2113:
is to be measured—happen to be in a straight line for both measures. However, for the first measurement, the Earth is between the Sun and the targeted object, and for the second, the Earth is on the opposite side of the Sun from that object. Then, the two measurements would differ by about 1000 light-seconds: For the first measurement, the Earth is roughly 500 light seconds closer to the target than the Sun, and roughly 500 light seconds further from the target astronomical object than the Sun for the second measure. An error of about 1000 light-seconds is over 1% of a light-day, which can be a significant error when measuring temporal phenomena for short period astronomical objects over long time intervals. To clarify this issue, the ordinary Julian day is sometimes referred to as the
Geocentric Julian Day (GJD) in order to distinguish it from HJD.
4328:
200:. For example, if a given "Julian date" is "October 5, 1582", this means that date in the Julian calendar (which was October 15, 1582, in the Gregorian calendar—the date it was first established). Without an astronomical or historical context, a "Julian date" given as "36" most likely means the 36th day of a given Gregorian year, namely February 5. Other possible meanings of a "Julian date" of "36" include an astronomical Julian Day Number, or the year AD 36 in the Julian calendar, or a duration of 36 astronomical
657:
recycled to zero on MJD 50000, or
October 10, 1995, "which gives a long ambiguity period of 27.4 years". (NASA codes PB-1–PB-4 used a 3-digit day-of-year count.) Only whole days are represented. Time of day is expressed by a count of seconds of a day, plus optional milliseconds, microseconds and nanoseconds in separate fields. Later PB-5J was introduced which increased the TJD field to 16 bits, allowing values up to 65535, which will occur in the year 2147. There are five digits recorded after TJD 9999.
1064:, and the noon of January 1 of that year, for the meridian of Alexandria, is the chronological epoch, to which all historical eras are most readily and intelligibly referred, by computing the number of integer days intervening between that epoch and the noon (for Alexandria) of the day, which is reckoned to be the first of the particular era in question. The meridian of Alexandria is chosen as that to which Ptolemy refers the commencement of the era of Nabonassar, the basis of all his calculations.
4322:
243:(UTC) and that the scale should be indicated when the difference is significant. The fraction of the day is found by converting the number of hours, minutes, and seconds after noon into the equivalent decimal fraction. Time intervals calculated from differences of Julian Dates specified in non-uniform time scales, such as UTC, may need to be corrected for changes in time scales (e.g.
1229:
discussion, but no name was used in the tables. Continuing this tradition, in his book "Mapping Time: The
Calendar and Its History" British physics educator and programmer Edward Graham Richards uses Julian day numbers to convert dates from one calendar into another using algorithms rather than tables.
2112:
To illustrate the ambiguity that could arise from conflating
Heliocentric time and Terrestrial time, consider the two separate astronomical measurements of an astronomical object from the Earth: Assume that three objects—the Earth, the Sun, and the astronomical object targeted, that is whose distance
695:
is a count of days of the
Gregorian calendar and not defined relative to the Julian Date. It is an integer applied to a whole day; day 1 was October 15, 1582, which was the day the Gregorian calendar went into effect. The original paper defining it makes no mention of the time zone, and no mention of
1397:
1059:
The period thus arising of 7980 Julian years, is called the Julian period, and it has been found so useful, that the most competent authorities have not hesitated to declare that, through its employment, light and order were first introduced into chronology. We owe its invention or revival to Joseph
267:
refers to the point in time used to set the origin (usually zero, but (1) where explicitly indicated) of the alternative convention being discussed in that row. The date given is a
Gregorian calendar date unless otherwise specified. JD stands for Julian Date. 0h is 00:00 midnight, 12h is 12:00 noon,
1228:
containing over 530,000 Julian days, one for the zeroth day of every month over thousands of years in many calendars. He included over 25,000 negative Julian days, given in a positive form by adding 10,000,000 to each. He called them "day of the Julian Period", "Julian day", or simply "day" in his
1120:
was the last to add a multi-year table, in 1925 with 2,000 years. However, it was the first to include any mention of Julian days with one for the year of issue beginning in 1855, as well as later scattered sections with many days in the year of issue. It was also the first to use the name "Julian
1173:
chose to begin the days for his astronomical observations at noon. He chose noon because the transit of the Sun across the observer's meridian occurs at the same apparent time every day of the year, unlike sunrise or sunset, which vary by several hours. Midnight was not even considered because it
1096:
west of
Washington (282°57′W, or Washington 77°3′W of Greenwich). A table with 197 Julian days ("Date in Mean Solar Days", one per century mostly) was included for the years –4713 to 2000 with no year 0, thus "–" means BC, including decimal fractions for hours, minutes and seconds. The same table
656:
in 1979 as part of a parallel grouped binary time code (PB-5) "designed specifically, although not exclusively, for spacecraft applications". TJD was a 4-digit day count from MJD 40000, which was May 24, 1968, represented as a 14-bit binary number. Since this code was limited to four digits, TJD
259:
is so long ago, numbers in the Julian day can be quite large and cumbersome. A more recent starting point is sometimes used, for instance by dropping the leading digits, in order to fit into limited computer memory with an adequate amount of precision. In the following table, times are given in
1973:
As stated above, the Julian date (JD) of any instant is the Julian day number for the preceding noon in
Universal Time plus the fraction of the day since that instant. Ordinarily calculating the fractional portion of the JD is straightforward; the number of seconds that have elapsed in the day
1186:
days beginning at sunset. Medieval Muslim astronomers used days beginning at sunset, so astronomical days beginning at noon did produce a single date for an entire night. Later medieval
European astronomers used Roman days beginning at midnight so astronomical days beginning at noon also allow
810:
Scaliger corrected chronology by assigning each year a tricyclic "character", three numbers indicating that year's position in the 28-year solar cycle, the 19-year lunar cycle, and the 15-year indiction cycle. One or more of these numbers often appeared in the historical record alongside other
1417:
Because a Julian day starts at noon while a civil day starts at midnight, the Julian day number needs to be adjusted to find the day of week: for a point in time in a given Julian day after midnight UT and before 12:00 UT, add 1 or use the JDN of the next afternoon.
