November 18

Born in Verona, Hippolytus Guarinonius studied medicine at the University of Padua and became renowned for his expertise in pharmacology and anatomy. He served as a papal physician in Rome and corresponded with scholars across Europe on topics ranging from medicine to natural philosophy. Guarinonius authored works on practical alchemy and health regimens that blended traditional remedies with experimental approaches. He collected rare manuscripts, coins, and artifacts, reflecting his wide-ranging interests. His interdisciplinary pursuits exemplified the scholarly spirit of the Renaissance. He died in 1654, leaving behind manuscripts that influenced both medical and esoteric traditions.

Philibert Commerson served as the naturalist on Louis Antoine de Bougainville’s global expedition from 1766 to 1769. He meticulously documented flora and fauna in South America, Tahiti, and the Pacific Islands, and was the first to gather specimens of the bougainvillea flower. Commerson’s detailed notes and illustrations enriched European botanical gardens and scientific publications. Plagued by health issues, he remained in Mauritius after the voyage and continued his studies, amassing a vast herbarium. His discoveries advanced the taxonomy of tropical plants and inspired later explorers such as Joseph Banks. Commerson died in 1773, and his contributions endure in botanical nomenclature.

Born in Paris, New York, he became the leading American botanist of the 19th century and a prominent professor at Harvard University. Gray authored Gray's Manual of Botany, which became the authoritative reference for North American plant species. He was one of the first scientists in the United States to embrace Darwin's theory of natural selection and promoted its acceptance among American naturalists. He collaborated extensively with European botanists, exchanging specimens and research that enriched global botanical knowledge. His work established systematic botany as a rigorous scientific discipline in America. His legacy includes numerous plant genera named in his honor and foundational contributions to plant taxonomy and biogeography.

Born in Finland to a Swedish-speaking family, he studied geology at Uppsala University and developed expertise in polar geography. He led several Arctic expeditions in the 1860s and 1870s, mapping previously uncharted coastlines of Greenland and Siberia. In 1878-79, he commanded the steamship Vega on the first complete voyage through the Northeast Passage, a milestone in exploration history. He published extensive scientific accounts of his observations, contributing to geology, oceanography, and meteorology. He later served as director of the Geological Survey of Finland, advancing research and education in earth sciences. His pioneering work expanded the boundaries of exploration and deepened understanding of the Arctic regions.

August Kundt was a pioneering German physicist known for his work in acoustics and material science. He invented the Kundt's tube, an apparatus used to measure the speed of sound in gases and solids. As a professor at the University of Strasbourg and later the University of Berlin, he mentored many future scientists. His experiments laid the groundwork for modern studies in wave propagation. Kundt's dedication to precision measurement influenced techniques in experimental physics that are still in use today.

Frances Gertrude McGill (1882–1959) was one of Canada's first female forensic pathologists and a pioneer in forensic science. She conducted groundbreaking work identifying toxins in autopsies and developed systematic approaches to crime scene analysis in Saskatchewan. McGill's expertise was sought by law enforcement across North America, where she consulted on complex homicide and accident cases. She lectured in medical schools and published influential papers that helped professionalize forensic pathology. Known as 'The Sorceress of the Morgue', McGill's dedication laid the foundation for modern forensic techniques in Canada and beyond.

Patrick Blackett (1897–1974) won the Nobel Prize in Physics in 1948 for his investigations into cosmic rays and particle physics. During World War II, he led pioneering operational research efforts to improve military strategy and logistics. As a professor at Imperial College London, he advanced techniques in geomagnetism and geophysics, impacting both academic and applied sciences. Blackett also advised governments on atomic energy policy and was an early advocate for arms control. His leadership bridged experimental physics with practical problem-solving across scientific disciplines.

George Horace Gallup (1901-1984) established the American Institute of Public Opinion in 1935 and developed scientific survey methods to measure public attitudes. His Gallup Poll became a leading source of data on politics, social trends and consumer confidence. Gallup authored influential books on polling techniques and helped legitimize survey research in journalism and academia. His work laid the foundation for modern opinion polling and market research worldwide.

George Wald (1906-1997) was a biologist and professor at Harvard University who shared the 1967 Nobel Prize in Physiology or Medicine for his discoveries on visual pigments and the role of vitamin A in vision. He conducted pioneering studies on retinal photochemistry and pigment regeneration, laying the foundation for modern vision science. Wald authored numerous scientific papers and was an outspoken advocate for nuclear disarmament and environmental conservation. His work continues to influence research in neuroscience and biochemistry.

Born in Aarhus, Østergaard studied psychology at the University of Copenhagen and earned her doctorate in clinical psychology. She lectured at the university and published research on personality and mental health. In 1982, she joined Poul Schlüter's cabinet as Minister for Culture and Minister for Nordic Cooperation. She advocated for cultural programs, youth engagement, and greater collaboration among Nordic countries. After leaving government in 1986, she continued her academic work and influenced Danish cultural policy. Østergaard remained active in the Social Democratic Party until her death in 1996.

Ed Krupp (born 1944) is an American astronomer and archaeoastronomer, serving as the director of Los Angeles's Griffith Observatory since 1974. He is renowned for his engaging public lectures, television appearances, and popular books that make astronomy accessible to a broad audience. Krupp's research explores the cultural and historical aspects of astronomy, investigating how ancient civilizations interpreted celestial phenomena. He founded the Institute for Archaeoastronomy and Cultural Astronomy, advancing the understanding of astronomical practices in prehistoric societies. Under his guidance, Griffith Observatory hosts regular public star parties and exhibitions, drawing millions of visitors and fostering science education. Through his work, Krupp has inspired generations of amateur and professional astronomers, leaving a lasting impact on public outreach and archaeological astronomy.

Jim Weirich authored Rake in 2004 as a domain-specific language for task automation, which became a staple in Ruby development and influenced build tools in other ecosystems. A dedicated advocate for open-source software, Weirich contributed to RubyGems and spoke at conferences worldwide, inspiring developers with his practical and humorous teaching style. As a board member of O’Reilly’s conference programs and a mentor to many, he fostered collaboration and innovation in the programming community. Weirich’s unexpected passing in 2014 was mourned by developers globally, but his work lives on in tools and practices he helped establish. His legacy continues to drive software craftsmanship and community engagement.