View source for Oliver K Manuel

{{Infobox scientist
| name = Oliver K. Manuel
| alt = Oliver K. Manuel
| birth_date = 1936
| nationality = American
| fields = Nuclear chemistry, cosmochemistry, nuclear geochemistry
| workplaces = University of Missouri–Rolla (Missouri University of Science and Technology)
| alma_mater = University of Arkansas
| doctoral_advisor = Paul Kazuo Kuroda
| known_for = "Iron sun" hypothesis; neutron repulsion as a stellar energy source; strange xenon in meteorites
}}

'''Oliver K Manuel''' (born 1936), usually cited as Oliver K. Manuel, is an American nuclear chemist and professor emeritus of chemistry at the University of Missouri–Rolla, now Missouri University of Science and Technology. He is known for isotopic studies of meteorites, lunar samples and the solar wind, and for a long-argued non-mainstream hypothesis that the Sun formed on the collapsed core of a supernova and is composed largely of iron rather than hydrogen.

==Biography==
Manuel began research on the origin of the solar system and its elements in 1960 as a student of the nuclear chemist Paul Kazuo Kuroda at the University of Arkansas, where he earned his doctorate. He subsequently joined the chemistry faculty of the University of Missouri–Rolla, where he spent the bulk of his career as a professor of nuclear chemistry and later became professor emeritus.

During the Apollo era he served as a NASA principal investigator, analysing noble gases in returned lunar samples. Among this early work was a study of the role of isotopic mass fractionation in producing noble gas anomalies in lunar fines returned by Apollo 15, presented at the Third Lunar Science Conference.

==Scientific contributions==
Manuel's experimental work centred on the isotopic composition of the noble gases — particularly xenon and krypton — and of tellurium in primitive meteorites, in planetary atmospheres, in lunar material, in the solar wind and in solar flares.

In 1972 Manuel and colleagues reported in ''Nature'' that the xenon in primitive meteorites is a mixture of "normal" xenon and an isotopically anomalous component that became known as "strange xenon", enriched in isotopes produced in supernova nucleosynthesis. In 1975 Manuel and his UMR colleague Dwarka Das Sabu reported that primordial helium in meteorites was trapped in the same sites as the strange xenon, and on this basis proposed that the solar system formed directly from the debris of a single nearby supernova rather than from a slowly collapsing interstellar cloud. Related isotopic evidence was published in 1979 in ''Nature'' as "Isotopes of tellurium, xenon and krypton in the Allende meteorite retain a record of nucleosynthesis", and Manuel returned to the wider question in a 1983 ''Meteoritics'' paper on solar abundances of the elements. He later pointed to the detection of strange xenon in Jupiter's atmosphere by the Galileo probe in 1996 as further support for his interpretation.

Extending this line of argument, Manuel maintained that the Sun formed on the collapsed core of that supernova and that iron, rather than hydrogen, is its most abundant element, with hydrogen concentrated at the surface. He presented this "iron sun" argument at the 199th meeting of the American Astronomical Society in Washington, D.C., in January 2002, together with Dwarka Das Sabu and the graduate student Cynthia Bolon. In a series of papers, including "Attraction and Repulsion of Nucleons: Sources of Stellar Energy" and "Neutron Repulsion Confirmed as Energy Source" in the ''Journal of Fusion Energy'' (with E. Miller and A. Katragada), he argued that repulsion between neutrons in a compact stellar core could release a larger fraction of nuclear rest mass than hydrogen fusion or fission, and proposed this as the Sun's principal energy source. He also argued that the Sun acts as a plasma diffuser that sorts atoms by mass, which he offered as an explanation for the hydrogen-rich composition observed at the photosphere.

These conclusions have not been accepted by mainstream astrophysics, which holds that the Sun is composed predominantly of hydrogen and helium and is powered by hydrogen fusion. When Manuel's 2002 presentation was reported in the press, solar physicists dismissed the iron-sun interpretation, and Manuel himself acknowledged having had little success in persuading most of his scientific colleagues over some four decades of advocacy.

==Selected publications==
* Manuel, O. K., Hennecke, E. W., and Sabu, D. D., "Xenon in carbonaceous chondrites", ''Nature'', 1972.
* Manuel, O. K. and Sabu, D. D., "Strange xenon, extinct superheavy elements and the solar neutrino puzzle", ''Science'', 1977.
* Manuel, O. K. and Sabu, D. D., "Isotopes of tellurium, xenon and krypton in the Allende meteorite retain a record of nucleosynthesis", ''Nature'' '''277''', 615–620, 1979.
* Manuel, O. K., "Solar abundances of the elements", ''Meteoritics'', 1983.
* Manuel, O. K., Miller, E., and Katragada, A., "Neutron repulsion confirmed as energy source", ''Journal of Fusion Energy'', 2001.
* Manuel, O., Kamat, S. A., and Mozina, M., "The Sun is a plasma diffuser that sorts atoms by mass", 2006.
* Manuel, O. K., "Fingerprints of a local supernova", 2009.

==External links==
* [https://scholarsmine.mst.edu/ Scholars' Mine, Missouri University of Science and Technology]

[[Category:Scientist|Manuel Oliver]]
[[Category:Worldwide List of Dissident Scientists]]