970:, began in sequence. Although not their intended use, the equations of de Billy or Gauss can be used to determined the first year of any 15-, 19-, and 28-year tricyclic period given any first years of their cycles. For those of the Julian Period, the result is AD
157:
is the Julian day number plus the fraction of a day since the preceding noon in
Universal Time. Julian dates are expressed as a Julian day number with a decimal fraction added. For example, the Julian Date for 00:30:00.0 UT January 1, 2013, is
1194:
During this period, usage of Julian day numbers as a neutral intermediary when converting a date in one calendar into a date in another calendar also occurred. An isolated use was by Ebenezer Burgess in his 1860 translation of the
827:
with 19 solar cycles (each of 28 years, each year numbered 1–28) and 28 lunar cycles (each of 19 years, each year numbered 1–19), he determined that the first two numbers, 9 and 1, occurred at its year 457. He then calculated via
1303:
953:
The specific cycles used by Scaliger to form his tricyclic Julian Period were, first, the indiction cycle with a first year of 313. Then he chose the dominant 19-year Alexandrian lunar cycle with a first year of 285, the
811:
pertinent facts without any mention of the Julian calendar year. The character of every year in the historical record was unique – it could only belong to one year in the 7980-year Julian Period. Scaliger determined that
204:). This is why the terms "ordinal date" or "day-of-year" are preferred. In contexts where a "Julian date" means simply an ordinal date, calendars of a Gregorian year with formatting for ordinal dates are often called
997:
BC, the Byzantine Creation. Dionysius Exiguus called the Byzantine lunar cycle his "lunar cycle" in argumentum 6, in contrast with the Alexandrian lunar cycle which he called his "nineteen-year cycle" in argumentum 5.
2091:−4712, etc.). In this article, dates before October 15, 1582, are in the (possibly proleptic) Julian calendar and dates on or after October 15, 1582, are in the Gregorian calendar, unless otherwise labelled.
1594:, to a date in the Gregorian calendar (proleptic, when applicable). Richards states the algorithm is valid for Julian day numbers greater than or equal to 0. All variables are integer values, and the notation "
1060:
Scaliger, who is said to have received it from the Greeks of Constantinople. The first year of the current Julian period, or that of which the number in each of the three subordinate cycles is 1, was the year
93:. Historians used the period to identify Julian calendar years within which an event occurred when no such year was given in the historical record, or when the year given by previous historians was incorrect.
1982:(SOFA), deals with this issue by treating days containing a leap second as having a different length (86,401 or 86,399 seconds, as required). SOFA refers to the result of such a calculation as "quasi-JD".
946:
described the details of how these three numbers were calculated in 1666, using many trials. A summary of Collin's description is in a footnote. Reese, Everett and Craun reduced the dividends in the
3065:
L. E. Doggett, Ch. 12, "Calendars", p. 604, in Seidelmann 1992. "These algorithms are valid for all Gregorian calendar dates corresponding to JD >= 0, i.e, dates after −4713 November 23."
645:, using 63-bit date/time, which allows times to be stored up to July 31, 31086, 02:48:05.47. The MJD has a starting point of midnight on November 17, 1858, and is computed by MJD = JD − 2400000.5
989:. Specifically, the monk and priest Georgios wrote in 638/39 that the Byzantine year 6149 AM (640/41) had indiction 14, lunar cycle 12, and solar cycle 17, which places the first year of the
4226:
4149:
1187:
observations during an entire night to use a single date. When all astronomers decided to start their astronomical days at midnight to conform to the beginning of the civil day, on
3571:
2087:(which has no year 0 between 1 BC and AD 1). Astronomical calculations generally include a year 0, so these dates should be adjusted accordingly (i.e. the year 4713 BC becomes
1944:
Let Y be the year BC or AD and i, m and s respectively its positions in the indiction, Metonic and solar cycles. Divide 6916i + 4200m + 4845s by 7980 and call the remainder r.
799:
Its epoch occurs when all three cycles (if they are continued backward far enough) were in their first year together. Years of the Julian Period are counted from this year,
1104:
The national ephemerides started to include a multi-year table of Julian days, under various names, for either every year or every leap year beginning with the French
853:
4096:
3823:
2386:
The value of this property represents the number of 100-nanosecond intervals that have elapsed since 12:00:00 midnight, January 1, 0001 in the Gregorian calendar,
3306:
1392:{\displaystyle {\begin{matrix}J\!D&=&J\!D\!N+{\frac {{\text{hour}}-12}{24}}+{\frac {\text{minute}}{1440}}+{\frac {\text{second}}{86400}}\end{matrix}}}
4142:
1146:
observations, thus eliminating the complications resulting from using standard calendar periods like eras, years, or months. They were first introduced into
781:, a classical scholar, in 1583 (one year after the Gregorian calendar reform) as it is the product of three calendar cycles used with the Julian calendar:
1142:, in 1823. Other astronomers added fractions of the day to the Julian day number to create Julian Dates, which are typically used by astronomers to date
3194:
4680:
3968:
4135:
4039:
2507:
2144:
Doggett in Seidenmann 1992, p. 603, indicates the algorithms are inspired by Fliegel & Van Flanderen 1968. That paper gives algorithms in
4006:
3899:
3748:
3741:
3713:
3675:
3643:
3377:
3297:
2884:
The Nabonassar day was elapsed with a typo – it was correctly printed later as 1448638. The Christian day (1721425) was current, not elapsed.
362:
4649:
3183:
680:, 1900, which is the same as noon UT on December 31, 1899. The DJD was defined by the International Astronomical Union at their meeting in
2398:
3720:
747:, and thus can differ from the Julian day by as much as 8.3 minutes (498 seconds), that being the time it takes light to reach
1271:
JDN = (1461 × (Y + 4800 + (M − 14)/12))/4 +(367 × (M − 2 − 12 × ((M − 14)/12)))/12 − (3 × ((Y + 4900 + (M - 14)/12)/100))/4 + D − 32075
3913:
4400:
4065:
3991:
3840:
3770:
3660:
3545:
3231:
3212:
3165:
3972:
985:
Scaliger got the idea of using a tricyclic period from "the Greeks of Constantinople" as Herschel stated in his quotation below in
2148:. The Fortran computer language performs integer division by truncating, which is functionally equivalent to rounding toward zero.
220:
3317:
847:
A formula for determining the year of the Julian Period given its character involving three four-digit numbers was published by
3604:
3413:
4911:
4473:
3615:
2355:
1978:
contains 86,401 seconds (or in the unlikely event of a negative leap second, 86,399 seconds). One authoritative source, the
665:
1283:) Julian calendar years ≥ −4712, that is, for all JDN ≥ 0. Divisions are integer divisions, fractional parts are ignored.
4654:
2403:
2341:
1241:
rounding towards zero is used exclusively, that is, positive values are rounded down and negative values are rounded up):
1209:
at the end of the 588,465th day and the beginning of the 588,466th day (civil reckoning) of the Julian Period, or between
715:
2215:"Astronomical Almanac Online" 2016, Glossary, s.v. Julian date. Various timescales may be used with Julian date, such as
4916:
4906:
1261:
943:
731:
608:
495:
113:
1974:
divided by the number of seconds in a day, 86,400. But if the UTC timescale is being used, a day containing a positive
4609:
4589:
4535:
4420:
4256:
3997:
Seidelmann, P. Kenneth. (2013). "Introduction to Positional Astronomy" in Sean Urban and P. Kenneth Seidelmann (eds.)
