In 1997, American biology professor Stanley B. Prusiner won the Nobel Prize for medicine for discovering "prions," described as "an entirely new genre of disease-causing agents.

In 1971, the mole - the amount of substance (matter) - was adopted as a chemical measurement added to the six base quantities of the SI (International System of scientific units). The decision was made by the Conférence Général des Poids et Mesures (CGPM), the principal executive organization under the Treaty of the Meter. IUPAC's participation was led by M.L. McGlashan. The mole is the amount of substance of a system which contains as many elementary entities as there are carbon atoms in 0.012 kg of carbon 12. The elementary entities must be specified and may be atoms, molecules, ions, electrons, other particles, or specified groups of such particles. The agreed symbol for the unit is mol, and the symbol for amount of substance is n.

In 1608, Johannes Lippershey (c.1570-c.1619) demonstrated a new invention, the first optical (refracting) telescope - prototype of the modern telescopes - to the Netherlands States General. Lippershey was a lens grinder who furnished spectacles. An apprentice discovered that - by separating both a long-focus lens and a short-focus lens in front of the eye - distant objects appeared closer. Lippershey mounted lenses in tubes, applied for a patent in 1608, and also offered them for sale to the Dutch government, which appreciated their military value. When Galileo heard of the device, he made a similar arrangement and used it to study the heavens. It was named a "telescope" by a guest at an outdoor banquet 14 Apr 1611 honouring Galileo, where he demonstrated it to the assembly.

In 1956, The Physical Review published a paper by Tsung Dao Lee and Chen Ning Yang on the Question of Parity Conservation in Weak Interactions. They addressed an issue that had long been believed, but for which there had been no experimental support. Yet, there existed a Theta-Tau Puzzle (C.F. Powell, 1949) in the disintegration of certain cosmic ray particles via the nuclear weak force.  Lee and Yang believed this was because of parity violation, which contradicted the generally accepted "law" of conservation of parity. They proposed a study of experiments involving weak interactions. Chien-Shiung Wu validated non-conservation of parity on 27 Dec 1956 in their suggestion to study beta decay of cobalt-60.

In 1957, the Space Age began as the Soviet Union, to the dismay of the United States, launched Sputnik, the first manmade satellite, into orbit around the earth. The craft circled the earth every 95 minutes at almost 20,000 miles per hour 500 miles above the Earth. The Sputnik (meaning "companion" or "fellow traveller") was launched from Kazakhstan. It stayed in orbit for about three months. Sputnik fell from the sky on 4 Jan 1958. The 184-lb satellite had transmitted a radio signal picked up around the world, and instrumentation for temperature measurement.