Marvin Herndon, pictured at left, has discovered that only three
processes, operant during the formation of the Solar System, are
responsible for the diversity of matter in the Solar System and are
directly responsible for planetary internal-structures, including
planetocentric nuclear fission reactors, and for dynamical processes,
including and especially, geodynamics. These processes are: (i)
Low-pressure, low-temperature condensation from solar matter in the
remote reaches of the Solar System or in the interstellar medium, which
leads to oxygen-rich condensates; (ii) High-pressure,
high-temperature condensation from solar matter associated with
planetary-formation by raining out from the interiors of giant-gaseous
protoplanets, which leads to oxygen-starved planetary interiors, and; (iii)
Stripping of the primordial volatile components from the inner portion
of the Solar System by super-intense solar wind associated with T-Tauri
phase mass-ejections, presumably during the thermonuclear ignition of
the Sun .
constancy in isotopic compositions of most of the elements of the Earth,
the Moon, and the meteorites indicates formation from primordial matter
of common origin. Primordial elemental composition is yet evident to a
great extent in the photosphere of the Sun and, for the less volatile,
rock-forming elements, in chondrite meteorites. There is, however, a
fundamental degree of complexity which has posed an impediment to
understanding for more than half a century: Instead of just one type of
chondrite there are three, with each type characterized by its own
strikingly unique state of oxidation. Understanding the nature of the
processes that yielded those three distinct types of matter from one
common progenitor forms the basis for understanding much about planetary
formation, their compositions, and the processes they manifest,
including and especially magnetic field production.
five major elements [Fe, Mg, Si, O, and S] comprise at least 95% of the
mass of each chondrite and, by implication, each of the terrestrial
planets, and act as a buffer assemblage. Minor and trace elements are
slaves to that buffer system and are insufficiently abundant to alter
oxidation state. For decades, the abundances of major rock-forming
elements (Ei) in chondrites have been expressed in the
literature as ratios, usually relative to silicon (Ei/Si)
and occasionally relative to magnesium (Ei/Mg).
By expressing Fe-Mg-Si elemental abundances as molar (atom) ratios
relative to iron (Ei/Fe),
Herndon  discovered a fundamental relationship bearing on the genesis
of chondrite matter, which has implications on the nature of planetary
processes in our Solar System; image at right. The relationship obtained admits the
possibility of ordinary chondrites having been derived from mixtures of
two components, representative of the other two types of
chondrite-matter. One component appears to be a relatively
undifferentiated carbonaceous-chondrite-like primitive component, while
the other, a partially differentiated enstatite-chondrite-like planetary
component, appears to have originated from a large reservoir. Herndon
suggested the partially-differentiated planetary component might be
comprised of matter stripped from the protoplanet of Mercury, presumably
by the T-Tauri solar wind during thermonuclear ignition of the Sun .
In other words, ordinary chondrite matter is not a primary building
material for planets, although it might contribute a veneer to the
terrestrial planets, especially to Mars.
observations demonstrate conclusively that T-Tauri-type outbursts can be
of sufficient magnitude to scour the terrestrial-planet region of our
Solar System. The Hubble Space Telescope image at left shows just such
an outburst of the binary XZ-Tauri, taken in 2000. The white crescent
embedded in the plume marks the leading edge of that outburst five years
before. In five years the leading edge of the plume progressed a
distance equivalent to 130 times the distance from our Sun to Earth.
confusion has arisen from decades of making computational models based
upon the erroneous assumptions that the mineral assemblage
characteristic of ordinary chondrites formed in equilibrium in an
atmosphere of solar composition at very low pressures, ca. 10-4
bars, and that
ordinary-chondrite-like matter comprises planetary interiors.
Herndon and Suess  have shown that ordinary chondrite formation
necessitates, not an atmosphere of solar composition, but instead an
atmosphere depleted in hydrogen by a factor of about 1000. Subsequently,
Herndon  showed the impossibility of ordinary chondrite-matter being
in equilibrium with a gas of solar composition, and showed as well the
necessity of some oxygen depletion relative to solar matter. Moreover,
the ordinary chondrites appear, not primary, but rather as a secondary
mixture, leaving only two types of primary matter, the oxygen-rich
carbonaceous chondrite-type matter and the oxygen-starved enstatite
chondrite-type matter .
