Janaki asal-mulanya gasan Waktu Universal Takoordinasi

{{redirect|UTC}}
{| class="wikitable" style="float: right;"
|+Waktu saat ini
|{{nowrap|{{CURRENTTIME}}, {{CURRENTDAY}} {{CURRENTMONTHNAME}} {{CURRENTYEAR}}}} (UTC) – <span class="plainlinks" id="purgelink">{{nowrap|[{{fullurl:{{FULLPAGENAME}}|action=purge}} Muat ulang halaman]}}</span></div>
|}
'''Waktu Universal Terkoordinasi''' (bahasa Inggris: ''Coordinated Universal Time'', bahasa Prancis: ''Temps Universel Coordonné'', singkatan resmi: '''UTC'''{{fn|1}}), sering disebut sebagai '''Waktu Zulu''' adalah pawujudan matan waktu atom matan [[Waktu Universal]] (UT) atawa [[Waktu Greenwich]] (GMT). Waktu ini adalah dasar dari [[waktu sipil]]. [[Zona waktu]] di sabarataan dunia adalah ditampaiakan sebagai tambahan positif atau negatif dari UT. Beda UTC dari [[Waktu Atom Internasional]] adalah sejumlah beberapa detik genap (bukan pecahan), sesuai lawan waktu yang dihitung oleh jam atom. Beda UTC dari UT hanya sepersekian detik.

UTC adalah ukuran waktu campuran: kecepatan dari UTC adalah berdasarkan yang dihitung oleh standar jam atom, tetapi [[epoch]] dari UTC dicocokkan selalu supaya dekat lawan waktu UT yang berdasarkan data astronomi. Putaran [[bumi]] sedikit demi sedikit mengalami perlambatan (karena efek pengereman oleh pasang-surut), sehingga [[Waktu Matahari|mean hari matahari]] semakin bertambah semenjak diperkenalkannya TAI. Karena alasan ini, UT adalah "lebih lambat" dari TAI. UTC selalu dipertahankan untuk berada dalam 0.9 detik dari [[Universal Time|UT1]] (UT1 adalah satu dari tiga definisi UT yang paling akurat); [[detik kabisat]] akan ditambahkan ke (atau mungkin bisa juga dikurangkan dari) UTC disetiap akhir bulan. Hingga saat ini, penambahan/pengurangan detik kabisat ini (yang pertama tahun 1972) selalu dalam harga positif, dan dilakukan pada tanggal 30 Juni atau 31 Desember, di mana penambahan detik kabisat dinamakan sebagai jam 23:59:60. Pengumuman dari detik kabisat ini dilakukan oleh ''[[International Earth Rotation and Reference Systems Service]]'' (IERS - Sistem Internasional Pelayanan Putaran Bumi dan Referensi), berdasarkan pengukuran akurat dari prakiraan [[astronomi]] dari putaran bumi. Secara sejarah, satu detik kabisat selalu diperlukan setiap satu atau dua tahun sekali. Namun, detik kabisat sudah lama tidak ditambahkan semenjak tahun 1998, karena perlambatan bumi telah berkurang secara sementara dalam 7 tahun terakhir ini. Detik kabisat yang lalu, seperti pernah diumumkan IERS pada bulan Juli 2005, terjadi pada tanggal 31 Desember 2005.

Untuk keperluan praktis, dan untuk keperluan perdagangan dan hukum, perbedaan kecil (dalam pecahan detik) antara UTC dan UT (atau GMT) adalah dianggap kecil, dan karena alasan ini, dalam percakapan biasa UTC sering disebutkan sebagai GMT, walaupun sebenarnya secara teknis ini adalah tidak tepat.

[[Waktu Indonesia Tangah]] (WITA) adalah sama dengan UTC+8.

== Catatan ==
* {{fnb|1}} WUT dibuat oleh sekelompok ilmuwan internasional, dan mereka tidak mencapai kesepakatan untuk menggunakan singkatan dalam bahasa Inggris, CUT, atau bahasa Prancis, TUC, maka dicarilah jalan tengah yaitu dengan singkatan UTC.<ref>http://tf.nist.gov/general/misc.htm#Anchor-14550.</ref>

