Book contents
- Time: From Earth Rotation to Atomic Physics
- Time: From Earth Rotation to Atomic Physics
- Copyright page
- Dedication
- Contents
- Preface
- 1 Time Before the 20th Century
- 2 Time from the Earth’s Rotation
- 3 Ephemerides
- 4 Variable Earth Rotation
- 5 Earth Orientation
- 6 Ephemeris Time
- 7 Relativity and Time
- 8 Time and Cosmology
- 9 Dynamical and Coordinate Timescales
- 10 Clock Developments
- 11 Microwave Atomic Clocks
- 12 Optical Atomic Standards
- 13 Definition and Role of a Second
- 14 International Atomic Time (TAI)
- 15 Coordinated Universal Time (UTC)
- 16 Time in the Solar System
- 17 Time and Frequency Transfer
- 18 Modern Earth Orientation
- 19 International Activities
- 20 Time Applications
- 21 Future of Timekeeping
- Acronyms
- Glossary
- Index
- References
15 - Coordinated Universal Time (UTC)
Published online by Cambridge University Press: 01 October 2018
Book contents
- Time: From Earth Rotation to Atomic Physics
- Time: From Earth Rotation to Atomic Physics
- Copyright page
- Dedication
- Contents
- Preface
- 1 Time Before the 20th Century
- 2 Time from the Earth’s Rotation
- 3 Ephemerides
- 4 Variable Earth Rotation
- 5 Earth Orientation
- 6 Ephemeris Time
- 7 Relativity and Time
- 8 Time and Cosmology
- 9 Dynamical and Coordinate Timescales
- 10 Clock Developments
- 11 Microwave Atomic Clocks
- 12 Optical Atomic Standards
- 13 Definition and Role of a Second
- 14 International Atomic Time (TAI)
- 15 Coordinated Universal Time (UTC)
- 16 Time in the Solar System
- 17 Time and Frequency Transfer
- 18 Modern Earth Orientation
- 19 International Activities
- 20 Time Applications
- 21 Future of Timekeeping
- Acronyms
- Glossary
- Index
- References
Summary
In the 19th century, many local timescales and reference meridians were in practical use. The railroad companies pushed for time standardization and navigators wanted a standard meridian. In 1884, the Greenwich meridian was adopted as the international prime meridian for longitude and time zones. In 1928, Universal Time (UT) was recommended to replace Greenwich Mean Time (GMT) and the BIH was to coordinate transmission of radio time signals. In 1960, the United Kingdom and the United States began to coordinate time transmissions by making the same adjustments to their clocks at the same times. In 1972, the International Radio Consultative Committee (CCIR), a predecessor organization of the International Telecommunications Union, introduced a new definition of UTC, which is based on TAI with leap seconds in order to keep UTC within 0.9s of UT1. UTC is now distributed and used worldwide. Since 2000 there has been discussion of redefining UTC without leap seconds. A number of meetings, proceedings, and papers have been devoted to this possibility. Arguments for and against are presented.
- Type
- Chapter
- Information
- Time: From Earth Rotation to Atomic Physics , pp. 249 - 261Publisher: Cambridge University PressPrint publication year: 2018
References
Arias, E. F., Combrinck, L., Gabor, P., Hohenkerk, C. Y., & Seidelmann, P. K., eds. (2017). The Science of Time 2016. Springer.CrossRefGoogle Scholar
Bartky, I. R. (2000). Selling the True Time, Nineteenth-Century Timekeeping in America. Stanford, CA: Stanford University Press.CrossRefGoogle Scholar
Blaise, C. (2002). Time Lord, Sir Stanford Fleming and the Creation of Standard Time. New York, NY: Random House.Google Scholar
Fleming, S. (1879a). Time-Reckoning. Proceedings of the Canadian Institute, 1, 97–137.Google Scholar
Fleming, S. (1879b). Longitude and Time-Reckoning. Proceedings of the Canadian Institute, 1, 138–149.Google Scholar
Hirsch, A. & Von Oppolzer, T. (1883). Unification des Longitudes par l’Adoption d’un Méridien initial unique et Introduction d’une Heure Universelle, Bureau central de l’Association géodésique internationale.Google Scholar
International Conference Held at Washington for the Purpose of Fixing a Prime Meridian and a Universal Day, October 1884 – Protocols of the Proceedings.Google Scholar
Nelson, R. A., McCarthy, D. D., Malys, S., Levine, J., Guinot, B., Fliegel, H. F., Beard, R. L., & Bartholomew, E. R. (2001). The Leap Second: Its History and Possible Future. Metrologia, 38, 509–529.CrossRefGoogle Scholar
Seago, J. H., Seaman, R. L., & Allen, S. L., eds. (2011). Decoupling Civil Timekeeping and Earth Rotation. A Colloquium Exploring Implications of Redefining Coordinated Universal Time (UTC). AAS Science and Technology Series, 113, San Diego, CA: Univelt, Inc.Google Scholar
Seago, J. H., Seaman, R. L., Seidelmann, P. K., & Allen, S. L., eds. (2013). Requirements for UTC and Civil Timekeeping on Earth. A Colloquium Addressing a Continuous Time Standard. AAS Science and Technology Series, 115, San Diego: Univelt, Inc.Google Scholar
Trans. Int. Astron. Union (1968). Vol. XIII B, Proc. 13th General Assembly, Prague, 1967, Perek, L., ed., Dordrecht: Reidel, 181.Google Scholar
Wheeler, G. M. (1885). Report upon the Third International Geographic Congress and Exhibition at Venice, Italy, 1881, Washington, DC: US Government Printing Office.Google Scholar