Artificial radioactive element properties unknown	memory peg
	1953 Albert Ghiorso and co-workers, Berkeley, Calif., USA
	Enrico Fermi (1901-1954)

First prepared in 1953 by Albert Ghiorso, Stanley G. Thompson, Gary H. Higgins, Glenn T. Seaborg (from the Radiation Laboratory and Department of Chemistry of the University of California), Martin H. Studier, P.R. Fields, Sherman M. Fried, H. Diamond, J.F. Mech, G.L. Pyle, John R. Huizenga, A. Hirsch, W.M. Manning (from the Argonne National Laboratory), C.I. Browne, H. Louise Smith, and R.W. Spence (from the Los Alamos Scientific Laboratory) in first thermonuclear explosion of November 1952, together with Einsteinium. From the coral found on the spot of the explosion was it possible to extract only 200 atoms of element #100, and they identified it on so minute quantity of material (see also Einsteinium).

Both elements were named after eminent scientists, making these the first of a series named like this. The choice of Fermium for element #100 has proven to be prescient since it is the last element to be synthesized using neutron caption reactions, which were extensively studied by Fermi.

Enrico Fermi (1901-1954), Italian physicist, professor of theoretic physics in Rome, 1926-38. He was professor at Columbia University, New York, 1939-42, and from 1946 at Chicago. He proved the existence of new radioactive elements produced by bombardement with neutrons, and discovered nuclear reactions produced by low-energy neutrons. Nobel prize 1938. (Wordsworth).
An on-line biographies is available on the website of the Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois.

Stamp issued by USPS in Chicago on September 29, 2001 commemorating the 100th anniversary of Fermi's birth.

In 1953 researchers at the Nobel Institute in Stockholm prepared also element #100, they proposed the name Centurium (Ct), derived from the Latin Centum = hundred. This name appeared also in non-specialist magazines of the year 1950/51 (Cf. Einsteinium). Because of the military secrets, the American discovery was not made public at that time. After their publication in 1955 it became clear Fermium has the priority

Further reading:

• Mary Elvira Weeks, Discovery of the Elements, comp. rev. by Heny M. Leicester (Easton, Pa.: Journal of Chemical Education, 1968), pp. 850-851.
• Earl K. Hyde & Glenn T. Seaborg, Transurane : Teil A 1, I: Die Elemente. Gmelins Handbuch der anorganische Chemie, Ergänzungswerk zur 8. Aufl.; Band 7a. Weinheim/Bergstrasse: Chemie, 1973.
• Glenn T. Seaborg, Transuranium elements: A Half Century. Remarks at ACS Symposium to Commemorate the 50th Anniversary of Transuranium Elements, Washington D.C., August 27, 1990. (PDF-file available on-line).
• Glenn T. Seaborg, Early History of LBNL, A transcript of the lecture on the 65th Anniversary of Lawrence Berkeley National Laboratory, August 26, 1996 (on-line).
• A. Ghiorso, S.G. Thompson, G.H. Higgins, G.T. Seaborg, M.H. Studier, P.R. Fields, H. Diamond, J.F. Mech, G.L. Pyle, J.R. Huizenga, A. Hirsch, W.M. Manning, C.I. Browne, H.L. Smith, and R.W. Spence, "New Elements Einsteinium and Fermium, Atomic Numbers 99 and 100". Phys. Rev. 99 (1955), 1048.