SETI bioastro: The Strange Case of the Iron Sol

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From: LARRY KLAES (ljk4@msn.com)
Date: Wed Apr 24 2002 - 08:32:32 PDT


THE STRANGE CASE OF THE IRON SUN

>From Discover Magazine, March 2002

http://www.discover.com/mar_02/feat_iron.html

An iconoclastic theory of the solar system's origin shows how science tests
its truisms.

By Solana Pyne

In the late 1960s, chemist Oliver Manuel made a small but staggering
discovery about meteorites. He noticed that the abundances of certain
elements in meteorites were distinctly different from those in the Earth and
much of the solar system. This observation spurred research showing that our
solar system probably formed from material generated in many different
stars. For Manuel, it also spawned a radical theory about the origins of our
solar system, which he has doggedly pursued for forty years. Nearly all
astronomers agree that the Sun and the rest of the planets formed from an
amorphous cloud of gas and dust 4.6 billion years ago. But Manuel argues,
based on his compositional data, that the solar system was created by a
dramatic stellar explosion--a supernova--and that the iron-encased remnant
of the progenitor star still sits at the center of the Sun.

Manuel fits a popular stereotype, the lone dissenter promoting a new idea
that flies in the face of the scientific establishment. In the real world,
some of these theories eventually have been proven right but vastly more
have been proven wrong. Manuel is under no illusions about the popularity of
his idea. "Ninety-nine percent of the field will tell you it's junk
science," he says. The evidence weighs in heavily against him. If he's
right, however, we need to completely rethink how planetary systems form.
Even if he's wrong, some scientists say, at least he has made people think.

Astrophysicists don't deny the validity of Manuel's original meteorite data.
"It was a good observation," says cosmochemist Frank Podosek of Washington
University. "This was something we hadn't observed before. It was a fruitful
thing to notice, but he picked it up and ran with it very much farther than
the basis could justify."

To support his theory, Manuel pieced together bits of information from
history, astronomy, biology and physics. He founded his theory on isotopes,
variants of an element that have different atomic weights but the same basic
chemical properties. On Earth, isotopes have consistent, well-known relative
abundances. Manuel cited unusual mixes of isotopes in meteorites and
possibly in the atmosphere of Jupiter as evidence that those objects formed
from the outer layers of a supernova, where such strange isotope ratios
would be the norm. The inner planets, made from rocky debris, formed from
heavy elements in the inner part of the supernova, he says, where more
familiar isotope concentrations prevailed. And the Sun, which Manuel argues
is iron-rich, formed around a neutron star, the collapsed remnant of the
exploded star. "This is not a news flash," he says. "This is my conclusion
from 42 years of measuring the abundance of isotopes."

Manuel's insistence both infuriates and amuses others in the field.
Scientists who know him talk about him in a tone that is both weary and
indulgent, as they would describe an eccentric relative. "I happen to like
Oliver," says Donald Burnett, professor of geochemistry at the California
Institute of Technology. "I don't agree with anything he says, but I find
him a colorful character."

There is one widely accepted element in Manuel's scenario. In the universe,
many elements heavier than iron are thought to have been forged in
supernovae. But the evidence increasingly seems to rule out Manuel's
supernova-genesis theory. At the start of the 20th century, many scientists
believed the Sun was made mostly of iron. Manuel cites the historical
support for an iron-rich Sun as evidence for his theory. "A high iron
content for the Sun is not revolutionary but is actually quite compatible
with the history of solar research," he says. But in 1925, astronomer
Cecelia Payne analyzed the light of our star and proposed that the Sun was
most likely a burning ball of hydrogen. By the late thirties, the case was
nearly settled. The surface of the Sun has been proven to be mostly
hydrogen, and many subsequent studies have led to extremely detailed models
of the hydrogen fusion reactions that power our star.

"We can make an explicit model of the Sun, putting its mass and brightness
into the computer, along with the laws of physics and that then produces
right amount of Sunshine and brightness," says Sallie Baliunas, an
astrophysicist at the Harvard-Smithsonian Center for Astrophysics. These
models also explain the various stages of stellar evolution that astronomers
can observe. And the principles of hydrogen fusion are well established,
both in the laboratory and in the detonations of hydrogen bombs. According
to theory and experiment, light hydrogen atoms in the Sun fuse together to
form helium atoms, releasing bursts of energy in the process. All of the
evidence points to our Sun being made primarily of hydrogen.

