The minute is a unit of time or angle. As a unit of time, the minute is most of times equal to 1⁄60 (the first sexagesimal fraction) of an hour, or 60 seconds. In the UTC time standard, a minute on rare occasions has 61 seconds, a consequence of leap seconds (there is a provision to insert a negative leap second, which would result in a 59-second minute, but this has never happened in more than 40 years under this system). As a unit of angle, the minute of arc is equal to 1⁄60 of a degree, or 60 seconds (of arc). Although not an SI unit for either time or angle, the minute is accepted for use with SI units for both. The SI symbols for minute or minutes are min for time measurement, and the prime symbol after a number, e.g. 5′, for angle measurement. The prime is also sometimes used informally to denote minutes of time.
One of the earliest known uses of the minute (and the second) is found in John of Sacrobosco's Computus (ca. 1235), where he used them when discussing the length of the tropical year. No earlier records for the origin of the minute as 1⁄60 of the hour and the second 1⁄60 of the minute have ever been found. Another motivation that has been suggested for the emergence of these fine divisions of time was the construction of "precision" timepieces (mechanical and water clocks).
Historically, the word "minute" comes from the Latin pars minuta prima, meaning "first small part". This division of the hour can be further refined with a "second small part" (Latin: pars minuta secunda), and this is where the word "second" comes from. For even further refinement, the term "third" (1⁄60 of a second) remains in some languages, for example Polish (tercja) and Turkish (salise), although most modern usage subdivides seconds by using decimals. The symbol notation of the prime for minutes and double prime for seconds can be seen as indicating the first and second cut of the hour (similar to how the foot is the first cut of the yard or perhaps chain, with inches as the second cut). In 1267, the medieval scientist Roger Bacon, writing in Latin, defined the division of time between full moons as a number of hours, minutes, seconds, thirds, and fourths (horae, minuta, secunda, tertia, and quarta) after noon on specified calendar dates.
Notes and referencesEdit
- "What is the origin of hours, minutes and seconds?". Wisteme. Archived from the original on 24 March 2012. Retrieved 2011-05-25.
What we now call a minute derives from the first fractional sexagesimal place.
- "Non-SI units accepted for use with the SI, and units based on fundamental constants". Bureau International de Poids et Mesures. Retrieved 2011-05-25.
- Nothaft, C. Philipp E. (2018), Scandalous Error: Calendar Reform and Calendrical Astronomy in Medieval Europe, Oxford: Oxford University Press, p. 126, ISBN 9780198799559,
Sacrobosco switched to sexagesimal fractions, but rendered them more congenial to computistical use by applying them not to the day but to the hour, thereby inaugurating the use of hours, minutes, and seconds that still prevails in the twenty-first century.
- R Bacon (2000) . The Opus Majus of Roger Bacon. BR Belle. University of Pennsylvania Press. table facing page 231. ISBN 978-1-85506-856-8.