3726:
3631:
2088:
1252:
is the Julian Day Number. Use the previous day of the month if trying to find the JDN of an instant before midday UT.
1245:
1159:
653:
236:
1936:
are the numbers of the day, month, and year respectively for the afternoon at the beginning of the given Julian day.
823:
had the character 9 of the solar cycle, 1 of the lunar cycle, and 3 of the indiction cycle. By inspecting a 532-year
3424:, Her Majesty's Stationery Office, 1961, pp. 21, 71, 97, 100, 264, 351, 365, 376, 386–9, 392, 431, 437–41, 489.
2103:
This is an epoch starting with day 1 instead of 0. Conventions vary as to whether this is based on UT or local time.
4926:
4276:
4261:
4199:
4178:
3303:
3216:
3175:
3157:
1505:
If the moment in time is after midnight UT (and before 12:00 UT), then one is already in the next day of the week.
240:
173:
4430:
4241:
4072:
1280:
1224:. Here he used about 5,370 "days of the Julian Period". He greatly expanded his usage of Julian days in his 1908
950:
column from 285, 420, 532 to 5, 2, 7 and changed remainder to modulo, but apparently still required many trials.
711:
311:
228:
109:
1023:", which Reese, Everett and Craun translate as "We have termed it Julian because it fits the Julian year." Thus
3469:
Grafton, Anthony T. (May 1975) "Joseph Scaliger and historical chronology: The rise and fall of a discipline",
3368:
1155:
962:. Finally, Scaliger chose the post-Bedan solar cycle with a first year of 776, when its first quadrennium of
4690:
4468:
4370:
4286:
4281:
2860:
Scaliger used these words in his 1629 edition on p. 361 and in his 1598 edition on p. 339. In 1583 he used "
1997:
1040:
740:
641:(36-bit machine) and using only 18 bits until August 7, 2576. MJD is the epoch of VAX/VMS and its successor
201:
50:
660:
The Dublin Julian Date (DJD) is the number of days that has elapsed since the epoch of the solar and lunar
3384:
2059:
2033:
2017:
1179:
1006:
785:
778:
286:
256:
196:, especially in computer programming, the military and the food industry, or it may refer to dates in the
121:
2277:
4843:
3259:
3947:
Denkschriften der Kaiserlichen Akademie der Wissenschaften, Mathematisch-Naturwissenschafteliche Classe
3497:
3133:
3716:. Page references in text, footnotes, and index are six greater than the page numbers in this edition.
1154:, which he stated was at the suggestion of John Herschel. They were popularized for variable stars by
4670:
4584:
4410:
4271:
3785:
1133:
903:
70:
for easily calculating elapsed days between two events (e.g. food production date and sell by date).
3722:
Metadata Issues in the EOSDIS Science Data Processing Tools for Time Transformations and Geolocation
3421:
Explanatory Supplement to the Astronomical Ephemeris and the American Ephemeris and Nautical Almanac
2369:
978:
years must be subtracted from it to yield the first year of the present Julian Period, −4712 or 4713
832:
that he needed to add eight 532-year Paschal cycles totaling 4256 years before the cycle containing
4921:
4880:
4675:
4530:
4395:
4347:
4216:
3856:
3402:
3327:
963:
685:
517:
212:
62:
is the continuous count of days since the beginning of the Julian period, and is used primarily by
43:
3867:"The origin of the Julian Period: An application of congruences and the Chinese Remainder Theorem"
3559:
4855:
4629:
4553:
4483:
3477:
1615:
1439:
1077:
633:(MJD) was introduced by the Smithsonian Astrophysical Observatory in 1957 to record the orbit of
481:
193:
4050:
1092:
from 1855 to 1888. The days are specified for "Washington mean noon", with Greenwich defined as
3262:(NASA Technical Memorandum 80606). Retrieved from NASA Technical Reports Server April 24, 2015.
2482:
2409:
89:
year 2024 is year 6737 of the current Julian Period. The next Julian Period begins in the year
4703:
4568:
4385:
4090:
4061:
4002:
3987:
3942:
3920:
3909:
3895:
3836:
3817:
3766:
3737:
3709:
3671:
3656:
3639:
3541:
3506:
3373:
3359:
3293:
3227:
3208:
3179:
3161:
2012:
1992:
959:
100:(JDN) is the integer assigned to a whole solar day in the Julian day count starting from noon
4019:
3982:
2030:– the epoch that starts on JD 2451545.0 (TT), the standard epoch used in astronomy since 1984
1294:
For the full Julian Date of a moment after 12:00 UT one can use the following. Divisions are
4848:
4594:
4573:
4525:
4488:
4301:
3931:
3793:
3776:
Pogson, Norman R. (1860), "Notes on certain variable stars of unknown or doubtful periods",
3622:
3523:
3517:
3458:
2216:
1979:
1603:
1238:
1166:
974:
3268, because both remainder and modulo usually return the lowest positive result. Thus 7980
907:
848:
829:
232:
224:
129:
3880:
1959:(6916 × 8) = 55328; (4200 × 2) = 8400: (4845 × 8) = 38760. 55328 + 8400 + 38760 = 102488.
1191:, it was decided to keep Julian days continuous with previous practice, beginning at noon.
1136:
first expressed the time of day as a decimal fraction added to calendar dates in his book,
4579:
4558:
4390:
4362:
4029:
3701:
3608:
3363:
3310:
3198:
2038:
1197:
1073:
1028:
697:
669:
208:, but this could also mean that the calendars are of years in the Julian calendar system.
197:
86:
31:
4080:
3807:
3959:
3789:
4875:
4634:
4624:
4563:
4520:
4352:
4342:
4311:
4211:
4183:
3493:
955:
719:
216:
133:
101:
3419:
3385:"Der Mönch und Presbyter Georgios, ein unbekannter Schriftsteller des 7. Jahrhunderts"
104:, with Julian day number 0 assigned to the day starting at noon on Monday, January 1,
4900:
4762:
4713:
4698:
4644:
4415:
4251:
4246:
4162:
2054:
1147:
1048:
990:
858:
824:
789:
723:
125:
3339:"A problem for finding the year of the Julian Period by a new and very easie method"
3304:"CS 1063 Introduction to Programming: Explanation of Julian Day Number Calculation."