Manuel argues that the surface is made up mostly of hydrogen only because
elements in the Sun separate according to mass. Hydrogen, the lightest
element, floats to the surface, while heavier elements huddle below. But his
theory creates another problem: If the Sun isn't made of hydrogen, how does
it generate its energy? Fusing a heavy and stable element like iron consumes
more energy than it releases. In his theory, Manuel relies the neutron star
at the center to make up for energy lost when hydrogen is taken out of the
picture. The neutrons that make up the star have higher energy than free
neutrons, he says, so a neutron escaping from the star releases energy. The
free neutron then decays into a proton as it migrates toward the surface,
again releasing energy. The proton, which is a hydrogen atom minus an
electron, fuses to form helium and releases even more energy. He supposes
that some of the decayed neutrons stick around as protons and account for
the abundance of hydrogen on the surface of the Sun and in the solar wind.
Manuel's colleagues are skeptical about this elaborate and unproven
explanation.

Many scientists also find it improbable that our solar system could have
formed quickly from the debris of a supernova. They have only found one
system in which planets formed around a neutron star, and it looks nothing
like our solar system. On the other hand, astronomers have spotted
innumerable stars forming out of clouds of gas and dust and find strong
indications that planets are forming around these protostars.

Finally, there is persuasive evidence that our solar system contains the
remains of many different supernovae. Ironically, Manuel's own discovery
contributed to this understanding. Chemists have traced the strange isotopic
concentrations Manuel first observed to individual grains within meteorites.
The proportions of each isotope vary from grain to grain. If the solar
system formed from a single supernova, all the grains should have roughly
the same abundances of isotopes. Since they don't, most scientists view the
isotopes in a particular grain as a clue to its origin, and, hence, as
evidence that meteorites, and most other bodies in the solar system, are
made of heterogeneous material derived from many stars. That makes Manuel's
theory look less likely than ever. "Fifteen years ago, I would have kept a
question mark in my mind," said cosmochemist Roy Lewis, of the Fermi
Institute at the University of Chicago. "I would have said well he's almost
certainly wrong but by golly if he turns out to be right, won't that be
interesting."

Although most scientists don't believe Manuel's theory, they all acknowledge
that outlandish hypotheses have been proven correct in the past. It seems
especially unlikely in Manuel's case, however. In addition to citing the
contradictory evidence, many scientists also dismiss the iron-Sun theory on
the grounds of simplicity. Most observations of our solar system can be
explained by fairly common processes, so why evoke rare and complicated
explanations?

Still, some scientists see fringe theorists like Manuel as an asset, as they
make people reassess long-held theories. "Manuel is a little off the wall,"
Lewis says. "But science is filled with people a little off the wall. Our
great strength is to allow them to express their views." Manuel's views got
an airing again at the January meeting of the American Astronomical Society
meeting in Washington, DC, where once again they received little notice.

Meanwhile, Manuel continues to argue his theory with an air of implacable
certainty, believing that solar physics is on the verge of a revolution. He
talks as though scientists need only to come to their senses and reassess
the data. "I'm not trying to refute the professional careers of the
scientists whose shoulders I'm standing on," Manuel says. "My work depends
on their evidence. It's just a different interpretation."

----------------------------------------------------------------------------

----
RELATED WEB SITES:
See Oliver Manuel's site at http://www.umr.edu/~om/ Learn more about how the
planets of our solar system formed at http://explorezone.com/
space/planets.htm Find out about the elements formed in a supernova at
http://imagine.gsfc.nasa.gov/ docs/ask_astro/ answers/010125a.html Learn
about our Sun at http://www.seds.org/nineplanets/ nineplanets/sol.html

Copyright 2002 The Walt Disney Company. Back to Homepage.

