February 28

Born in 1535 in Leuven to the renowned mathematician Gemma Frisius, Cornelius Gemma pursued studies in medicine and astronomy at the University of Leuven. He became a respected academic, conducting celestial observations and publishing treatises on comets in 1577 that combined scientific data with astrological commentary. Gemma’s work reflected the era’s blend of disciplines and captured the fascination with the heavens. His publications influenced subsequent astronomers and contributed to early modern celestial cartography. He died during a plague outbreak in 1578, leaving a modest but notable scientific legacy.

Born in 1552 in Lichtensteig, Switzerland, Jost Bürgi earned renown for both his mathematical innovations and his craftsmanship in clockmaking. He entered the service of the Landgrave of Hesse in Kassel, constructing intricate astronomical instruments and clocks for the court. Around the same time as John Napier, Bürgi devised methods resembling logarithms, significantly simplifying calculations for astronomers. His precision gearwork advanced the accuracy of pendulum clocks and time measurement. Bürgi’s work influenced horology and computational mathematics until his death in 1632.

Born in 1675 in Paris, Guillaume Delisle studied under the Cassini family before joining the French Academy of Sciences as a royal cartographer. He rejected imaginative mapping in favor of empirical measurements, compiling data from explorers and astronomers. Delisle’s maps of Africa, North America, and Asia were unmatched in precision, correcting numerous errors in longitude and latitude that plagued earlier works. His 1700 world map set a new standard, earning him royal patronage and lasting acclaim. Delisle’s dedication to accuracy profoundly influenced the development of modern cartography until his death in 1726.

Born in 1683 in La Rochelle, René Antoine Ferchault de Réaumur became a professor at the Collège de France, specializing in natural history and metallurgy. He published the multi-volume Memoires pour servir à l’histoire des insectes between 1734 and 1742, laying the foundations for systematic entomology. In 1730, he introduced the Réaumur temperature scale, which was widely used in Europe before being supplanted by Celsius. His experiments in metallurgy and contributions to natural history reflected his diverse scientific interests. Réaumur’s meticulous studies earned him membership in the French Academy of Sciences, and he died in 1757.

Born in 1704, Louis Godin joined the French Academy of Sciences and set off in 1735 to Peru with fellow astronomers to determine the length of a degree of latitude near the equator. Their measurements between 1735 and 1744 formed a key part of the Geodesic Mission, confirming that the Earth bulges at the equator. Godin later produced detailed star catalogs and taught mathematics at the Royal Military School in Paris. His work advanced the accuracy of celestial navigation and geodesy. He passed away in 1760, remembered for bridging science and exploration.

Born in 1848 in Lyon, Arthur Giry became a leading figure in medieval studies and one of the founders of modern diplomatics. He taught at the École des Chartes and collated thousands of medieval charters, publishing authoritative editions that remain reference works today. Giry’s rigorous methodologies influenced archival practices and the study of medieval institutions. His collaborative works, such as the 'Cartulaire de Notre-Dame de Paris', exemplify his scholarly precision. He was elected to the French Academy in 1894 and continued his research until his death in 1899.

Pierre Fatou was a pioneering French mathematician born in 1878. He made fundamental contributions to the field of complex analysis, especially through his study of iterations of analytic functions. Fatou introduced concepts now known as Fatou sets and Julia sets, which later became central in fractal geometry. His meticulous research on dynamical systems opened new perspectives in mathematical analysis. During his career, he held professorships and published influential papers that inspired future generations of mathematicians. Fatou's legacy endures in the ongoing study of complex dynamics and fractal theory.

Philip Showalter Hench was born in 1896 and became a leading endocrinologist at the Mayo Clinic. He is best known for his research on adrenal gland hormones and their therapeutic use in treating rheumatoid arthritis. In 1950, he shared the Nobel Prize in Physiology or Medicine with Edward Kendall and Tadeusz Reichstein for the discovery of cortisone. Hench's work transformed the treatment of inflammatory diseases and paved the way for modern steroid therapy. He published numerous articles and served as a mentor to future medical researchers. His contributions have had a lasting impact on medicine and patient care.

Linus Pauling was born in 1901 and made groundbreaking contributions to chemistry and biology. His research on the nature of the chemical bond earned him the Nobel Prize in Chemistry in 1954. Pauling also championed the concept of molecular disease and laid foundations for molecular biology. Later, he became an outspoken peace activist and received the Nobel Peace Prize in 1962 for his efforts against nuclear testing. He authored influential books on chemistry and the benefits of vitamin C. Pauling's interdisciplinary work and advocacy left a profound mark on science and society.

Peter Medawar's groundbreaking experiments demonstrated how the immune system distinguishes self from non-self, laying the foundation for modern organ transplantation. Born in Brazil, he studied at Oxford and served in the Royal Army Medical Corps during World War II. In 1960, Medawar shared the Nobel Prize in Physiology or Medicine for his work on acquired immune tolerance. He later became director of the National Institute for Medical Research in London. Medawar was also a prolific science writer, popularizing biology with accessible essays and lectures. His legacy endures in transplant immunology and science communication.

Leon Cooper co-developed the BCS theory of superconductivity, revolutionizing condensed matter physics. He received the Nobel Prize in Physics in 1972 alongside John Bardeen and John Schrieffer. Cooper was a professor at Brown University, mentoring generations of physicists. His research extended to quantum computing and neural networks, influencing multiple disciplines. Cooper's contributions have had a lasting impact on theoretical and applied physics.

Rein Taagepera is an Estonian political scientist and politician born in 1933. He has made significant contributions to the study of electoral systems, federalism, and political demography. Taagepera has held professorships at leading universities and is known for rigorous quantitative analysis. His publications on legislative seat allocation are widely cited in political science. During Estonia’s early independence, he applied his academic insights to public service and governance. Taagepera’s blend of scholarship and public service continues to influence political thought and practice.