From: Billy Brown (bbrown@conemsco.com)
Date: Tue Feb 16 1999 - 16:19:33 MST
Velikovsky's work surfaces from time to time in certain circles, but the
fundamental problems with it are seldom mentioned by his supporters. They
like to argue about this or that particular aspect of his theories, but they
completely ignore the real reasons why the scientific establishment
considers his a complete quack.
Velikovsky frequently advanced extravagant theories about cataclysmic events
without the faintest hint of how they could have happened. His work is long
on poetic description and mythological references, and very short on
calculations, numbers, and testable predictions. To mention just a few very
serious objections:
1) His theory of the formation of the inner solar system has Venus being
ejected from Jupiter as a result of a near-miss by another massive object.
But to lift that much mass out of Jupiter's gravity well would require far
more energy than any conceivable planetary process could provide (if I
remember the numbers correctly, the entire energy output of the sun would
not be sufficient).
1a) Where exactly did we find a large mass of solid rock in Jupiter, anyway?
Anything that was ripped off of a gas giant should be made up almost
exclusively of hydrogen, with a seasoning of other gasses.
2) He then has Venus careening about the inner system in a manner completely
inconsistent with the Newtonian laws of motion. It magically sheds vast
amounts of energy at just the right moment to allow it to settle into a
nearly-circular orbit.
3) During its trip, Venus manages to have two close encounters with Earth.
The first one stops the Earth's rotation, while the second one starts it
going again. Need I point out that such an event would produce mountains of
unmistakable evidence?
3a) This supposedly happened only a few thousand years ago, so as to account
for the Biblical account of the sun standing still in the sky for a day.
Need I point out that all macroscopic life on Earth would have been rendered
extinct by such an event?
3b) Oh, and somehow, Earth got re-started with exactly the same period of
rotation as before.
3c) And somehow both Earth and Mars retained their nearly-circular orbits.
Now, all of this comes from just a couple of chapters of one book. So far
as I can tell, the bogon flux remains at a similarly high level through the
rest of Velikovsky's work. Is anyone really surprised that it is thoroughly
discredited?
A few comments on the material that was originally quoted:
> With surface pressure 90 times and mass 75 times Earth's, the atmosphere
of
> Venus has thermal properties comparable to an ocean 3,000 feet deep.
> Penetration of solar energy is nowhere near sufficient to produce
> appreciable heating to any depth.
Sounds impressive, but what it really means is that the author doesn't know
anything about atmospheric science. What these numbers really show is that
it takes a long time for any change in solar energy output to have an effect
on the planet's surface temperature. That doesn't tell us anything at all
about what surface temperature to expect.
> Carbon dioxide, the major constituent of the
> atmosphere, is incapable of producing the postulated runaway
> on its own. It would require an additional component to "close" the
> critical 25 % transparency window that permits reradiation back into space
> at thermal wavelengths. Water vapor, the primary candidate, is
> conspicuously absent.
Why are we talking about 'candidates'? Anyone with a telescope can see that
Venus' atmosphere is in fact opaque to visible light. The last I heard, the
composition of Venus' atmosphere had been measured to a pretty high degree
of accuracy. Plug those numbers into a greenhouse simulation, and you get a
good agreement with the observed surface temperature value. So what problem
are we trying to explain?
> Probably the most damning for the
> greenhouse theory is the data from all of the US and Russian probes
> showing that the thermal gradient of the atmosphere is from base to
> cloud tops, i.e. the heat source is at the bottom, not outside.
Apparently, the author doesn't realize that this is exactly the result that
the greenhouse model predicts.
> According to the probe data, the emitted surface infrared flux is 40 times
> more than enters as sunlight.
Again, that's exactly what the greenhouse model would predict.
> Rigorous mathematical modeling by the thermodynamicist George R.
> Talbott showed that given an incandescent state 3,500 years ago as the
> recent-origin theory proposes, the cooling curve over that period yields a
> temperature today exactly as observed.
The kinds of energies Velikovsky throws around would be enough to melt the
surface of Venus to a depth of several hundred miles (we'll ignore the fact
that if it was ripped out of Jupiter's core it would have been completely
molten to start with). Bleeding that much heat off into space would take
several tens of millions of years, even without a thick atmosphere in the
way. The surface now should be thousands of degrees, not hundreds.
The rest of it is equally vacuous - it is the sort of thing that someone who
doesn't really grasp the underlying science would come up with. If anyone
wants more info on a specific point, let me know. On the whole, I think the
entire topic is not worth the time it takes to argue about it.
Billy Brown, MCSE+I
bbrown@conemsco.com
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