============================ * LETTERS TO THE MODERATOR * ============================

(7) RE: THE STRANGE CASE OF THE IRON SUN

>From Oliver K. Manuel <om@umr.edu>

There is an article on Discovery Magazine's web site you may find interesting <http://www.discover.com/mar_02/feat_iron.html>. Sallie Baliunas of Harvard University, Frank Podosek of Washington University, Roy Lewis of the University of Chicago and the Genesis Project Principal Investigator - Don Burnett of Cal Tech - comment on the possibility of an iron-rich Sun.

They do NOT address observations that are unexplained by the standard model:

1. Meteorites trapped two types of xenon, Xe-X (highly enriched in r- and p-products) and "normal" xenon [Nature 240, 99-101 (1972)]. Xe-X was a major primordial xenon component at the birth of the solar system. The (excess Xe-136)/(excess-124) ratio is constant in meteorites.

2. Xe-X is closely linked with primordial helium and neon in diverse meteorites but the noble gas component with "normal" xenon is devoid of helium and neon [Science 195, 208-210 (1977); Icarus 41, 312-315 (1980); Meteoritics 15, 117-138 (1980)].

3. Normal xenon is found in troilite (FeS) of meteorites [Nature 299, 807-810 (1982); Geochem. J. 30, 17-30 (1996)], as well as in the rocky planets abounding with Fe and S - - Earth and Mars.

4. Xe-X is found in diamond inclusions of meteorites with abundant primordial helium and neon, trapped in a carbon matrix with normal C-13/C-12 isotope ratio [Nature 326, 160-162 (1987)].

5. The Galileo mission found evidence of Xe-X in the helium-rich atmosphere of Jupiter [J. Radioanal. Nucl. Chem. 238, 119-121 (1998)].

6. The Galileo mission found hydrogen and helium that could not be transformed into the anomalous hydrogen and helium isotope ratios of the solar wind by deuterium burning [Proceedings ACS Symposium, "Origin of Elements in the Solar System: Implications of Post-1957 Observations" (Kluwer Plenum Publishers, New York, NY, 2001) pp. 529-543].

7. Primordial helium and neon were plentiful where the outer planets formed, but light elements were absent where formed rocky planets formed. This primordial heterogeneity caused the paucity of light elements in inner planets [Comments Astrophysics 18, 335-345 (1997)].

8. The Apollo missions found mass fractionated "normal" xenon implanted in lunar samples by the solar wind, with light mass isotopes enriched by 3.5% per amu [Science 174, 1334-1336 (1971); Proc. Lunar Sci. Conf. 2, 1821-1856 (1972)].

9. When photospheric abundance is corrected for the fractionation seen across the nine isotopes of xenon, Fe and S are found to be abundant elements in the bulk Sun. Thus, the link of Fe and S with "normal" xenon extends to the Sun [Meteoritics 18, 209-222 (1983)].

10. The prevalence of solar wind implanted Li-6 and Be-10 in lunar soils is too high to be representative of the composition of the entire Sun [Nature 402, 270-273 (1999); Science 294, 352-354 (2001)].

11. Combined Pu-244/Xe-136 and U/Pb age dating indicates formation of the solar system began about 5 billion years ago, soon after a supernova explosion [Radiochimica Acta 77, 15-20 (1997)].

12. Decay products of short-lived nuclides and isotopic anomalies from nucleosynthesis are found in massive iron meteorites [Meteoritics & Planet. Sci., 33, A99 (1998); Nature 415, 881-883 (2002)], as well as in the tiny meteorite inclusions called "interstellar grains".

13. The abundance of one He-burning product, O-16, is characteristic of at least six different types of meteorites and planets [Earth Planet. Sci. Lett. 30, 10-18 (1976)].

Papers cited are from the University of Chicago, Physikalisches Institut-Bern, the University of Arkansas, CRPG-CNRS at Nancy, the University of California Berkeley, the University of Tokyo, Harvard University, and the University of Missouri-Rolla.

With kind regards,

Oliver K. Manuel Professor of Nuclear Chemistry University of Missouri Rolla, MO 65401 USA Phone: 573-341-4420 or -4344 Fax: 573-341-6033 E-mail: om@umr.edu http://www.umr.edu/~om/


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