Standard Volcanic Surface
Necessary intensity of source for visibility: Therefore, for one photon to make it through a 1km thickness of Mozina plasma, we'd need about 10124 photons to be emitted by the source. Each photon carries 10-17 J of energy. So that's 10107 J of energy emitted by the source, which is vastly more energy than there is in the entire observable universe. In other words it is impossible for even one photon of 171A radiation to propagate through 1km of the Mozina plasma, no matter what the source.
I may well have made an error somewhere in there, so I invite critiques. Thanks to all - I learned from this.
On the opacity front, it goes not well for X-rays through Mozina's photosphere. While that adventure plays itself out, let us ask about another, little explored aspect of the Mozina Sun.
How is "a standard volcanic surface" ill-defined?
Easy: There is no such thing as a "standard volcanic surface" recognized in science. Each volcanic surface is peculiar to its specific environment. The terrestrial crust is dominated by silicates, whereas you propose some kind of surface dominated by iron. Even on Earth, volcanic terrain depends heavily of the nature of the extruded magma, dominated by silicates; cinder cones or shield volcanos develop very different kinds of terrain, very different kinds of surface; which is supposed to be the "standard" volcanic surface? You can't just throw out some vague reference to "standards" that are not "standard" except for you. Be specific. What are the chemical compositions of the surface and magma? What are the temperatures of the surface and magma?
Let us explore a bit further just what we are supposed to think that a "standard volcanic surface" is supposed to mean, since Mozina has provided us with no additional information on the subject. I assume, in the absence of any indication to the contrary, that "standard" must mean "Earth-like" or "terrestrial". Mozina uses the word
iron so much in reference to his surface that I have come to believe that he actually means
iron. However, neither of the two standard crusts on Earth (
oceanic and
continental) have much in the way of iron in them. Both are dominated by Silicon & Oxygen. See the
Abundances of Elements in Earth's Crust page from Hyperphysics, which simply averages the two together, and we see 46.6% Oxygen, 27.7% Silicon (by weight), and everything else in the descending single digits, with iron down around 5%. The
Wikipedia Earth page references a reliable geology text book and gives molecular abundances, for both oceanic & continental crusts (SiO
2 and AlO
3 dominate both, with FeO and Fe
2O
3 combining to around 6.3% continental and 8.5% oceanic (probably by weight, though the page is not explicit on that). These are in line with abundances I see in various reference sources of my own (e.g.,
Allen's Astrophysical Quantities, AIP Press, 4th edition 2000;
Mantle Convection in the Earth and Planets, Cambridge University Press, 2001).
There are physical & chemical differences between oceanic & continental crust, so as to render "standard" an ambiguous concept. But we can simply average the two together, as the differences are not all that huge for our purpose here, and just pretend that the combination of the two will represent our "standard volcanic surface", as Mozina likes to call it. First & foremost, we see that our standard surface has no more than 10% iron, and is anywhere from 30% to 50% SiO
2, with AlO
3 in second place. Already we see that the elemental composition of what appears to be the intended standard is vastly different from the only elemental composition we have been given for the "crust" of the sun, namely "iron". Hence, by what appears to be Mozina's own choice for "standard", the solar "volcanic surface" is quite non-standard. But we also notice that, with nice comfy temperatures of a few hundred Kelvins to roughly 1000 Kelvins, the standard crust is completely dominated by amorphous & crystalline molecular minerals, whereas on the sun, sporting a healthy 6000 Kelvins, the surface can have no molecules at all (the only regions of the sun cool enough for molecules to form are sunspot umbrae, around 3000 Kelvins).
Now, of course I am simply trying to guess what I think Mozina intends to mean by "standard", since he does not say. And considering his penchant for using Earth as a standard for gamma rays and magnetic reconnection, I simply assume that he means likewise for "standard volcanic surface". Since this raises some serious problems, we need the expert on "standard volcanic surfaces" himself, Mozina, to tell us what he thinks the volcanic surface of the sun looks like, in enough detail for us to explore this aspect of the "iron sun" as well.
