• Physicist Henry Gwyn Jeffreys Moseley, 1887
• Chemist Glenn Theodore Seaborg, 1912

Henry Gwyn Jeffreys Moseley (23 November 1887 – 10 August 1915) was an English physicist. Moseley's outstanding contribution to the science of physics was the justification from physical laws of the previous empirical and chemical concept of the atomic number. This stemmed from his development of Moseley's law in X-ray spectra. Moseley's Law justified many concepts in chemistry by sorting the chemical elements of the periodic table of the elements in a quite logical order based on their physics.

Moseley's law advanced atomic physics by providing the first experimental evidence in favor of Niels Bohr's theory, aside from the hydrogen atom spectrum which the Bohr theory was designed to reproduce. That theory refined Ernest Rutherford's and Antonius Van den Broek's model, which proposed that the atom contains in its nucleus a number of positive nuclear charges that is equal to its (atomic) number in the periodic table. This remains the accepted model today.

When World War I broke out in Western Europe, Moseley left his research work at the University of Oxford behind to volunteer for the Royal Engineers of the British Army. Moseley was assigned to the force of British Empire soldiers that invaded the region of Gallipoli, Turkey, in April 1915, as a telecommunications officer. Moseley was shot and killed during the Battle of Gallipoli on August 10, 1915, at the age of 27. Some prominent authors have speculated that Moseley could have been awarded the Nobel Prize in Physics in 1916, had he not died in the service of the British Army.

Henry Gwyn Jeffreys Moseley was born in Weymouth, Dorset, on the south coast of England in 1887. His father Henry Nottidge Moseley (1844 – 91), who died when Henry Moseley was quite young, was a biologist and also a professor of anatomy and physiology at the University of Oxford, who had been a member of the Challenger Expedition. Moseley's mother was Amabel Gwyn Jeffreys Moseley, who was the daughter of the biologist and conchologist John Gwyn Jeffreys.

Henry Moseley had been a very promising schoolboy at Summer Fields School (where one of the four 'leagues' is named after him), and he was awarded a King's scholarship to attend Eton College. In 1906, Moseley entered the Trinity College of the University of Oxford, where he earned his bachelor's degree. Immediately after graduation from Oxford in 1910, Moseley entered the graduate school at the University of Manchester to study and work under the supervision of professors such as Sir Ernest Rutherford. During Moseley's first year at Manchester, he had a teaching load as a graduate teaching assistant, but following that first year, he was reassigned from his teaching duties to work as a graduate research assistant.

In 1913, Moseley observed and measured the X-ray spectra of various chemical elements (mostly metals) that were found by the method of diffraction through crystals. This was a pioneering use of the method of X-ray spectroscopy in physics, using Bragg's diffraction law to determine the X-ray wavelengths. Moseley discovered a systematic mathematical relationship between the wavelengths of the X-rays produced and the atomic numbers of the metals that were used as the targets in X-ray tubes. This has become known as Moseley's law.

Before Moseley's discovery, the atomic numbers (or elemental number) of an element had been thought of as a semi - arbitrary sequential number, based on the sequence of atomic masses, but modified somewhat where chemists found this to be desirable, such as by the great Russian chemist, Dimitri Ivanovich Mendeleev. In his invention of the Periodic Table of the Elements, Mendeleev had interchanged the orders of a few pairs of elements in order to put them in more appropriate places in this table of the elements. For example, the metals cobalt and nickel had been assigned the atomic numbers 27 and 28, respectively, based on their known chemical and physical properties, even though they have nearly the same atomic masses. In fact, the atomic mass of cobalt is slightly larger than that of nickel, which would have placed them in backwards order if they had been placed in the Periodic Table blindly according to atomic mass. Moseley's experiments in X-ray spectroscopy showed directly from their physics that cobalt and nickel have the different atomic numbers, 27 and 28, and that they are placed in the Periodic Table correctly by Moseley's objective measurements of their atomic numbers. Hence, Moseley's discovery demonstrated that the atomic numbers of elements are not just rather arbitrary numbers based on chemistry and the intuition of chemists, but rather, they have a firm experimental basis from the physics of their X-ray spectra.

