass/gravity, a basic scientific fact that cuts across all scientific disciplines, uses Newtonian Mechanics to describe the solar system. Newtonian Mechanics prohibits the addition of planets to the solar system. Velikovsky’s theory that Venus was a new planet opposed Newtonian Mechanics. It could not be correct.
Given the theory’s impossibility and the improbability of Venus’s temperature ever being verified, astronomers felt safe using Velikovsky’s prediction of a hot Venus to ridicule the man himself.
Astronomers were therefore more than perplexed when Velikovsky’s prediction turned out to be accurate. Not only were they faced with the embarrassment of having an object of their ridicule proven right, the basic astronomy discipline was in danger of being discredited. Either Newtonian Mechanics was wrong, or worse, astronomical data were not subject to the empirical methodology. This later possibility was devastating because of scientific comity under which one branch of science accords uncritical validity to the scientific facts empirically verified by another branch of science. Astronomy could not afford to have its empirical conclusions brought into question within the broader scientific community.
As a result, astronomers had to take action to avoid being hoisted on their own petard, the discovery of a publicly ridiculed prediction verifying an impossible theory. Action took the form of the young, photogenic astronomer, Carl Sagan. The plan was simple: Replace Velikovsky’s prediction with one showing that Venus’s heat was empirically predictable from accepted astronomical observations made prior to its discovery.
Unfortunately, the only fact astronomers could use to predict Venus’s heat prior to its discovery was the Venusian cloud cover and no reputable astronomer could venture an explanation how Venus’s temperature, almost four times what was needed to boil water, could be predicted from its cloud cover.
That’s where the young Sagan came in. He had no reputation.
The astronomical community called one of its rare televised press conferences to feature Sagan claiming he had long known Venus was hot because its cloud cover produced a greenhouse effect that caused the clouds to trap heat just like a greenhouse traps heat on Earth. There were a number of problems with the analogy, not the least of which was the fact that clouds decrease the heat in a greenhouse rather than intensify it. If inserting a layer of clouds around a greenhouse could produce the temperatures recorded on Venus, the oil industry would have long since gone the way of the dinosaurs.
But with the world’s astronomers behind him, Sagan was able to make the analogy appear reasonable and his “prediction” replaced Velikovsky’s prediction, allowing the empirical purity of astronomy to remain intact. Sagan, in arranging the 1974 AAAS symposium, was merely putting the formal stamp of scientific legitimacy on his after-the-fact prediction, disappearing Velikovsky’s successful prediction down the memory hole of science.
With the greenhouse effect now a scientific fact in astronomy, it was accorded uncritical acceptance by other branches of science. Sciences concerned with the chemistry and physics of the atmosphere began to propose theories about the cause of the greenhouse effect, greenhouse gasses, and their effect, global warming.
The problem with this, of course, is that Sagan only created his greenhouse theory to give the appearance that Venus’s heat had been predicted by astronomy. The theory’s predictive fact had preceded the theory. Designed only to predict an existing fact, the theory was demonstrated by its assertion.
This is not exactly a rigorous application of empirical methodology and could even be called cheating. The greenhouse theory was allowed to pass the empirical test designed by the scientific method to verify theories without being required to take the test.
Having accepted an untested theory as fact, unrelated branches of science now reach easily discreditable conclusions about global warming based on the untested theory, and charges of junk science fly from every direction. An unintended result of Sagan’s effort to bury Velikovsky’s successful prediction that Venus was hot, then, was not an end to scientific controversy, but rather an intensification of it.