2280:
of the XXIIIrd International Astronomical Union General Assembly, Kyoto, Japan, 1997
188:
may also refer, outside of astronomy, to the day-of-year number (more properly, the
4860:
4747:
4742:
4737:
4724:
4463:
3599:
3528:
3428:
2044:
2007:
1151:
743:(HJD) is the same as the Julian day, but adjusted to the frame of reference of the
189:
39:
35:
3693:
3581:
3395:
3280:
3253:
3148:
2122:
All years in this paragraph are those of the Anno Domini Era at the time of Easter
4127:
3862:, "Dates and the Gregorian calendar" pages 106–111. Retrieved September 10, 2009.
3756:
3533:. Herschel's words remained the same in all editions, even while the page varied.
3439:
3201:. (2016). U.S. Nautical Almanac Office and Her Majesty's Nautical Almanac Office.
4870:
4865:
4510:
4493:
4425:
4405:
4291:
4173:
2080:
2002:
1975:
1295:
1175:
692:
661:
464:
244:
3890:
Richards, E. G. (2013). Calendars. In S. E. Urban & P. K. Seidelmann, eds.
2219:(TT) or Universal Time (UT); in precise work the timescale should be specified.
1590:
This is an algorithm by Edward Graham Richards to convert a Julian Day Number,
4885:
4838:
4822:
4708:
4435:
4296:
4266:
4204:
3734:
Scandalous Error: Calendar Reform and Calendrical Astronomy in Medieval Europe
3648:
2084:
1428:(for an afternoon or evening UT) can be determined from the Julian Day Number
1125:
began in 1866 to include a Julian day for every day in the year of issue. The
1069:
727:
722:, others use local time. Day 1 is January 1, 1, that is, the first day of the
510:
78:
63:
3894:, 3rd ed. (pp. 585–624). Mill Valley, Calif.: University Science Books.
3798:
4782:
4619:
4503:
4478:
4458:
4375:
4327:
4321:
4306:
3638:, 3rd ed. (pp. 76–104). Mill Valley, Calif.: University Science Books.
3267:"A method for finding the number of the Julian Period for any year assign'd"
2373:
1202:
1183:
1143:
1085:
793:
677:
634:
622:
Count of 100-nanosecond ticks, excluding ticks attributable to leap seconds
600:
538:
117:
4112:
3634:& Guinot, B. (2013). Time. In S. E. Urban & P. K. Seidelmann, eds.
3149:
American Ephemeris and Nautical Almanac, Washington, 1855–1980, Hathi Trust
17:
4001:(3rd ed.) pp. 1–44. Mill Valley, CA: University Science Books.
1286:
JDN = 367 × Y − (7 × (Y + 5001 + (M − 9)/7))/4 + (275 × M)/9 + D + 1729777
1129:
began in 1871 to include a Julian day for every day in the year of issue.
4817:
4797:
4639:
4545:
4445:
4236:
4231:
3835:, translated by Gingerich, Owen, Princeton University Press, p. 12,
703:
488:
67:
3313:(2011). Computer Science Department, University of Texas at San Antonio.
1108:
in 1870 for 2,620 years, increasing in 1899 to 3,000 years. The British
4812:
4802:
4732:
4604:
4515:
4380:
4012:
3481:
3029:
Burgess was furnished these Julian days by US Nautical Alamanac Office.
2145:
1170:
642:
638:
154:
105:
1237:
The Julian day number can be calculated using the following formulas (
1178:. Nevertheless, he double-dated most nighttime observations with both
1165:
Julian days begin at noon because when Herschel recommended them, the
4807:
4757:
4752:
3611:(March 20, 2013). US Naval Observatory. Retrieved September 16, 2013.
3338:
3266:
3238:
1206:
1084:, begun in 1849 but not published until 1853, to calculate the lunar
881:, by 6916. Then divide the Sum of the products by 7980, which is the
681:
3683:
Moyer, Gordon. (April 1981). "The Origin of the Julian Day System",
3589:
3550:
2356:"2. Data Structures and Algorithms — the Linux Kernel documentation"
1043:
for the first days of the Nabonassar and Christian eras in his 1825
30:"Julian date" redirects here. For dates in the Julian calendar, see
1244:
The months January to December are numbered 1 to 12. For the year,
861:
gave the same formula using slightly different wording in his 1849
132:. For example, the Julian day number for the day starting at 12:00
4787:
4599:
4498:
4453:
3866:
3427:
Fliegel, Henry F. & Van Flanderen, Thomas C. (October 1968). "
2863:
Iulianam vocauimus: quia ad annum Iulianum duntaxat accomodata est
2399:"38 Why Is Wednesday November 17, 1858 The Base Time For VAX/VMS?"
2027:
958:
and the Diocletian Era epoch, or a first year of 532 according to
748:
457:
440:
1169:
began at noon. The astronomical day had begun at noon ever since
4792:
4777:
4767:
4221:
4158:
3865:
Reese, Ronald Lane; Everett, Steven M.; Craun, Edwin D. (1981).
3488:
Joseph Scaliger: A Study in the History of Classical Scholarship
3260:"A Grouped Binary Time Code for Telemetry and Space Application"
3254:
Berliner astronomisches Jahrbuch, Berlin, 1776–1922, Hathi Trust
2757:
2755:
2049:
1422:
1401:
So, for example, January 1, 2000, at 18:00:00 UT corresponds to
707:
649:
578:
433:
416:
385:
116:), a date at which three multi-year cycles started (which are:
4131:
3396:
Why is Wednesday, November 17, 1858, the base time for VAX/VMS?
1405:= 2451545.25 and January 1, 2000, at 6:00:00 UT corresponds to
982:
BC, when all three of its sub-cycles are in their first years.
4772:
3618:. Goddard Earth Sciences Data and Information Services Center.
3567:
3074:
L. E. Doggett, Ch. 12, "Calendars", p. 606, in Seidelmann 1992
2022:
752:
744:
408:
271:
3447:
Gauss, Carl Frederich (1966). Clarke, Arthur A., translator.
2787:
2785:
2131:
The concurrent of any Julian year is the weekday of its March
3887:(Kyoto, Japan). International Astronomical Union, p. 7.
3490:. Volume II: Historical Chronology (Oxford-Warburg Studies).
3189:
1264:) Gregorian calendar dates after November 23, −4713.
1072:
adopted Herschel's "days of the Julian period" immediately.
2179:
p. B4, which states 2017 is year 6730 of the Julian Period.
1290:
Finding Julian date given Julian day number and time of day
1248:
is used, thus 1 BC is 0, 2 BC is −1, and 4713 BC is −4712.