In addition, Moseley showed that there were gaps in the atomic number sequence at numbers 43, 61, 72, and 75. These spaces are now known, respectively, to be the places of the radioactive synthetic elements technetium and promethium, and also the last two quite rare naturally occurring stable elements hafnium (discovered 1923) and rhenium (discovered 1925). Nothing about these four elements was known of in Moseley's lifetime, not even their very existence. Based on the intuition of a very experienced chemist, Dimitri Mendeleev had predicted the existence of a missing element in the Periodic Table, which was later found to be filled by technetium, and Bohuslav Brauner had predicted the existence of another missing element in this Table, which was later found to be filled by promethium. Henry Moseley's experiments confirmed these predictions, by showing exactly what the missing atomic numbers were, 43 and 61. In addition, Moseley predicted the two more undiscovered elements, those with the atomic numbers 72 and 75, and he gave very strong evidence that there were no other gaps in the Periodic Table between the elements aluminium (atomic number 13) and gold (atomic number 79).

This latter question about the possibility of more undiscovered ("missing") elements had been a standing problem among the chemists of the world, particularly given the existence of the large family of the lanthanide series of rare earth elements. Moseley was able to demonstrate that these lanthanide elements, i.e., lanthanum through lutetium, must have exactly 15 members - no more and no less. The number of elements in the lanthanides had been a question that was very far from being settled by the chemists of the early 20th Century. They could not yet produce pure samples of all the rare earth elements, even in the form of their salts, and in some cases they were unable to distinguish between mixtures of two very similar (adjacent) rare earth elements from the nearby pure metals in the Periodic Table. For example, there was a so-called "element" that was even given the chemical name of "didymium". "Didymium" was found some years later to be simply a mixture of two genuine rare earth elements, and these were given the names neodymium and praseodymium, meaning "new twin" and "green twin". Also, the method of separating the rare earth elements by the method of ion exchange had not been invented yet in Moseley's time.

Moseley's method in early X-ray spectroscopy was able to sort out the above chemical problems promptly, some of which had occupied chemists for a number of years. Moseley also predicted the existence of element 61, a lanthanide whose existence was previously unsuspected. Quite a few years later, this element 61 was created artificially in nuclear reactors and was named promethium.

Sometime in the first half of 1914, Moseley resigned from his position at Manchester, with plans to return to Oxford and continue his physics research there. However, World War I broke out in August 1914, and Moseley turned down this job offer to enlist in the Royal Engineers of the British Army instead. Moseley served as a technical officer in communications during the Battle of Gallipoli, in Turkey, beginning in April 1915, where he was killed in action on August 10, 1915. Moseley was shot through the head by a Turkish sniper while in the act of telephoning a military order. Isaac Asimov once wrote, "In view of what he [Moseley] might still have accomplished ... his death might well have been the most costly single death of the War to mankind generally." Because of Moseley's death in World War I, the British government instituted a policy of no longer allowing its prominent and promising scientists to enlist for combat duty in the armed forces of the Crown.