As early as 1940, scientists, including the renowned
Harvard geophysicist Francis Birch, built geophysics upon the premise
that the Earth is like an ordinary chondrite, one of the most common
types of meteorites observed impacting Earth, while totally ignoring
another, albeit less abundant type, called enstatite chondrites. As
Herndon  discovered in 1980, if the Earth is indeed like a chondrite
meteorite as widely believed for good reasons, Earth is like an
enstatite chondrite, not an ordinary chondrite. Imagine melting a
chondrite in a gravitational field. At elevated temperatures, the iron
metal and iron sulfide components will alloy together, forming a dense
liquid that will settle beneath the silicates like steel on a
steel-hearth. The Earth is like a spherical steel-hearth with a fluid
iron-alloy core surrounded by a silicate mantle.
Earth’s core comprises about 32.5% of the planets mass. Only the
enstatite chondrites (filled circles), not the ordinary chondrites (open
circles), have the sufficiently high proportion of iron-alloy that is
observed for the core of the Earth, as shown in at left. Moreover,
components of the interior of the Earth, shown at right, can be
identified with corresponding components of an enstatite chondrite
meteorite: (1) The inner core being nickel silicide; (2) Earth-core
precipitates CaS and MgS at the core-mantle boundary; (3) The lower
mantle consisting of essentially FeO-free MgSiO3; and, (4)
The boundary between the upper and lower mantle being a compositional
boundary with the matter below that boundary, the endo-Earth, being like
an enstatite chondrite [5-8]. Those discoveries and insights led to a
fundamentally different view of Earth formation, dynamics, energy
production, and energy transport process [1, 9, 10].
In the 1940s and 1950s, the idea was generally discussed
about planets “raining out” from inside of giant gaseous protoplanets
with hydrogen gas pressures on the order of 102-103
bars [11-14]. But, in the early 1960s, scientists instead began thinking
of primordial matter, not forming dense protoplanets, but rather spread
out into a very low-density “solar nebula” with hydrogen gas pressures
on the order of 10-4 to 10-5
bars. The idea of low-density planetary formation, often referred to as
the “standard model”, envisioned that dust would condense at fairly low
temperatures, and then would gather into progressively larger grains,
and become rocks, then planetesimals, and ultimately planets [28, 29].
two ideas about planetary formation embody fundamentally different
condensation processes which are the underlying cause for the two unique
primary types of chondritic matter. The immediate implication is that
both processes were operant during the formation of the Solar System.
The relative extent and region of each process can be ascertained to
some certitude from thermodynamic considerations together with planetary
data. Even within present limitations, a consistent picture emerges that
is quite unlike the so-called “standard model of solar system formation”
thermodynamic considerations it is possible to make some generalizations
related to the condensation process in an atmosphere of solar
composition. At the foundation, there are two dominant considerations,
one essentially independent of pressure and one a strong function of
pressure, which together are responsible for formation of the two
primary types of Solar System matter.
In an atmosphere of solar composition, oxygen fugacity is
dominated by the gas-phase reaction H2
+ ˝O2 = H2O
which is a function of temperature, but is essentially independent of
pressure over a wide range of pressures where ideal gas behavior is
approached. Oxygen fugacity controls the condensate state of oxidation
at a particular temperature. At high temperatures the state of oxidation
is extremely reducing, while at low temperatures it is quite oxidizing.
The state of oxidation of the condensate ultimately becomes fixed at the
temperature at which reaction with the gas phase ceases and/or
equilibrium is frozen-in by the separation of gases from the condensate.