== Referensi ==
=== Catatan ===
{{reflist}}

=== Bibilografi ===
{{refbegin|30em}}
* {{Cite book|ref=harv|last1 = Allan|first1=David W.|first2 = Neil|last2 = Ashby|first3 = Clifford C.|last3 = Hodge|publisher = Hewlett-Packard|year = 1997|title = The Science of Timekeeping}} [[Application note|Application Note]].
* {{cite web| ref = harv| last1 = Allen| first1 = Steve| url = http://www.ucolick.org/~sla/leapsecs/utcdoomed| title = UTC is doomed| accessdate = 18 July 2011| year = 2011a}}
* {{cite web | ref = harv | last1 = Allen | first1 = Steve | url = http://www.ucolick.org/~sla/leapsecs/ | title = UTC might be redefined without Leap Seconds | accessdate = 18 July 2011 | year = 2011b }}
* {{Cite conference | ref = harv | conference = ITU-R Special Rapporteur Group Colloquium on the UTC Time Scale | date = 29 May 2003 | url = http://www.ucolick.org/~sla/leapsecs/torino/arias_3.pdf | title = Rotation of the Earth and Time scales | last1 = Arias | first1 = E. F. | last2 = Guinot | first2 = B. | last3 = Quinn | first3 = T. J. }}
* {{cite web | ref = {{SfnRef|Aviation Time|2006}} | title = Aviation Time | year = 2006 | accessdate = 17 July 2011 | publisher = Aircraft Owners and Pilots Association | work = AOPA's Path to Aviation | url = http://www.aopa.org/path/time.html }}
* {{cite web |ref={{SfnRef| Bulletin C| 2011}} |url=http://hpiers.obspm.fr/iers/bul/bulc/bulletinc.dat |title=Bulletin C |publisher=[[International Earth Rotation and Reference Systems Service|IERS EOP PC]], [[Paris Observatory|Observatoire de Paris]] |accessdate=17 July 2011 |date=8 July 2011 }}
* {{cite journal |ref=harv |last=Essen |first=L. |authorlink=Louis Essen |year=1968 |title=Time Scales |journal=Metrologica |volume=4 |issue=4 |pages=161–5 |url=http://www.leapsecond.com/history/1968-Metrologia-v4-n4-Essen.pdf |format=PDF |accessdate=18 October 2008 |doi=10.1088/0026-1394/4/4/003 |bibcode=1968Metro...4..161E }}
* {{cite journal | ref=harv| last1=Finkleman| first1=David| last2=Allen | first2=Steve | last3= Seago | first3 = John | last4 = Seaman | first4 = Rob | last5 = Seidelmann | first5 = P. Kenneth | title = The Future of Time: UTC and the Leap Second | journal=American Scientist | issue = July–August 2011 | year = 2011| page=312 | doi=10.1511/2011.91.1 | arxiv = 1106.3141v1 | volume=99}}
* {{cite journal| ref = harv | last1 = Guinot| first1 = Bernard | date = August 2011 | volume=48 | issue=4 | title = Solar time, legal time, time in use | journal = Metrologica | pages =S181–185| doi = 10.1088/0026-1394/48/4/S08|bibcode = 2011Metro..48S.181G }}
* {{cite web |ref={{SfnRef|History of TAI-UTC|c. 2009}} |url=ftp://maia.usno.navy.mil/ser7/tai-utc.dat |title=History of TAI-UTC |publisher=Time Service Dept., [[United States Naval Observatory|U.S. Naval Observatory]] |accessdate=4 January 2009 |year=c. 2009 |archive-date=19 July 2011 |archive-url=https://web.archive.org/web/20110719193539/http://maia.usno.navy.mil/ser7/tai-utc.dat |dead-url=yes }}
* {{cite web | ref = harv | last1 = Horzepa | first1 = Stan | title = Surfin': Time for Ham Radio | publisher = American Radio Relay League | date = 17 September 2010 | url = http://www.arrl.org/news/surfin-time-for-ham-radio | accessdate = 24 October 2011 }}
* {{cite book|ref=harv|last1=Howse|first1=Derek|title=Greenwich Time and the Longitude|year=1997|publisher=Philip Wilson|location=London|isbn=0-85667-468-0}}
* {{cite web | ref = {{sfnRef|How NTP Works|2011}} | url = http://www.eecis.udel.edu/~mills/ntp/html/warp.html | title = How NTP Works | date = 28 July 2011 | work = NTP: The Network Time Protocol }} See heading "NTP Timescale and Data Formats".
* {{cite web| ref = {{SfnRef|IAU resolutions|1976}}| year = 1976| url = http://www.iau.org/static/resolutions/IAU1976_French.pdf| title = IAU resolutions adopted at the XVIth General Assembly, Grenoble, France, 1976}} Resolution no. 3 by Commissions 4 (Ephemerides/Ephémérides) and 31 (Time/L'Heure) (near the end of the document) "recommend that the following notations be used in all languages", UT0(i), UT1(i), UT2(i), UTC, UTC(i), UT, where (i) is institution "i".
* {{cite web| ref = {{SfnRef|Iceland|2011}}| title = Iceland| year = 2011| url = http://wwp.greenwichmeantime.com/time-zone/europe/iceland/}}
* {{cite journal | ref = {{SfnRef|International Bureau of Weights and Measures|2011}} | author = International Bureau of Weights and Measures | authorlink = International Bureau of Weights and Measures | title = Circular T | issue = 285 | date = 10 October 2011 | url = ftp://ftp2.bipm.org/pub/tai/publication/cirt.285 }}