Isaac Asimov has also speculated that in the event that he had not been killed while in the service of the British Empire, Moseley might very well have been awarded the Nobel Prize in Physics in 1916, which was not awarded to anyone that year (along with the prize for Chemistry). Additional credence is given to this by noting who won the Nobel Prize in Physics in the two previous years, 1914 and 1915, and in the following year, 1917. In 1914, Max von Laue of Germany won the Nobel Prize in Physics for his discovery of the diffraction of X-rays by crystals, which was a crucial step towards the invention of X-ray spectroscopy. Then, in 1915, William Henry Bragg and William Lawrence Bragg, a British father - son pair, shared this Nobel Prize for their discoveries in the reverse problem - determining the structure of crystals using X-rays. Next, Moseley used the diffraction of X-rays by known crystals in measuring the X-ray spectra of metals. This was the first use of X-ray spectroscopy and also one more step towards the creation of X-ray crystallography. In addition, Moseley's methods and analyses made the huge step of placing the concept of atomic number on a firm foundation based in physics. On top of all of this, Charles Barkla of Great Britain was awarded this Nobel Prize in 1917 for his experimental work in using X-ray spectroscopy in discovering the characteristic X-ray frequencies emitted by the various elements, especially the metals. Moseley's discoveries were thus of the same scope as those of his peers, and in addition, Moseley made the larger step of demonstrating the actual foundation of atomic numbers.

Only twenty - seven years old at his death, Moseley could in many scientists' opinions have contributed a lot to the knowledge of atomic structure had he survived. As Niels Bohr once said in 1962, "You see actually the Rutherford work [the nuclear atom] was not taken seriously. We cannot understand today, but it was not taken seriously at all. There was no mention of it any place. The great change came from Moseley."

Before Moseley and his law, atomic numbers had been thought of as a semi - arbitrary ordering number, vaguely increasing with atomic weight but not strictly defined by it. Moseley's discovery showed that atomic numbers were not arbitrarily assigned, but rather, they have a strong physical basis. Moseley redefined the idea of atomic numbers from its previous status as an ad hoc numerical tag to help sorting the elements, in particular in the Periodic Table, into a real and objective whole number quantity that was experimentally measurable. Furthermore, as noted by Bohr, Moseley's law provided a reasonably complete experimental set of data that supported the (new from 1911) conception by Ernest Rutherford and Antonius Van den Broek of the atom, with a positively charged nucleus surrounded by negatively charged electrons in which the atomic number is understood to be the exact physical number of positive charges (later discovered and called protons) in the central atomic nuclei of the elements. Moseley mentioned the two scientists above in his research paper, but he did not actually mention Bohr, who was rather new on the scene then. Simple modification of Rydberg's and Bohr's formulas were found to give theoretical justification for Moseley's empirically derived law for determining atomic numbers.

X-ray spectrometers are the foundation stones of X-ray crystallography. The X-ray spectrometers as Moseley knew them worked as follows. A glass - bulb electron tube was used, similar to that held by Moseley in the photo at the top of this article. Inside the evacuated tube, electrons were fired at a metallic substance (i.e., a sample of pure element in Moseley's work), causing the ionization of electrons from the inner electron shells of the element. The rebound of electrons into these holes in the inner shells next causes the emission of X-rays photons that were led out of the tube in a semi - beam, through an opening in the external X-ray shielding. These are next diffracted by a standardized salt crystal, with angular results read out as photographic lines by the exposure of an X-ray film fixed at the outside the vacuum tube at a known distance. Application of Bragg's law (after some initial guesswork of the mean distances between atoms in the metallic crystal, based on its density) next allowed the wavelength of the emitted rays to be calculated.

Moseley participated in the design and development of early X-ray spectrometry equipment, learning some techniques from William Henry Bragg and William Lawrence Bragg at the University of Leeds, and developing others himself. Many of the techniques of X-ray spectroscopy were inspired by the methods that are used with visible light spectroscopes and spectrograms, by substituting crystals, ionization chambers, and photographic plates for their analogs in light spectroscopy. In some cases, Moseley found it necessary to modify his equipment to detect particularly soft [lower frequency] X-rays that could not penetrate either air or paper, by working with his instruments in a vacuum chamber, and in the dark.

