Cleveland Abbe ushered in the modern era of meteorology by instituting a national system of daily weather reports and forecasts that served as the prototype for the U.S. Weather Bureau, which he also helped to organize. Abbe helped transform the reporting of weather from a highly localized phenomenon based on conjecture into a coordinated system […]

Ackerman, Thomas P. (1947- ) American Meteorologist (Scientist)

The theory of nuclear winter, or the catastrophic atmospheric consequences wrought by nuclear war, elicited a sea change in the public perception of the viability of employing nuclear weapons tactically. Thomas Ackerman participated on the team that proposed a scientific model for a nuclear winter scenario in the early 1980s. The theory’s reception varied along […]

Agricola, Georgius (1494-1555) German Mineralogist, Geologist, Metallurgist (Scientist)

Though his exhaustive knowledge of diverse subjects earned him the title "The Saxon Pliny," Georgius Agricola was best known as the author of De re metallica libri XII (On the Subject of Metals), a seminal text in the understanding of metallurgy and the mining and smelting processes of the time. Living in the mining capitals […]

Aiken, Howard Hathaway (1900-1973) American Computer Engineer (Scientist)

Howard Aiken helped usher in the computer age by inventing the Harvard Mark I and Mark II, the precursors to modern digital computers. The New York Times hailed the significance of his invention: "At the dictation of a mathematician, it will solve in a matter of hours equations never before solved because of their intricacy […]

Alfven, Hannes (1908-1995) Swedish Astrophysicist (Scientist)

Although Hannes Alfven’s name graces many physical phenomena that he identified—Alfven waves and the Alfven speed, Alfven layers, Alfven critical points, Alfven radii, and Alfven distances—his actual role in the advancement of astrophysics has been obscured by the belated acceptance accorded many of his discoveries. He received the 1970 Nobel Prize for "his contributions and […]

Allen, Paul (1953- ) American Computer Engineer (Scientist)

Paul Allen collaborated with Bill Gates to found Microsoft, the computer software company that provided the programming for almost all personal computer applications. Allen and Gates wrote the programming that launched the company, though as their company expanded, they exerted their visionary influence by wedding hardware with the appropriate software. Although Allen did not actually […]

Alvarez, Luis Walter (1911-1988) American Physicist (Scientist)

In his first years as a research physicist at the University of California at Berkeley in the 1930s, Luis Alvarez earned the title "prize wild idea man," which acknowledged both his wide-ranging investigations and his ability to identify important questions in need of solutions. A member of the Manhattan Project that developed the atomic bomb […]

Ampere, Andre-Marie (1775-1836) French Physicist, Mathematician (Scientist)

A mathematical child prodigy self-educated according to the principles of Rousseau, Andre Ampere established his scientific significance after a fit of inspiration in September and October of 1820, when he developed the science of electrodynamics. Both Ampere’s Law, which established the mathematical relationship between electricity and magnetism, and the ampere, or amp, a unit for […]

Apgar, Virginia (1909-1974) American Physician (Scientist)

Physician Virginia Apgar’s best-known contribution to the medical sciences was the development of a test designed to evaluate the health of a newborn. This breakthrough system helped save the lives of many infants and became a standard procedure in hospitals worldwide. Apgar made numerous other advances in obstetric anesthesia and raised the awareness Americans had […]

Appert, Nicolas (1752-1841) French Food Technologist (Scientist)

Nicolas Appert invented the food-preserving process of boiling (and thereby sterilizing) food in glass jars—the basis of modern canning. His invention freed people from the need for fresh food, allowing them to preserve it by an easy process (as opposed to salting or smoking), enabling food to be kept over long periods of time. Appert […]