* {{cite web| ref = harv| author = International Earth Rotation and Reference Systems Service| authorlink = International Earth Rotation and Reference Systems Service| title = IERS Bulletins| date = 19 July 2011| url = http://www.iers.org/IERS/EN/Publications/Bulletins/bulletins.html}}
* {{cite news|last1 = Irvine|first1 = Chris|title = Scientists propose 'leap hour' to fix time system|date = 18 Dec 2008|newspaper = The Telegraph|url = http://www.telegraph.co.uk/science/science-news/3817096/Scientists-propose-leap-hour-to-fix-time-system.html|ref = harv}}
* {{cite web |ref= {{sfnref|ITU Radiocommunication Assembly|2002}} |author= ITU Radiocommunication Assembly |url= http://www.itu.int/dms_pubrec/itu-r/rec/tf/R-REC-TF.460-6-200202-I!!PDF-E.pdf |title= Standard-frequency and time-signal emissions |year= 2002 |publisher= International Telecommunications Union |accessdate= 2 August 2011 }}
* {{cite web|ref=harv|url=http://www.apparent-wind.com/gmt-explained.html|title=A Few Facts Concerning GMT, UT, and the RGO|accessdate=17 July 2011|last1=Langley|first1=Richard B.|date=20 January 1999}}
* {{cite web| ref = {{sfnref|Leap decision postponed|2012}}| url = http://www.bbc.co.uk/news/science-environment-16625614| work = BBC News| title = Leap second decision is postponed| date = January 19, 2012}}
* {{Cite journal |ref=harv |author=McCarthy, Dennis D. |title=Astronomical Time |journal=Proc. IEEE |volume=79 |issue=7 |pages=915–920 |date=July 1991 |doi=10.1109/5.84967 |url=http://www.cl.cam.ac.uk/~mgk25/volatile/astronomical-time.pdf |format=PDF |authorlink=Dennis McCarthy (scientist) }}
* {{Cite book|ref=harv|last1 = McCarthy|first1 = Dennis D.|author1-link = Dennis McCarthy (scientist)|last2 = Seidelmann|first2 = P. Kenneth|year = 2009|publisher = Wiley VCH|location = Weinheim|title = TIME From Earth Rotation to Atomic Physics|isbn = 978-3-527-40780-4}}
* {{cite journal |ref=harv |last=Markowitz |first=W. |coauthors=''et al.'' |year=1958 |month=August |title=Frequency of caesium in terms of Ephemeris Time |journal=Physical Review Letters |volume=1 |issue=3 |pages=105–7 |url=http://www.leapsecond.com/history/1958-PhysRev-v1-n3-Markowitz-Hall-Essen-Parry.pdf |format=PDF |accessdate=18 October 2008 |doi=10.1103/PhysRevLett.1.105 |last2=Hall |first2=R. |last3=Essen |first3=L. |last4=Parry |first4=J. |bibcode=1958PhRvL...1..105M }}
* {{Cite book|ref = harv|year = 1988|last=Markowitz|first = Wm.|editor1-last = Babcock|editor1-first = A. K.|editor2-last = Wilkins|editor2-first = G. A.|title = The Earth's Rotation and Reference Frames for Geodesy and Geophysicss: Proceedings of the 128th Symposium of the International Astronomical Union, held in Coolfont, West Virginia, U.S.A., 20–24 October 1986|chapter = Comparisons of ET(Solar), ET(Lunar), UT and TDT|publisher = Kluwer Academic Publishers|location = Dordrecht|bibcode=1988IAUS..128..413M|pages = 413–418}}
* {{cite web | ref = {{SfnRef|Military & Civilian Time Designations|n.d.}} | url = http://wwp.greenwichmeantime.com/info/timezone.htm | publisher = wwp | title = Military & Civilian Time Designations }}
* {{cite web | ref = harv | author = National Institute of Standards and Technology | authorlink = National Institute of Standards and Technology | accessdate = 17 July 2011 | url = http://www.nist.gov/pml/div688/utcnist.cfm#cut | date = 18 January 2011 | title = Frequently asked questions (FAQ) | archive-date = 24 March 2015 | archive-url = https://web.archive.org/web/20150324013728/http://www.nist.gov/pml/div688/utcnist.cfm#cut | dead-url = yes }}
* {{cite web | ref = harv | author = National Institute of Standards and Technology | authorlink = National Institute of Standards and Technology | url = http://www.nist.gov/pml/div688/leapseconds.cfm#often | date = 19 March 2012 | title = Frequently asked questions (FAQ) | access-date = 7 July 2020 | archive-date = 7 April 2016 | archive-url = https://web.archive.org/web/20160407135200/http://www.nist.gov/pml/div688/leapseconds.cfm#often | dead-url = yes }}
* {{cite web | ref = {{SfnRef|Military and Civilian Time Zones |n.d.}} | url = http://www.timehubzone.com/time/zones | publisher = www.timehubzone.com | title = Military and Civilian Time Zones }}
* {{cite web |ref=harv |last1=Nelson |first1=G.K. |last2=Lombardi |first2=M.A. |last3=Okayama |first3=D.T. |title=NIST Time and Frequency Radio Stations: WWV, WWVH, and WWVB |year=2005 |work= |publisher=[[National Institute of Standards and Technology]] |url=http://ts.nist.gov/MeasurementServices/Calibrations/upload/SP250-67.pdf |format=PDF |id=(Special Publication 250-67) |access-date=2020-07-07 |archive-date=2011-09-27 |archive-url=https://web.archive.org/web/20110927045207/http://ts.nist.gov/MeasurementServices/Calibrations/upload/SP250-67.pdf |dead-url=yes }}