Glenn Theodore Seaborg (Swedish: Glenn Teodor Sjöberg; April 19, 1912 – February 25, 1999) was an American scientist who won the 1951 Nobel Prize in Chemistry for "discoveries in the chemistry of the transuranium elements", contributed to the discovery and isolation of ten elements, and developed the actinide concept, which led to the current arrangement of the actinoid series in the periodic table of the elements. He spent most of his career as an educator and research scientist at the University of California, Berkeley where he became the second Chancellor in its history and served as a University Professor. Seaborg advised ten presidents from Harry S. Truman to Bill Clinton on nuclear policy and was the chairman of the United States Atomic Energy Commission from 1961 to 1971 where he pushed for commercial nuclear energy and peaceful applications of nuclear science. Throughout his career, Seaborg worked for arms control. He was signator to the Franck Report and contributed to the achievement of the Limited Test Ban Treaty, the Nuclear Non - Proliferation Treaty, and the Comprehensive Test Ban Treaty. Seaborg was a well known advocate of science education and federal funding for pure research. He was a key contributor to the report "A Nation at Risk" as a member of President Reagan's National Commission on Excellence in Education and was the principal author of the Seaborg Report on academic science issued in the closing days of the Eisenhower administration.

Seaborg was the principal or co-discoverer of ten elements: plutonium, americium, curium, berkelium, californium, einsteinium, fermium, mendelevium, nobelium and element 106, which was named seaborgium in his honor while he was still living. He also developed more than 100 atomic isotopes, and is credited with important contributions to the chemistry of plutonium, originally as part of the Manhattan Project where he developed the extraction process used to isolate the plutonium fuel for the second atomic bomb. Early in his career, Seaborg was a pioneer in nuclear medicine and developed numerous isotopes of elements with important applications in the diagnosis and treatment of diseases, most notably iodine - 131, which is used in the treatment of thyroid disease. In addition to his theoretical work in the development of the actinide concept which placed the actinide series beneath the lanthanide series on the periodic table, Seaborg proposed the placement of super - heavy elements in the transactinide and superactinide series. After sharing the 1951 Nobel Prize in Chemistry with Edwin McMillan, he received approximately 50 honorary doctorates and numerous other awards and honors. The list of things named after Seaborg ranges from his atomic element to an asteroid. Seaborg was a prolific author, penning more than 50 books and 500 journal articles, often in collaboration with others. He received so many awards and honors that he was once listed in the Guinness Book of World Records as the person with the longest entry in Who's Who in America.

Of Swedish, distant German and Belgian (Flemish and Walloon) ancestry, Seaborg was born in Ishpeming, Michigan, the son of Herman Theodore (Ted) and Selma Olivia Erickson Seaborg. He had one sister, Jeanette. When Glenn Seaborg was a boy, the family moved to the Seaborg Home in a subdivision called Home Gardens, that was later annexed to the City of South Gate, California, a suburb of Los Angeles.

He kept a daily journal from 1927 until he suffered a stroke in 1998. As a youth, Seaborg was both a devoted sports fan and an avid movie buff. His mother encouraged him to become a book keeper as she felt his literary interests were impractical. He did not take an interest in science until his junior year when he was inspired by Dwight Logan Reid, a chemistry and physics teacher at David Starr Jordan High School in Watts.

He graduated from Jordan in 1929 at the top of his class and received a bachelor's degree in chemistry at the University of California, Los Angeles, in 1933. While at UCLA, he was invited by his German professor to meet Albert Einstein, an experience that had a profound impact on Seaborg and served as a model of graciousness for his encounters with aspiring students in later years. Seaborg worked his way through school as a stevedore (longshoreman), fruit packer and laboratory assistant.

Seaborg took his Ph.D. in chemistry at the University of California, Berkeley, in 1937 with a doctoral thesis on the inelastic scattering of neutrons in which he coined the term "nuclear spallation". He was a member of the professional chemistry fraternity Alpha Chi Sigma. As a graduate student in the 1930s Seaborg performed wet chemistry research for his advisor Gilbert Newton Lewis and published three papers with him on the theory of acids and bases. Seaborg then studied thoroughly the text Applied Radiochemistry by Otto Hahn, of the Kaiser Wilhelm Institute for Chemistry in Berlin and it had a major impact on his developing interests as a research scientist. For several years, Seaborg conducted important research in artificial radioactivity using the Lawrence cyclotron at UC Berkeley. He was excited to learn from others that nuclear fission was possible — but also chagrined, as his own research might have led him to the same discovery.