4227:
International Earth Rotation and Reference Systems Service
3858:
ASTROCLK Astronomical Clock and Celestial Tracking Program
3749:
Computer processing of dates outside the twentieth century
3508:
Astronomia accurata; or the royal astronomer and navigator
227:. Seidelmann indicates that Julian dates may be used with
4056:
US Naval Observatory. (2005, last updated July 2, 2011).
3433:
Communications of the Association for Computing Machinery
2498:
Dershowitz & Reingold 2008, 10, 351, 353, Appendix B.
3668:
The Easter Computus and the Origins of the Christian Era
3444:
Boston: Houghton-Mifflin. Vassar Semi-Centennial Series.
2829:
2827:
176:) – expressed as a Julian date this is 2460577.3389005.
81:
interval of 7980 years; year 1 of the Julian Period was
3561:
Handbuch der mathematischen und technischen Chronologie
1256:
Converting Gregorian calendar date to Julian Day Number
1045:
Handbuch der mathematischen und technischen Chronologie
807:, which was chosen to be before any historical record.
270:
Current value is at 20:08, Monday, September 23, 2024 (
38:. For the comic book character Julian Gregory Day, see
3540:, p. 257, Springer Science & Business Media,
3222:
Blackburn, Bonnie; Holford-Strevens, Leofranc. (1999)
1940:
Julian Period from indiction, Metonic and solar cycles
1308:
294:
4015:". (June 14, 2016). International Astronomical Union.
3451:. Article 36. pp. 16–17. Yale University Press.
3354:
The bulletin of the American Society of Papyrologists
3292:, tr. Michael Whitby, Mary Whitby, 1989, p. 10,
2483:"datetime — Basic date and time types — date Objects"
1306:
1051:
then developed them for astronomical use in his 1849
1020:
Iulianam vocauimus: quia ad annum Iulianum accomodata
836:
in order for its year 457 to be indiction 3. The sum
211:
Historically, Julian dates were recorded relative to
1275:
Converting Julian calendar date to Julian Day Number
1220:. Robert Schram was notable beginning with his 1882
4831:
4722:
4689:
4663:
4544:
4444:
4361:
4335:
4192:
3999:
Explanatory supplement to the Astronomical Almanac'
3594:
Defit's Definitions of Information Technology Terms
3586:. (January 1998). International Astronomical Union.
3538:
Using Commercial Amateur Astronomical Spectrographs
3352:
Leo Depuydt, "AD 297 as the first indiction cycle",
1586:
Julian or Gregorian calendar from Julian day number
3986:pages 55 & 603–606. University Science Books,
3983:Explanatory Supplement to the Astronomical Almanac
3892:Explanatory Supplement to the Astronomical Almanac
3708:, Red Sea Press, 2016, pp. 22, 93, 111, 183,
3636:Explanatory Supplement to the Astronomical Almanac
1391:
1101:by Joseph Winlock, without any other Julian days.
223:has recommended that Julian dates be specified in
172:. This article was loaded at 2024-09-23 20:08:01 (
4075:. US Naval Observatory. Retrieved April 24, 2015.
3778:Monthly Notices of the Royal Astronomical Society
3736:, Oxford University Press, 2018, pp. 57–58,
3572:"CEEDATE—convert Lilian date to character format"
3429:A machine algorithm for processing calendar dates
1332:
1328:
1314:
1055:, after acknowledging that Ideler was his guide.
700:, the principal author of the Gregorian calendar.
648:The Truncated Julian Day (TJD) was introduced by
4058:Multiyear Interactive Computer Almanac 1800–2050
3207:, tr. Faith Wallis, 725/1999, pp. 392–404,
3119:"SOFA Time Scale and Calendar Tools" 2016, p. 20
2408:. Colorado Springs. June 6, 2007. Archived from
1005:in "Julian Period" refers to Scaliger's father,
3719:Noerdlinger, P. (April 1995 revised May 1996).
3441:An introduction to the study of variable stars.
3412:Dionysius Exiguus, 2003 , tr. Michael Deckers,
3343:Philosophical Transactions of the Royal Society
3271:Philosophical Transactions of the Royal Society
1057:
1017:("Work on the Emendation of Time") he states, "
867:
854:Philosophical Transactions of the Royal Society
4018:Theveny, Pierre-Michel. (September 10, 2001).
3961:Kalendariographische und Chronologische Tafeln
3670:, Oxford University Press, pp. 278, 281,
1950:If r<4714, Y = (4714 − r) and is a year BC.
1947:If r>4713, Y = (r − 4713) and is a year AD.
1226:Kalendariographische und Chronologische Tafeln
573:Count of milliseconds, excluding leap seconds
4143:
3564:, vol. 1, 1825, pp. 102–106 (in German).
1512:can be determined from the Julian Day Number
595:Count of nanoseconds, excluding leap seconds
27:Days since the beginning of the Julian Period
8:
1622:Algorithm parameters for Gregorian calendar
1266:Divisions are integer divisions towards zero
1205:era occurred at midnight at the meridian of
1201:wherein he stated that the beginning of the
1137:
3765:, p. 185, Cambridge University Press,
3695:Nautical Almanac and Astronomical Ephemeris
3217:Appendix 2 (Beda Venerabilis' Paschal table
3156:. (2000). U.S. Nautical Almanac Office and
2942:Nautical Almanac and Astronomical Ephemeris
2861:
1413:Finding day of week given Julian day number
1018:
1011:
910:in 1801, restating de Billy's formula as:
4150:
4136:
4128:
4095:: CS1 maint: location missing publisher (
4085:, Washington, pp. introduction 8, 3–5
4060:(ver. 2.2.2). Richmond VA: Willmann-Bell,
4034:Frequently Asked Questions about Calendars
3906:Mapping Time: The Calendar and its History
3822:: CS1 maint: location missing publisher (
2315:
2313:
3797:
3527:
2342:"ECMAScript® 2025 Language Specification"
1956:i = 8, m = 2, s = 8. What is the year?
1375:
1362:
1342:
1339:
1307:
1305:
1279:The algorithm is valid for all (possibly
1260:The algorithm is valid for all (possibly
1174:could not be accurately determined using
554:Count of seconds, excluding leap seconds
4681:International Commission on Stratigraphy
3761:Pallé, Pere L., Esteban, Cesar. (2014).
3245:Journal of the American Oriental Society
2585:
2278:Resolution B1 on the use of Julian Dates
1620:
1528:
1448:
1132:The French mathematician and astronomer
279:
128:cycles) and which preceded any dates in
3510:. London: author. [Google Books version
2257:
2255:
2160:
2099:
2097:
2072:
1150:work in 1860 by the English astronomer
1090:American Ephemeris and Nautical Almanac
986:
889:of the Division, without regard to the
4088:
3815:
3576:COBOL for AIX (2.0): Programming Guide
3416:, Argumentum 5 (in Latin and English).
