Haig, I don't know whether to laugh of cry ...
OK, I'll try to give
my understanding of the EU / PC view of Comets that I remember reading.
Comets approaching our variable star are charged bodies moving in the electric field of another larger charged body. As such the electromagnetic forces come into play and easily dominate gravity.
The charged comet causes a Langmuir Sheath to form around it with associated double layers. So the Coma and various tails grow along with the electrical stress.
Measuring density of such a body in such a field will produce errors IF the calculations used are "gravity only" in the assumption.
Think of measuring the density of a small electromagnet circling a much larger electromagnet by using the movement of the smaller IF it is highly elliptical (comets) and NOT simply circular or nearly circular. !
Most of today's physics, although developed, rely on relatively old ideas and formulas. The same goes for knowledge of plasma and electric currents as applied to astrophysics, and it was in fact several principles worked out by Kristian Birkeland and later Hannes Alfven that made much of the foundation for this.
Plasma Cosmology (or the Electric Universe) isn't refuting gravity as the dominating force in solid systems like our solar system. However, the bulk motion of an initial galactic dusty plasma is dominated by electromagnetism, and matter is later condensed into stars, where the orbital motion is preserved, whilst gravity takes over (briefly explained – see Anthony Peratt's papers).
Cometary Knots
Hence the errors in mainstream calculating the density of comets !
I'm sure not expecting you to agree with this just hope you can understand the thinking
How did it come to pass that the apparent hatred "the EU" core team has of science neutered your critical thinking skills?
Let's take an example that is several hundred years' old; the moons of Jupiter.
Galileo is the first to have reported seeing them, over 400 years' ago now. With even his really simple - and not very good, optically - telescope it is possible to make an estimate of the size - in arcseconds - of the size of Jupiter, and observe the motions of the four main moons. These are *quantitative* facts and data; you yourself can observe Jupiter and its four main moons, using very modest equipment that you can buy for merely a few hundred dollars (or make for yourself). And, with today's free apps etc, compile a pretty good dataset.
You can use this dataset to confirm that
Kepler's laws of planetary motion are a good fit to your dataset. If you are patient enough, you can do a modern day version of
Ole Rømer's measurement of the speed of light. With a small amount of high school mathematics (helped by the cornucopia of free apps) you yourself can confirm just how good a fit Kepler's laws are to much bigger datasets, of the positions of hundreds of solar system objects (including comets).
Best part of this? Two things: Kepler's laws are purely empirical/descriptive, and you need take no one's word for any of it, because you can do all of it yourself (even checking the veracity of math apps, if you so wish).
What would you learn?
Among other things: the estimated density of solar system objects - ones with more than one other in orbit around them (Sun, with planets; planets, with moons; etc) - is the same, no matter which 'in orbit' object you choose to use for the density estimate.
Also: by using Kepler's laws, you are not using any theory of gravity, plasma physics, or invisible pink unicorns pushing things around. True, it's not hard to show that Newton's universal law of gravitation produces Kepler's laws, but your work is independent of any such theory (for all you know, Birkeland had some proto-plasma law, from which you can derive Kepler's laws). In short, you are, to use DT's words, working entirely with DIRECT EVIDENCE.
Take away: density estimates, produced using Kepler's laws and DIRECT EVIDENCE, can be shown to be very consistent, for solar system objects big and small, on nearly circular orbits or highly elliptical ones, etc.
(Important note: I've - deliberately - left some important parts out, and some of those are critical; what do you think some of them are?)
Now to a point Tom Bridgman apparently never tires of making, what can you actually do? All the wonders of Newton's theory, General Relativity, plasma physics, etc may be interesting, but can you design a space probe, pack it with sensitive instruments, blast it into space, and have it arrive at 67P safely? Clearly the Rosetta mission team did just that.
Say whatever you like about the theories of gravity they used (or didn't use), the theories of plasma physics they used (or didn't use), you cannot gainsay the result.
Yet, based on what wrote - in the post of yours I'm quoting - that result is a miracle!
How did it come to pass that your reading of "the EU" led you to believe in miracles?
Expressed another way: why is "the EU" so sterile?
To close, why not take up Tom Bridgman's challenge? In
Electric Comets III: Mass vs. Charge.