Condensation of an element or compound is expected to
occur when its partial pressure in the gas becomes greater than its
vapor pressure. Generally, at high pressures in solar matter,
condensation is expected to commence at high temperatures, while at low
pressures, such as 10-4 to
10-5 bar, condensation is
expected to progress at relatively low temperatures at a fairly
oxidizing range of oxygen fugacity. At low temperatures, all of the
major elements in the condensate may be expected to be oxidized because
of the great abundance of oxygen in solar matter relative to the other
major condensable elements . Beyond these generalizations, in this
low-pressure regime, precise theoretical predictions of specific
condensate compounds may be limited by kinetic nucleation dynamics and
by gas-grain temperature differences arising because of the different
mechanisms by which gases and condensate lose heat.
the thousands of known chondrites, only a few, like the famous Orgueil
carbonaceous chondrite, have a state of oxidation and mineral components
with characteristics similar to those expected as a condensate from
solar matter at low pressures. Essentially all of the major elements in
these few chondrites are oxidized, including sulfur.
idea of planetary formation from a diffuse solar nebula, with hydrogen
pressures on the order of 10-4
to 10-5 bar, envisioned that
dust would condense at fairly low temperatures, and then would gather
into progressively larger grains, and become rocks, then planetesimals,
and ultimately planets. In the main, that picturesque idea leads to the
contradiction of the terrestrial planets having insufficiently massive
cores, because the condensate would be far too oxidized for a high
proportion of iron metal to exist. But as evidenced by Orgueil and
similar meteorites, such low-temperature, low-pressure condensation did
in fact occur, perhaps only in the evolution of matter of the outer
regions of the Solar System or in interstellar space, and thus may
contribute to terrestrial planet formation only as a component of
late-addition planetary veneer.
the basis of thermodynamic considerations, Eucken suggested in 1944
core-formation in the Earth as a volatility-controlled consequence of
successive condensation from solar matter in the central region of a
hot, gaseous protoplanet with molten iron metal first raining out at the
center . Except for a few investigations initiated in the 1950s and
early 1960s [12, 13, 15, 16], that idea languished when interest was
diverted to Cameron’s low-pressure solar nebula models .
the basis of thermodynamic considerations, Herndon and Suess  showed
at the high-temperatures for condensation at high-pressures, solar
matter is sufficiently reducing, i.e., it has a sufficiently low
oxygen fugacity, for the stability of some enstatite chondrite minerals
as shown in the figure at left, where the phase boundary between iron
gas and liquid iron metal is a function of temperature and pressure in
an atmosphere of solar composition, calculated from thermodynamic data,
but the oxygen fugacity values are independent of pressure However,
formation of enstatite-chondrite-like condensate would necessitate
thermodynamic equilibrium being frozen-in at near-formation
temperatures. At present, there is no adequate published theoretical
treatment of solar-matter condensation from near the triple-point. But
from thermodynamic and metallurgical considerations, some
generalizations can be made. At the high temperatures at which
condensation is possible at high pressures, nearly everything reacts
with everything else and nearly everything dissolves in everything else.
At such pressures, molten iron, together with the elements that dissolve
in it, is the most refractory condensate.
Chondrite elemental abundances are nearly identical to solar element
abundances for the relatively non-volatile rock-forming elements. If
Earth is like a chondrite element, as widely believed, then adding to
Earth’s mass the corresponding proportion of gaseous elements and those
elements which form highly volatile compounds, calculated from solar
abundances, yields an estimate of the mass of protoplanetary-Earth being
in the range 275-305mE, not very
different from the mass of Jupiter, 318mE.
The formation of early-phase close-in gas giants
in our own planetary system is consistent with observations and
implications of near-to-star giant gaseous planets in other planetary
systems [19-21]. It is thus reasonable to expect that the giant planets
possess interior rock-plus-alloy kernels of enstatite-chondritic-like
matter as they each possess internally generated magnetic fields .
the absence of evidence to the contrary, the observed
enstatite-chondritic composition of the terrestrial planets, as
indicated by their massive cores, permits the deduction that these
planets formed by raining out from the central regions of hot, gaseous
protoplanets . With the possible exception of Mercury, the outer
veneer of the terrestrial planets may contain other components derived
from carbonaceous-chondrite-like matter and from ordinary-chondrite-like
matter. Mars, for example, may have an extensive outer veneer, while for
Earth, it is ≤18% by mass. Satellites may possess an internal kernel of
enstatite-chondritic-matter. The particular importance of
enstatite-chondritic-matter derives from the highly reduced state of
oxidation during formation, which forced certain oxyphile elements, such
as uranium, into the alloy portion, rather than into the silicate,
resulting in the possibility of georeactor-like magnetic field
generation in planets of our Solar System .
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