Seaborg also became expert in dealing with noted Berkeley physicist Robert Oppenheimer. Oppenheimer had a daunting reputation, and often answered a junior man's question before it had even been stated. Often the question answered was more profound than the one asked, but of little practical help. Seaborg learned to state his questions to Oppenheimer quickly and succinctly.

Seaborg remained at the University of California, Berkeley, for post - doctoral research. He followed Frederick Soddy's work investigating isotopes and contributed to the discovery of more than 100 isotopes of elements. Using one of Lawrence's advanced cyclotrons, John Livingood, Fred Fairbrother, and Seaborg created a new isotope of iron, iron - 59 (Fe-59) in 1937. Iron - 59 was useful in the studies of the hemoglobin in human blood. In 1938, Livingood and Seaborg collaborated (as they did for five years) to create an important isotope of iodine, iodine - 131 (I-131) which is still used to treat thyroid disease. (Many years later, it was credited with prolonging the life of Seaborg's mother.) As a result of these and other contributions, Seaborg is regarded as a pioneer in nuclear medicine and is one of its most prolific discoverers of isotopes.

In 1939 he became an instructor in chemistry at Berkeley, was promoted to assistant professor in 1941 and professor in 1945.

UC Berkeley physicist Edwin McMillan had led a team that discovered element 93, neptunium in 1940. In November 1940, McMillan was persuaded to leave Berkeley temporarily to assist with urgent research in radar technology. Since Seaborg and his colleagues had perfected McMillan's oxidation - reduction technique for isolating neptunium, he asked McMillan for permission to continue the research and search for element 94. McMillan agreed to the collaboration. Seaborg first reported alpha decay proportionate to only a fraction of the element 93 under observation. The first hypothesis for this alpha particle accumulation was contamination by uranium, which produces alpha decay particles; analysis of alpha decay particles ruled this out. Seaborg then postulated that a distinct alpha producing element was being formed from element 93. In February 1941, Seaborg and his collaborators produced plutonium - 239 through the bombardment of uranium. This experimental achievement changed the course of human history in ways more profound than they could have ever imagined: the production of plutonium - 239 was successful. In their experiments bombarding uranium with deuterons, they observed the creation of neptunium, element 93. But it then underwent beta decay, forming a new element, plutonium, with 94 protons. Plutonium is fairly stable, but undergoes alpha decay, which explained the presence of alpha particles coming from neptunium. Thus, on March 28, 1941, Dr. Seaborg, physicist Emilio Segrè and Berkeley chemist Joseph W. Kennedy were able to show that plutonium (then known only as element 94²³⁹) underwent fission with slow neutrons, an important distinction that was crucial to the decisions made in directing Manhattan Project research. Room 307 of Gilman Hall on the campus at the University of California, Berkeley, where Seaborg did his work, has since been declared a U.S. National Historic Landmark.

In addition to plutonium, he is credited as a lead discoverer of americium, curium, and berkelium, and as a co-discoverer of californium, einsteinium, fermium, mendelevium, nobelium and seaborgium. He shared the Nobel Prize in Chemistry in 1951 with Edwin McMillan for "their discoveries in the chemistry of the first transuranium elements." He obtained patents on americium and curium, which were developed in 1944 in Chicago at the wartime metallurgical laboratory during the Manhattan project. His research contributions to all of the other elements were conducted at the University of California, Berkeley.

