This forum is about wrong numbers in science, politics and the media. It respects good science and good English.
One of the recent probes exposed the fact that the solar wind was stripping out all the other gases from the atmosphere leaving the heavier molecules like CO2. The primary reason being a lack of a liquid core which is what generates our own protective magnetic field.
I don't want to say anything bad about Sagan, but he seems to have found a couple of ways to leverage Mencken hasn't he. I can't blame him there either. It's akin to the Publish or Perish mantra. If you don't stay visible somehow, you won't be on the speed dial.
NASA didn't like the temperature data?
Sound like they'd have been at home in Chernobyl.
The Nov 1980 New Scientist article "The mystery of Venus' internal heat" is too old to be available online, but I managed to find the text for it:
"Two years surveillance by the Pioneer Venus orbiter seems to show that Venus is radiating away more energy than it receives from the sun. If this surprising result is confirmed, it
means that the planet itself is producing far more heat than the earth does.
F.W. Taylor of the Clarendon Laboratory at Oxford presented these measurements at a Royal Society meeting last week. Venus surface temperature is higher than any other in the
solar system, at 480 C. The generally accepted theory is that sunlight is absorbed at Venus' surface, and re-radiated as infrared. The later is absorbed in the atmosphere, which thus
acts as a blanket, keeping the planet hot. It is similar to the way a greenhouse keeps warm.
Pioneer has shown that there is enough carbon dioxide and the tiny proportion of water vapor needed to make the greenhouse effect work -- just. If this is the whole story, the total
amount of radiation emitted back into space, after its journey up through the atmospheric blanket must be exactly equal to that absorbed from sunlight (otherwise the surface temperature would be continuously changing).
But Taylor found that Venus radiates 15 percent more energy than it receives. To keep the surface temperature constant, Venus must be producing this extra heat from within.
All the inner planets, including earth, produce internal heat from radioactive elements within their rocks. But Taylor's observations of Venus would mean that the planet is producing
almost 10,000 times more heat than the earth, and it is inconceivable according to present theories of planetary formation, that Venus should have thousands of times more of
the radioactive elements than Earth does. At last weeks meeting, Taylor's suggestion met with skepticism - not to say sheer disbelief - from other planetary scientists.
Taylor himself has no explanation for his result. He simply points out that the discrepancy seemed at first to be simply experimental error - but with more precise measurements, it
refused to go away. More measurements are needed before astronomers accept the result, and most planetary scientists are obviously expecting - and hoping - that the embarrassing
extra heat will disappear on further investigation."
Now in the UK we have operated a type of nuclear reactor called the 'Magnox' reactor. It uses natural uranium fuel (0.7% U235, not enriched), a carbon (graphite) moderator and high pressure carbon dioxide as a coolant to take heat away. The way I see it, Venus with its high pressure CO2 atmosphere may not be that different to a sort of naturally occurring Magnox reactor. The CO2 would permeate the Venus soil and could act as both a moderator and coolant for uranium ore deposits on Venus.