3172:Astronomical almanac for the year 2017
3154:Astronomical almanac for the year 2001
2812:Blackburn and Holford-Strevens, p. 821
2329:Astronomical almanac for the year 2001
2177:Astronomical Almanac for the year 2017
1001:Although many references say that the
718:. Some implementations or options use
3980:Seidelmann, P. Kenneth (ed.) (1992).
3391:9 (1900) 14–51 (in German and Greek).
3372:3rd ed. Cambridge University Press.
3237:Burgess, Ebenezer, translator. 1860.
3176:Her Majesty's Nautical Almanac Office
3174:. (2016). U.S. Naval Observatory and
3158:Her Majesty's Nautical Almanac Office
2370:"System.DateTime.Ticks documentation"
2236:
2234:
2079:Both of these dates are years of the
7:
2932:1870, pp. 419–424; 1899, pp. 718–722
2508:"Chapter 3. Functions — DATE — Base"
1116:began in 1899 with 2,000 years. The
1112:began in 1879 with 2,000 years. The
1009:, at the beginning of Book V of his
932:is the year of the indiction cycle,
3922:Opvs Novvum de Emendatione Temporvm
3334:, 90: 701–28, col. 705D (in Latin).
2779:Neugebauer 2016, pp. 72–77, 109–114
2197:Dershowitz & Reingold 2008, 15.
1798:For Julian or Gregorian, continue:
1080:used over 2,800 Julian days in his
893:, shall be the year enquired after.
112:(November 24, 4714 BC, in the
42:. For the artist and composer, see
4013:SOFA Time Scale and Calendar Tools
3409:vol. 67, cols. 493–508 (in Latin).
3240:Translation of the Surya Siddhanta
1980:Standards of Fundamental Astronomy
676:(1919). This epoch was noon UT on
587:(JD − 2440587.5) × 86400000000000
25:
4401:Discrete time and continuous time
3250:(1858–1860) 141–498, p. 161.
4326:
4320:
3697:, London, 1767–1923, Hathi Trust
3438:Furness, Caroline Ellen (1915).
3414:Nineteen year cycle of Dionysius
3286:table of contents at end of book
3224:The Oxford Companion to the Year
2954:Berliner Astronomisches Jahrbuch
2587:Calculation of 4845, 4200, 6916
2228:McCarthy & Guinot 2013, 91–2
1962:102488/7980 = 12 remainder 6728.
1268:; fractional parts are ignored.
1114:Berliner Astronomisches Jahrbuch
674:Tables of the Motion of the Moon
614:(JD − 1721425.5) × 864000000000
221:International Astronomical Union
34:. For numbered day of year, see
3936:, typis Rouerianis, p. 361
3706:Ethiopic Astronomy and Computus
3403:Cyclus Decemnovennalis Dionysii
3398:Modified Julian Day explanation
3394:Digital Equipment Corporation.
3324:. Retrieved September 28, 2019.
3132:Alsted, Johann Heinrich 1649 .
1039:Julian days were first used by
268:UT unless otherwise specified.
136:(noon) on January 1, 2000, was
4474:History of timekeeping devices
3463:. Article 36. pp. 25–26.
3457:Gauss, Carl Frederich (1801).
1182:days beginning at sunrise and
696:time-of-day. It was named for
255:Because the starting point or
1:
4043:
3943:"Hilfstafeln für Chronologie"
3849:
3666:Mosshammer, Alden A. (2008),
3516:Herschel, John F. W. (1849),
3328:"De argumentis lunæ libellus"
3290:Chronicon Paschale 284–628 AD
3005:
2761:Reese, Everett and Craun 1981
2450:
2404:Digital Equipment Corporation
2262:
1233:Julian day number calculation
734:. In Rexx January 1 is Day 0.
664:used from 1900 through 1983,
3933:Opvs de Emendatione Temporvm
3536:Hopkins, Jeffrey L. (2013).
3435:Vol. 11 No. 10, p. 657.
3258:Chi, A. R. (December 1979).
3083:Richards 2013, pp. 592, 618.
2744:
2719:
2701:
2696:
2671:
2653:
2648:
2623:
2605:
2595:
2440:SPD Toolkit Time Notes 2014.
1965:Y = (6728 − 4713) = AD 2015.
1013:Opus de Emendatione Temporum
732:proleptic Gregorian calendar
609:proleptic Gregorian calendar
565:(JD − 2440587.5) × 86400000
496:proleptic Gregorian calendar
114:proleptic Gregorian calendar
4421:Gravitational time dilation
4257:Barycentric Coordinate Time
3908:. Oxford University Press.
3871:American Journal of Physics
3727:Goddard Space Flight Center
3624:Traité de Mécanique Céleste
3583:Information Bulletin No. 81
3486:Grafton, Anthony T. (1994)
3460:Disquisitiones Arithmeticae
3449:Disquisitiones Arithmeticae
3345:, series 1665–1678, volume
3273:, series 1665–1678, volume
3265:Collins, John (1666–1667).
3226:, Oxford University Press,
3205:Bede: The Reckoning of Time
3191:Astronomical Almanac Online
2893:Herschel, 1849, p. 632 note
2801:De argumentis lunæ libellus
2522:Richards 2013, pp. 591–592.
2512:z/VM: 7.1 REXX/VM Reference
2487:The Python Standard Library
2135:24, numbered from Sunday=1.
1791:) div 146097) × 3) div 4 +
1246:astronomical year numbering
1222:Hilfstafeln für Chronologie
1160:Harvard College Observatory
1139:Traité de Mécanique Céleste
877:, by 4200, and that of the
666:Newcomb's Tables of the Sun
616:
589:
567:
548:
527:
503:
474:
450:
426:
401:
378:
355:
337:
319:
237:Barycentric Coordinate Time
4943:
4277:Geocentric Coordinate Time
4262:Barycentric Dynamical Time
4200:Coordinated Universal Time
4028:Tøndering, Claus. (2014).
3806:Peirce, Benjamin (1865) ,
3502:, 1958, 31–55 (in French).
