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Venus May Have Been Habitable, Says NASA (sciencedaily.com)
EzInKy writes: Science Daily has an article speculating that Venus may have been habitable which is suggested by NASA climate modeling, which proposes that Venus may have had a shallow liquid-water ocean and habitable surface temperatures for up to two billion years of its early history. Talk about global climate change run amok. Venus may represent a near Earth example of what is in store for the future of our world if we don't make it a number one priority to address. Science Daily reports: "Venus today is a hellish world. It has a crushing carbon dioxide atmosphere 90 times as thick as Earth's. There is almost no water vapor. Temperatures reach 864 degrees Fahrenheit (462 degrees Celsius) at its surface. Scientists have long theorized that Venus formed out of ingredients similar to Earth's, but followed a different evolutionary path. Measurements by NASA's Pioneer mission to Venus in the 1980s first suggested Venus originally may have had an ocean. However, Venus is closer to the sun than Earth and receives far more sunlight. As a result, the planet's early ocean evaporated, water-vapor molecules were broken apart by ultraviolet radiation, and hydrogen escaped to space. With no water left on the surface, carbon dioxide built up in the atmosphere, leading to a so-called runaway greenhouse effect that created present conditions."
NASA scientists need to learn the difference between evidence and simulation. There is almost no evidence to support this hypothesis -- the best that one can say for the simulation is that it shows that the hypothesis isn't overtly incompatible with the little evidence that there is. People need to read Jaynes' lovely book on the logic of science and Bayesian analysis so that they can quit confusing model consistency with model correctness. As it is, it is as if one has the hypothesis that there was a second gunman on the grassy knoll. One examines the grassy knoll and finds, sure enough, that the grass appears to have been stepped on -- there is evidence that "something" has been there. One does an elaborate computation demonstrating that yes, a sniper on the grassy knoll would have had to step on the grass in order to be there, so that the evidence is consistent with the hypothesis, and then publishes the result in the National Enquirer as proven fact (and if possible, blame the presence of the sniper on the Clintons -- after all they COULD have done it, right?).
Never mind the possibility that the grass might have been pressed down by a passing giraffe, a sleeping hobo, the lawnmower that last mowed it, or that the grass actually WASN'T "pressed down", it just grew that way. Never mind that the Clintons were in middle school at the time and would have had to fund it with lunch money, which they (obviously) shook down from other students or accepted as a bribe so that they could intervene with the teachers to get the students who paid them off A's.
Alas, that science has come to this. National Enquirer, look out!
After all, the hypothesis that Mars has had liquid oceans dates back to science fiction authors and the earliest observations of "canals". It has its own wikipedia page:
https://en.wikipedia.org/wiki/...
But even in the case of Mars, with eyes in the sky looking down through a clear, thin atmosphere and multiple landers on the ground looking for a smoking gun, we lack anything like conclusive evidence that Mars once had a liquid ocean.
Venus, on the other hand, has an atmosphere with around 100x the mass of Earth's entire atmosphere, a pressure of 90 or so atmospheres on the ground, where the temperature is only a couple of hundred degrees too cool to melt lead. It contains nontrivial amounts of several acids in its predominantly CO2 base. It is corrosive, hot, and crushing. The average survival time for the landers sent there so far is around one hour (actually, a bit less). We have something less than around 3 hours of total observational time on the ground, IIRC, all taken from dying landers with some dysfunctional bits through air a bit over twice the temperature of boiling water, before the conditions killed the lander altogether.
We have almost NO evidence from the surface AT ALL, and the little that we have contains no direct evidence that could even be VAGUELY construed as a smoking gun for oceans.
This makes me suspect that this is a fundraiser for the proposed lander missions. "Hey, maybe Venus once had a liquid ocean! Life could have developed there! Never mind that the atmosphere even a few billion years ago if anything probably had a GREATER mass and HIGHER pressures at the surface (while still being enormously hot with 40% more incident solar radiation and an adiabatic lapse rate from hell down to the surface in the dense atmosphere). Give us money! We'll go find out!"
Sigh.
Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
How did those "transmitted images" help mankind? Had we spent the billions on cancer-research or longevity or what have you instead, our lives today could've been much better. Yes, the lives of everyone, not just hobbyists interested in conditions on unreachable space-rocks.
And, in due time, we would've reached those rocks too...
Why is my real account disabled?