* {{Cite conference | ref = harv | last1 = Nelson | first1 = Robert A. | last2 = McCarthy | first2 = Dennis D. | author2-link = Dennis McCarthy (scientist) | url = http://www.navcen.uscg.gov/pdf/cgsicMeetings/45/29a%20UTCLeapSecond.ppt | title = Coordinated Universal Time (UTC) and the Future of the Leap Second | conference = Civil GPS Interface Committee | publisher = [[United States Coast Guard]] | date = 13 September 2005 | access-date = 7 July 2020 | archive-date = 30 January 2012 | archive-url = https://web.archive.org/web/20120130220042/http://www.navcen.uscg.gov/pdf/cgsicMeetings/45/29a%20UTCLeapSecond.ppt | dead-url = yes }}
* {{Cite journal |ref=harv |last1=Nelson |first1=Robert A. |last2=McCarthy |first2=Dennis D. |coauthors=''et al.'' |title=The leap second: its history and possible future |journal=Metrologia |volume=38 |issue=6 |pages=509–529 |year=2001 |format=PDF |doi=10.1088/0026-1394/38/6/6 |url=http://www.cl.cam.ac.uk/~mgk25/time/metrologia-leapsecond.pdf |bibcode=2001Metro..38..509N }}
* {{cite journal | ref = harv | last1 = Seidelmann | first1 = P. Kenneth | last2 = Seago | first2 = John H. | date = August 2011 | volume = 48 | issue = 4 | title = Time scales, their users, and leap seconds | journal = Metrologia | pages = S186–S194 | url = http://www.agi.com/resources/user-resources/downloads/white-paper.aspx?id=158 | doi = 10.1088/0026-1394/48/4/S09 | bibcode = 2011Metro..48S.186S | access-date = 2020-07-07 | archive-date = 2012-10-19 | archive-url = https://web.archive.org/web/20121019144359/http://www.agi.com/resources/user-resources/downloads/white-paper.aspx?id=158 | dead-url = yes }}
* {{cite web | ref = harv | last1 = Seaman | first1 = Rob | url = http://iraf.noao.edu/~seaman/leap/ | title = A Proposal to Upgrade UTC | accessdate = 18 July 2011 | year = 2003 | archive-date = 23 July 2011 | archive-url = https://web.archive.org/web/20110723140249/http://iraf.noao.edu/~seaman/leap/ | dead-url = yes }}
* {{Cite book|ref=harv|last=Seidelmann|first=P.K.|title=Explanatory Supplement to the Astronomical Almanac|publisher=University Science Books|location=Sausalito, CA|year=1992}}
* {{Cite journal | ref = harv | last1 = Stephenson | first1 = F. R. | last2 = Morrison | first2 = L. V. |title=Long-term fluctuations in the Earth's rotation: 700 BC to AD 1990 | journal = Philosophical Transactions of the Royal Society A | year = 1995 | pages = 165–202 | bibcode = 1995RSPTA.351..165S | volume = 351 | doi = 10.1098/rsta.1995.0028 | issue = 1695}}
* {{cite web | ref = {{sfnref|Standard time|2010}} | title = Standard time | year = 2010 | url = http://www.law.cornell.edu/uscode/html/uscode15/usc_sup_01_15_10_6_20_IX.html | work = U.S. Code | publisher = Legal Information Institute }} Title 15, Chapter 6, Subchapter IX.
* {{cite web | ref = harv | url = http://www.cl.cam.ac.uk/~mgk25/volatile/ITU-R-TF.460-4.pdf | title = TF.460-4: Standard-frequency and time-signal emissions | publisher = International Telecommunication Union | at = Annex I | year = 1986 }}
* {{cite web |ref = {{sfnRef|Time|n.d.}} |url = http://www.bipm.org/en/scientific/tai/ |date = n.d. |accessdate = 22 May 2013 |publisher = International Bureau of Weights and Measures |title = Time }}
* {{cite web | ref = harv | author = Time Service Dept. | title = Leap Seconds | year = c. 2009 | publisher = United States Naval Observatory | url = http://tycho.usno.navy.mil/leapsec.html | accessdate = 17 July 2011 | archive-date = 26 November 1996 | archive-url = https://web.archive.org/web/19961126204059/http://tycho.usno.navy.mil/leapsec.html | dead-url = yes }}
* {{cite web| ref = {{SfnRef|United States Naval Observatory|n.d.}}| accessdate = 10 Oct 2013| title = Universal Time| author = United States Naval Observatory| url = http://aa.usno.navy.mil/faq/docs/UT.php| archive-date = 22 July 2011| archive-url = https://web.archive.org/web/20110722212121/http://aa.usno.navy.mil/faq/docs/UT.php| dead-url = yes}}
* {{cite web | title = Universal Time | work = Oxford Dictionaries: British and World English | accessdate = 9 March 2013 | url = http://oxforddictionaries.com/definition/english/Universal%2BTime | publisher = Oxford University Press | ref = {{SfnRef|Universal Time|n.d.}} | archive-date = 4 May 2013 | archive-url = https://web.archive.org/web/20130504193834/http://oxforddictionaries.com/definition/english/Universal%2BTime | dead-url = yes }}
* {{cite news|ref=harv|first=Jack|last=Williams|title=Understanding and using Zulu time|url=http://www.usatoday.com/weather/zulu.htm|work=|publisher=[[USA Today]]|date=17 May 2005|accessdate=25 February 2007}}
{{refend}}