3401:Dionysius Exiguus, 1863 ,
3197:December 24, 2016, at the
3056:Richards 1998, pp. 287–342
2821:Mosshammer 2008, pp. 80–85
2791:Dionysius Exiguus 2003/525
1068:At least one mathematical
913:Julian Period year = (6916
241:Coordinated Universal Time
48:
29:
4431:Time-translation symmetry
4318:
4242:International Atomic Time
4169:
4079:Winlock, Joseph (1864) ,
3964:, Leipzig: J. C. Hinrichs
3930:Scaliger, Joseph (1629),
3919:Scaliger, Joseph (1583),
3389:Byzantinische Zeitschrift
3309:December 3, 2020, at the
2745:532×13 = 28×19×13 = 6916
2697:420×10 = 28×15×10 = 4200
2649:285×17 = 19×15×17 = 4845
2249:US Naval Observatory 2005
1121:day number" in 1918. The
546:(JD − 2440587.5) × 86400
469:day 1 = October 15, 1582
312:proleptic Julian calendar
229:International Atomic Time
110:proleptic Julian calendar
4071:Winkler, M. R. (n. d.).
3969:"SDP Toolkit Time Notes"
3904:Richards, E. G. (1998).
3885:XXIIIrd General Assembly
3732:Nothaft, C. Philipp E.,
3614:Kempler, Steve. (2011).
3607:October 6, 2007, at the
3555:. (April 4, 2013). NASA.
3522:(2nd ed.), London,
3369:Calendrical Calculations
2875:Ideler 1825, pp. 102–106
2406:-Customer Support Center
2089:astronomical year number
1768:For Gregorian calendar:
1508:The ISO day of the week
1156:Edward Charles Pickering
936:of the lunar cycle, and
522:12:00 December 29, 1873
396:12:00 December 31, 1899
332:12:00 November 16, 1858
308:12:00 January 1, 4713 BC
49:Not to be confused with
4691:Astronomical chronology
4664:Archaeology and geology
4371:Absolute space and time
4287:IERS Reference Meridian
4282:International Date Line
4193:International standards
4113:"Julian Date Converter"
3958:Schram, Robert (1908),
3941:Schram, Robert (1882),
3757:doi:10.1147/sj.252.0244
3653:Astronomical Algorithms
3628:p. 348 (in French)
3529:2027/njp.32101032311266
2289:Seidelmann 2013, p. 15.
1998:Barycentric Julian Date
1969:Julian date calculation
1801:
873:Cycle by 4845, and the
741:Heliocentric Julian Day
525:(JD − 2405522)/1.02749
501:floor (JD − 1721424.5)
472:floor (JD − 2299159.5)
376:floor (JD − 2440000.5)
350:0:00 November 17, 1858
51:Julian year (astronomy)
4115:. US Naval Observatory
4073:"Modified Julian Date"
3971:. (July 21, 2014). In
3799:10.1093/mnras/20.7.283
3337:de Billy (1665–1666).
3284:1689–1922, Hathi Trust
3282:Connaissance des Temps
2930:Connaissance des Temps
2862:
2510:(September 29, 2022).
2034:Julian year (calendar)
2018:Epoch (reference date)
1393:
1138:
1127:Connaissance des Temps
1106:Connaissance des Temps
1066:
1019:
1012:
901:
533:Count of Martian days
219:), but since 1997 the
4912:Calendaring standards
4650:Weekday determination
4536:Sundial markup schema
3974:SDP Toolkit / HDF-EOS
3601:Julian Date Converter
3519:Outlines of Astronomy
3476:/2 pp. 156–185.
3356:, 24 (1987), 137–139.
2851:Scaliger 1629, p. 361
2833:Herschel 1849, p. 634
2298:Hopkins 2013, p. 257.
2240:"Resolution B1" 1997.
1750:For Julian calendar:
1516:with the expression:
1432:with the expression:
1394:
1053:Outlines of Astronomy
863:Outlines of Astronomy
584:0:00 January 1, 1970
562:0:00 January 1, 1970
543:0:00 January 1, 1970
509:Count of days of the
493:day 1 = January 1, 1
480:Count of days of the
445:0:00 January 1, 1958
421:0:00 January 1, 1950
274:) and may be cached.
4671:Chronological dating
4411:Theory of relativity
4272:Daylight saving time
4051:Julian date calendar
3747:Ohms, B. G. (1986).
3616:Day of Year Calendar
3322:IBM Knowledge Center
3092:Richards 2013, 617–9
2531:Grafton 1975, p. 184
2485:(December 5, 2021).
2307:Pallé, Esteban 2014.
1304:
1134:Pierre-Simon Laplace
940:of the solar cycle.
904:Carl Friedrich Gauss
706:is a system used in
631:Modified Julian Date
263:In the table below,
4917:Celestial mechanics
4907:Calendar algorithms
4881:Time value of money
4676:Geologic time scale
4531:History of sundials
4396:Cosmological decade
4348:Greenwich Mean Time
4179:Orders of magnitude
4030:"The Julian Period"
4023:The TPtime Handbook
3848:Ransom, D. H. Jr. (
3790:1860MNRAS..20..283P
3753:IBM Systems Journal
3277:, pp. 568–575.
3110:Heath 1760, p. 160.
2590:
2206:Seidelman 2013, 15.
2060:Zeller's congruence
1623:
1049:John F. W. Herschel
859:John F. W. Herschel
591:1.7271220810032E+18
213:Greenwich Mean Time
44:Julian Day (artist)
4856:Mental chronometry
4484:Marine chronometer
4336:Obsolete standards
3833:Ptolemy's Almagest
3809:Tables of the Moon
3505:Heath, B. (1760).
3471:History and Theory
3101:Richards 1998, 316
2966:American Ephemeris
2902:Ideler 1825, p. 77
2842:Diekamp 44, 45, 50
2586:
2167:"Julian date" n.d.
1621:
1421:The US day of the
1389:
1387:
1211:February 17 and 18
1118:American Ephemeris
1082:Tables of the Moon
1078:Harvard University
1035:Julian day numbers
987:Julian day numbers
857:(its first year).
830:remainder division
815:was Julian Period
618:638627188810032000
606:0:00 January 1, 1
482:Gregorian calendar
456:Introduced by the
432:Introduced by the
407:Introduced by the
373:0:00 May 24, 1968
260:24-hour notation.
206:"Julian calendars"
194:Gregorian calendar
4927:Time in astronomy
4894:
4893:
4704:Nuclear timescale
4386:Continuous signal
4082:Tables of Mercury
4007:978-1-891389-85-6
3900:978-1-89138-985-6
3831:Ptolemy (1998) ,
3742:978-0-19-879955-9
3714:978-1-56902-440-9
3685:Sky and Telescope
3677:978-0-19-954312-0
3644:978-1-89138-985-6
3407:Patrologia Latina
3378:978-0-521-70238-6
3332:Patrologia Latina
3298:978-0-85323-096-0
2968:1925, pp. 746–749
2956:1899, pp. 390–391
2749:
2748:
2041:(similar concept)
2013:Epoch (astronomy)
1993:5th millennium BC
1748:
1747:
1583:
1582:
1503:
1502:
1383:
1379:
1370:
1366:
1357:
1345:
1099:Tables of Mercury
960:Dionysius Exiguus
771:Julian day number
693:Lilian day number
626:
625:
276:
98:Julian day number
16:(Redirected from
4934:
4595:Dominical letter
4526:Equation of time
4489:Marine sandglass
4330:
4324:
4302:Terrestrial Time
4159:Time measurement
4152:
4145:
4138:
4129:
4124:
4122:
4120:
4100:
4094:
4086:
4048:
4045:
3965:
3954:
3937:
3926:
3877:, pages 658–661.