On April 19, 1942, Seaborg reached Chicago, and joined the chemistry group at the Metallurgical Laboratory of the Manhattan Project at the University of Chicago, where Enrico Fermi and his group would later convert U²³⁸ to plutonium in the world's first controlled nuclear chain reaction using a chain reacting pile. Seaborg's role was to figure out how to extract the tiny bit of plutonium from the mass of uranium. Plutonium - 239 was isolated in visible amounts using a transmutation reaction on August 20, 1942 and weighed on September 10, 1942 in Seaborg's Chicago laboratory. He was responsible for the multi - stage chemical process that separated, concentrated and isolated plutonium. This process was further developed at the Clinton Engineering Works in Oak Ridge, Tennessee, and then entered full scale production at the Hanford Engineer Works, in Richland, Washington.

Seaborg's theoretical development of the actinide concept resulted in a redrawing of the Periodic Table of the Elements into its current configuration with the actinide series appearing below the lanthanide series. Seaborg developed the chemical elements americium and curium while in Chicago. He managed to secure patents for both elements. His patent on curium never proved commercially viable because of the element's short half - life. Americium is commonly used in household smoke detectors, however, and thus provided a good source of royalty income to Seaborg in later years. Prior to the test of the first nuclear weapon, Seaborg joined with several other leading scientists in a written statement known as the Franck Report (secret at the time but since published) calling on President Truman to conduct a public demonstration of the atomic bomb witnessed by the Japanese rather than engaging in a surprise attack. Truman instead proceeded to drop two bombs, credited by most observers at the time with ending the war, a uranium bomb on Hiroshima and a plutonium bomb on Nagasaki.

After the conclusion of World War II and the Manhattan Project, Seaborg was eager to return to academic life and university research free from the restrictions of wartime secrecy. In 1946, he added to his responsibilities as a professor by heading the nuclear chemistry research at the Lawrence Radiation Laboratory operated by the University of California on behalf of the United States Atomic Energy Commission. Seaborg was named one of the "Ten Outstanding Young Men in America" by the U.S. Junior Chamber of Commerce in 1947 (along with Richard Nixon and others). Seaborg was elected to the National Academy of Sciences in 1948. From 1954 to 1961 he served as associate director of the radiation laboratory. He was appointed by President Truman to serve as a member of the General Advisory Committee of the Atomic Energy Commission, an assignment he retained until 1960.

Seaborg served as chancellor at University of California, Berkeley, from 1958 to 1961. His term as Chancellor came at a time of considerable controversy during the time of the free speech movement. In October 1958, he announced that the University had relaxed its prior prohibitions on political activity on a test basis. Seaborg served on the Faculty Athletic Committee for several years and is the co-author of a book concerning the Pacific Coast Conference scandal and the founding of the Pac-10 (formerly Pac-8), in which he played a role. Seaborg served on the President's Science Advisory Commission during the Eisenhower administration, which produced the report "Scientific Progress, the Universities, and the Federal Government," also known as the "Seaborg Report," in November 1960. The Seaborg Report is credited with influencing the federal policy towards academic science for the next eight years. In 1959, he helped found the Berkeley Space Sciences Laboratory with UC president Clark Kerr.

After appointment by President John F. Kennedy and confirmation by the United States Senate, Seaborg was chairman of the United States Atomic Energy Commission (AEC) from 1961 to 1971. His pending appointment by President Kennedy was nearly derailed in late 1960 when members of the Kennedy transition team learned that Seaborg had been listed in a U.S. News and World Report article as a member of "Nixon's Brain Trust." Seaborg said that as a lifetime Democrat he was baffled when the article appeared associating him with Vice President Nixon, whom he considered a casual acquaintance.

While chairman of the AEC, Seaborg participated on the negotiating team for the Limited Test Ban Treaty (LTBT). Seaborg considered his contributions to the achievement of the LTBT as his greatest accomplishment. Despite strict rules from the Soviets about photography at the signing ceremony, Seaborg sneaked a tiny camera past the Soviet guards to take a close-up photograph of Soviet Premier Nikita Khrushchev as he signed the treaty.

