Kelvin (K) - Founded by William Thomson, 1st Baron Kelvin
Founder: William Thomson, 1st Baron Kelvin History: Named after the Scottish physicist William Thomson, who was later titled Lord Kelvin. The Kelvin scale is an absolute temperature scale, with 0 K representing absolute zero, the theoretical lowest possible temperature at which all molecular motion ceases.
Celsius (°C) - Founded by Anders Celsius
Founder: Anders Celsius
History: Named after the Swedish astronomer Anders Celsius, who proposed the Celsius temperature scale in 1742. Originally, Celsius defined 0 as the boiling point and 100 as the freezing point of water, but the scale was later reversed to its current form.
Fahrenheit (°F) - Founded by Daniel Gabriel Fahrenheit
Founder: Daniel Gabriel Fahrenheit History: Developed by the German physicist Daniel Gabriel Fahrenheit in the early 18th century. Fahrenheit chose the freezing point of a mixture of water, ice, and salt as 0°F and the average human body temperature as 96°F, later adjusted to 98.6°F.
Réaumur (°Ré) - Founded by René Antoine Ferchault de Réaumur
Founder: René Antoine Ferchault de Réaumur History: Named after the French scientist René Antoine Ferchault de Réaumur, who introduced this temperature scale in 1730. Réaumur defined 0°Ré as the freezing point of water and 80°Ré as the boiling point of water. Réaumur invented the Réaumur scale, a temperature scale where the freezing point of water is set to 0°Ré and the boiling point to 80°Ré. He proposed this scale in 1730 as an improvement over existing temperature scales of his time. The Réaumur scale was widely used in Europe, particularly in France, during the 18th and 19th centuries. In addition to his work on temperature measurement, Réaumur made important contributions to the study of insects (entomology). He published several volumes of "Mémoires pour servir à l'histoire des insectes" ("Memoirs for the History of Insects"), where he documented his observations and experiments on the life cycles, behaviors, and anatomy of various insect species. Réaumur's scientific legacy continues to be recognized and celebrated today, particularly in the fields of temperature measurement and entomology. His name lives on through the Réaumur scale, which, although not as widely used as the Celsius or Fahrenheit scales today, remains an important part of the history of thermometry.
Delisle (°De) - Founded by Joseph-Nicolas Delisle
Founder: Joseph-Nicolas Delisle History: Named after the French astronomer Joseph-Nicolas Delisle, who proposed the Delisle temperature scale in 1732. In this scale, the boiling point of water is set at 0°D, and the freezing point at 150°D, with the scale decreasing as temperature increases. The Delisle temperature scale was invented by Joseph-Nicolas Delisle, a French astronomer and engineer, in the early 18th century. Delisle was born on April 4, 1688, in Paris, France, and he made significant contributions to various fields of science, including astronomy, physics, and cartography. Joseph-Nicolas Delisle is best known for his work in astronomy, particularly his studies of planetary motion and the shape of the Earth. In addition to his work in astronomy, Delisle also made important contributions to the field of cartography, developing methods for accurately measuring distances on maps. Delisle's temperature scale, which he introduced in 1732, was based on the concept of using the freezing and boiling points of water as reference points for measuring temperature. However, unlike many other temperature scales, Delisle's scale was inverted, with the freezing point of water set at 0 degrees and the boiling point at 150 degrees. Despite its historical significance, the Delisle temperature scale fell out of favor in the late 18th and early 19th centuries as other temperature scales, such as Celsius and Fahrenheit, gained popularity. Today, the Delisle scale is not widely used, but it remains an important part of the history of temperature measurement.
Newton (°N) - Founded by Isaac Newton
Founder: Isaac Newton History: Named after the English mathematician and physicist Sir Isaac Newton. The Newton scale, also known as the Newtonian scale, was based on a 0°N freezing point and a 33°N boiling point of water, with 0°N equal to the temperature at which water freezes and 33°N equal to the temperature at which water boils.
Rømer (°Rø) - Founded by Ole Rømer
Ole Rømer was a Danish astronomer born on September 25, 1644, in Århus, Denmark, and died on September 19, 1710, in Copenhagen, Denmark. He is best known for his contributions to the field of astronomy, particularly for his measurement of the speed of light. Rømer's small history revolves around his groundbreaking observation of the speed of light. In 1676, while working at the Royal Observatory in Paris under the supervision of the French astronomer Jean Picard, Rømer made a significant discovery regarding the apparent motion of Jupiter's moon, Io. His work laid the foundation for further studies on the nature of light and the development of modern physics. Rømer's observations and calculations were instrumental in shaping our understanding of the universe and have earned him a lasting place in the history of science. Rømer's realization led him to make the groundbreaking hypothesis that light has a finite speed and does not travel instantaneously. He estimated the speed of light to be about 220,000 kilometers per second, which was a remarkable achievement given the limited technological resources available at the time.