== Lihat pula ==
* [[Waktu Atom Internasional]] ([[Waktu Atom Internasional|TAI]])
* [[Universal Time|Waktu Universal]] ([[Universal Time]]) juga termasuk definisi UT1
* [[Waktu Sidereal]] ([[Waktu Sidereal|Sidereal Time]])
* [[Waktu Ephemeris]] ([[Waktu Ephemeris|Ephemeris Time]])
* [[Waktu Matahari]]
* [[Jam atom]]

== Pranala luar ==
{{Wiktionary|UTC}}
* [http://www.cl.cam.ac.uk/~mgk25/time/zeitgesetz.en.html Definition of Coordinated Universal Time in German law–ZeitG §1 (3)]
* [http://hpiers.obspm.fr/eop-pc/earthor/utc/TAI-UTC_tab.html International Earth Rotation Service; list of differences between TAI and UTC from 1961 to present]
* [http://www.usno.navy.mil/USNO/time/master-clock/systems-of-time U.S. Naval Observatory: Systems of Time] {{Webarchive|url=https://web.archive.org/web/20141011153200/http://www.usno.navy.mil/USNO/time/master-clock/systems-of-time |date=2014-10-11 }}
* [http://www.w3.org/TR/NOTE-datetime W3C Specification about UTC Date and Time] and [[IETF]] [[Internet standard]] RFC 3339, based on [[ISO 8601]]
* [http://www.ipses.com/prod/timing/UTC-GPS.php?language=en Standard of time definition: UTC, GPS, LORAN and TAI]
* [https://itunews.itu.int/En/4271-What-is-in-a-nameBROn-the-term-Coordinated-Universal-Time.note.aspx What is in a name? On the term Coordinated Universal Time]
{{Perbedaan waktu UTC}}

[[Kategori:Sistem koordinat langit]]

[[fi:Aikajärjestelmä#UTC]]