Seaborg was ardent supporter of large scale massive nuclear plants for electricity generation despite concerns by industry insiders that such large plants were vulnerable in that their nuclear cores could not be properly contained in the event of an accident or operating emergency. Seaborg received a letter dated August 16, 1966 from industry engineers expressing these concerns at the time of the licensing of New York's Indian Point reactor. This letter advised Seaborg and other AEC senior members of these containment concerns which would later become known as the "China Syndrome" resulting from uncontained core meltdowns. Seaborg directed this letter not be released to the public as he feared it would be misunderstood and therefore damage the nuclear industry in the public's view even though the law required such letters be released for public disclosure. This disclosure first came to light for public view in the BBC documentary series, "Pandora's Box, A Is For Atom" dealing with the early history of commercial nuclear development.

Seaborg enjoyed a close relationship with President Lyndon Johnson and influenced the administration to pursue the Nuclear Non - Proliferation Treaty.

Seaborg was called to the White House in the first week of the Nixon Administration in January 1969 to advise President Richard Nixon on his first diplomatic crisis involving the Soviets and nuclear testing. Seaborg clashed with Nixon presidential adviser John Ehrlichman over the treatment of a Jewish scientist whom the Nixon administration suspected of leaking nuclear secrets to Israel.

Seaborg published several books and journal articles during his tenure at the Atomic Energy Commission. His predictions concerning development of stable super - heavy elements are considered among his most important theoretical contributions. Seaborg theorized the transactinide series and the superactinide series of undiscovered synthetic elements. While most of these theoretical future elements have extremely short half - lives and thus no expected practical applications, Seaborg theorized an island of stability for isotopes of certain elements.

When Seaborg resigned as chairman of the Atomic Energy Commission in 1971, he had served longer than any other Kennedy appointee.

Following his service as Chairman of the Atomic Energy Commission, Seaborg returned to UC Berkeley where he was awarded the position of University Professor. At the time, there had been fewer University Professors at UC Berkeley than Nobel prize winners. He also served as Chairman of the Lawrence Hall of Science. Seaborg served as President of the American Association for the Advancement of Science in 1972 and as President of the American Chemical Society in 1976. In 1976, when the Swedish king visited the United States, Seaborg played a major role in welcoming the Swedish Royal Family.

In 1980, he transmuted several thousand atoms of bismuth into gold at the Lawrence Berkeley Laboratory. His experimental technique, using nuclear physics, was able to remove protons and neutrons from the bismuth atoms. Seaborg's technique would have been far too expensive to enable routine manufacturing of gold, but his work is the closest to the mythical Philosopher's Stone.

In 1983, President Ronald Reagan appointed Seaborg to serve on the National Commission on Excellence in Education. Upon seeing the final draft report, Seaborg is credited with making comments that it was far too weak and did not communicate the urgency of the current crisis. He compared the crisis in education to the arms race, and stated that we are "a nation at risk." These comments led to a new introduction to the report and gave the report the famous title which focused national attention on education as an issue germane to the federal government.

Seaborg lived most of his later life in Lafayette, California, where he devoted himself to editing and publishing the journals that documented both his early life and later career. He rallied a group of scientists who criticized the science curriculum in the State of California which he viewed as far too socially oriented and not nearly focused enough on hard science. California Governor Pete Wilson appointed Seaborg to head a committee that proposed sweeping changes to California's science curriculum despite outcries from labor organizations and others.

On August 24, 1998, while in Boston to attend a meeting by the American Chemical Society, Seaborg suffered a stroke, which led to his death six months later on February 25, 1999 at his home in Lafayette.

During his lifetime, Seaborg is said to have been the author or co-author of more than 50 books and 500 scientific journal articles, many of them brief reports on fast breaking discoveries in nuclear science while other subjects, most notably the actinide concept, represented major theoretical contributions in the history of science. He held more than 40 patents — among them the only patents ever issued for chemical elements, americium and curium. He is also said to have received more than 50 degrees and honorary degrees in his lifetime. At one time, he was listed in the Guinness Book of World Records as having the longest entry in Marquis Who's Who in America. In February 2005, Seaborg was posthumously inducted into the National Inventors Hall of Fame.

In 1942, Seaborg married Helen Griggs, the secretary of Ernest Lawrence.

Under wartime pressure, Seaborg had moved to Chicago while engaged to Griggs. When Seaborg returned to accompany Griggs for the journey back to Chicago, friends expected them to marry in Chicago. But, eager to be married, Seaborg and Griggs impulsively got off the train in the town of Caliente, Nevada, for what they thought would be a quick wedding. When they asked for City Hall, they found Caliente had none — they would have to travel 25 miles north to Pioche, the county seat. With no car, this was no easy feat but, happily, one of Caliente's newest deputy sheriffs turned out to be a recent graduate of the Cal Berkeley chemistry department and was more than happy to do a favor for Seaborg. The deputy sheriff arranged for the wedding couple to ride up and back to Pioche in a mail truck. The witnesses at the Seaborg wedding were a clerk and a janitor.

Glenn Seaborg and Helen Griggs Seaborg had six children, of whom the first, Peter Glenn Seaborg, died in 1997. The others were Lynne Seaborg Cobb, David Seaborg, Steve Seaborg, Eric Seaborg, and Dianne Seaborg.

Seaborg was an avid hiker. Upon becoming Chairman of the Atomic Energy Commission in 1961, he commenced taking daily hikes through a trail which he blazed at the headquarters site in Germantown, Maryland. He frequently invited colleagues and visitors to accompany him and the trail became known as the "Glenn Seaborg Trail."

He and his wife Helen are credited with blazing a 12 mile trail in the East Bay area near their Lafayette, California, home. This trail has since become a part of the American Hiking Association's cross - country network of trails. Seaborg and his wife walked the trail network from Contra Costa County all the way to the California - Nevada border.

Seaborg was honored as Swedish - American of the Year in 1962 by the Vasa Order of America. In 1991, the organization named "Local Lodge Glenn T. Seaborg No. 719" in his honor during the Seaborg Honors ceremony at which he appeared. This lodge maintains a scholarship fund in his name, as does the unrelated Swedish - American Club of Los Angeles.

Seaborg kept a close bond to his Swedish origin. He visited Sweden every so often and his family were members of the Swedish Pemer Genealogical Society, a family association open for every descendant of the Pemer family, a Swedish family with German origin, from which Seaborg was descended on his mother's side.

He was elected a foreign member of the Royal Swedish Academy of Sciences in 1972 and the Royal Society of London.

Seaborg was an enthusiastic supporter of Cal's sports teams. San Francisco columnist Herb Caen was fond of pointing out that Seaborg's surname is an anagram of "Go Bears", a popular cheer at UC Berkeley.

The element seaborgium was named after Seaborg by Albert Ghiorso, E. Kenneth Hulet, and others, who also credited Seaborg as a co-discoverer. It was so named while Seaborg was still alive, which proved controversial. He influenced the naming of so many elements that with the announcement of seaborgium, it was noted in Discover magazine's review of the year in science that he could receive a letter addressed in chemical elements: seaborgium, lawrencium (for the Lawrence Berkeley Laboratory where he worked), berkelium, californium, americium.

While it has been commonly stated that seaborgium is the only element to have been named after a living person, this is not entirely accurate; both einsteinium and fermium were proposed as names of new elements discovered by Albert Ghiorso while Enrico Fermi and Albert Einstein were still living. The discovery of these elements and their names were kept secret under Cold War era nuclear secrecy rules, however, and thus the names were not known by the public or the broader scientific community until after the deaths of Fermi and Einstein. Thus, seaborgium is the only element to have been publicly named after a living person.