3854:
3851:
3845:
3827:
3821:
3813:
3802:
3801:
3763:Asteroseismology
3680:
3655:(1998), 2nd ed,
3621:Laplace (1823).
3558:Ideler, Ludwig.
3532:
3531:
3466:
3454:
3184:978-0-7077-41666
3140:
3120:
3117:
3111:
3108:
3102:
3099:
3093:
3090:
3084:
3081:
3075:
3072:
3066:
3063:
3057:
3054:
3048:
3045:
3039:
3036:
3030:
3027:
3021:
3018:
3012:
3010:
3007:
3002:
2996:
2993:
2987:
2984:
2978:
2975:
2969:
2963:
2957:
2951:
2945:
2939:
2933:
2927:
2921:
2918:
2912:
2909:
2903:
2900:
2894:
2891:
2885:
2882:
2876:
2873:
2867:
2865:
2858:
2852:
2849:
2843:
2840:
2834:
2831:
2822:
2819:
2813:
2810:
2804:
2798:
2792:
2789:
2780:
2777:
2771:
2768:
2762:
2759:
2750:
2742:
2737:
2735:
2734:
2731:
2728:
2716:
2714:
2713:
2710:
2707:
2694:
2689:
2687:
2686:
2683:
2680:
2668:
2666:
2665:
2662:
2659:
2646:
2641:
2639:
2638:
2635:
2632:
2620:
2618:
2617:
2614:
2611:
2591:
2583:
2577:
2574:
2568:
2565:
2559:
2556:
2550:
2547:
2541:
2538:
2532:
2529:
2523:
2520:
2514:
2505:
2499:
2496:
2490:
2480:
2474:
2471:
2465:
2462:
2456:
2455:
2452:
2447:
2441:
2438:
2432:
2429:
2423:
2420:
2414:
2413:
2412:on June 6, 2007.
2395:
2389:
2388:
2383:
2381:
2366:
2360:
2359:
2352:
2346:
2345:
2338:
2332:
2326:
2320:
2317:
2308:
2305:
2299:
2296:
2290:
2287:
2281:
2275:
2269:
2267:
2264:
2259:
2250:
2247:
2241:
2238:
2229:
2226:
2220:
2217:Terrestrial Time
2213:
2207:
2204:
2198:
2195:
2189:
2186:
2180:
2174:
2168:
2165:
2149:
2142:
2136:
2134:
2129:
2123:
2120:
2114:
2110:
2104:
2101:
2092:
2077:
1624:
1616:modulus operator
1604:integer division
1558:Day of the week
1529:
1478:Day of the week
1449:
1398:
1396:
1395:
1390:
1388:
1384:
1377:
1376:
1371:
1364:
1363:
1358:
1353:
1346:
1343:
1340:
1239:integer division
1219:
1215:
1212:
1190:
1167:astronomical day
1141:
1123:Nautical Almanac
1110:Nautical Almanac
1095:
1063:
1022:
1015:
996:
981:
977:
973:
969:
908:modulo operation
899:
898:Jacques de Billy
849:Jacques de Billy
843:
839:
835:
822:
818:
814:
806:
802:
773:is based on the
611:
581:File Timestamps
559:JavaScript Date
498:
314:
309:
296:
280:
275:
233:Terrestrial Time
225:Terrestrial Time
171:
170:
166:
163:
145:
144:
141:
130:recorded history
92:
84:
21:
4942:
4941:
4937:
4936:
4935:
4933:
4932:
4931:
4897:
4896:
4895:
4890:
4827:
4718:
4685:
4659:
4540:
4440:
4391:Coordinate time
4363:Time in physics
4357:
4331:
4325:
4316:
4188:
4165:
4156:
4118:
4116:
4111:
4108:
4103:
4087:
4078:
4046:
3957:
3940:
3929:
3918:
3881:"Resolution B1"
3852:
3843:
3830:
3814:
3805:
3775:
3702:Otto Neugebauer
3678:
3665:
3609:Wayback Machine
3552:HORIZONS System
3515:
3464:
3452:
3383:Franz Diekamp,
3364:Reingold, E. M.
3311:Wayback Machine
3199:Wayback Machine
3138:
3128:
3123:
3118:
3114:
3109:
3105:
3100:
3096:
3091:
3087:
3082:
3078:
3073:
3069:
3064:
3060:
3055:
3051:
3046:
3042:
3037:
3033:
3028:
3024:
3019:
3015:
3008:
3003:
2999:
2994:
2990:
2985:
2981:
2976:
2972:
2964:
2960:
2952:
2948:
2940:
2936:
2928:
2924:
2919:
2915:
2910:
2906:
2901:
2897:
2892:
2888:
2883:
2879:
2874:
2870:
2859:
2855:
2850:
2846:
2841:
2837:
2832:
2825:
2820:
2816:
2811:
2807:
2799:
2795:
2790:
2783:
2778:
2774:
2769:
2765:
2760:
2753:
2740:
2739:
2732:
2729:
2723:
2722:
2720:
2711:
2708:
2705:
2704:
2702:
2692:
2691:
2684:
2681:
2675:
2674:
2672:
2669:= 28×15 = 420
2663:
2660:
2657:
2656:
2654:
2644:
2643:
2636:
2633:
2627:
2626:
2624:
2615:
2612:
2609:
2608:
2606:
2588:
2584:
2580:
2575:
2571:
2566:
2562:
2557:
2553:
2548:
2544:
2539:
2535:
2530:
2526:
2521:
2517:
2506:
2502:
2497:
2493:
2481:
2477:
2472:
2468:
2463:
2459:
2453:
2448:
2444:
2439:
2435:
2430:
2426:
2421:
2417:
2397:
2396:
2392:
2379:
2377:
2368:
2367:
2363:
2354:
2353:
2349:
2340:
2339:
2335:
2327:
2323:
2318:
2311:
2306:
2302:
2297:
2293:
2288:
2284:
2276:
2272:
2265:
2260:
2253:
2248:
2244:
2239:
2232:
2227:
2223:
2214:
2210:
2205:
2201:
2196:
2192:
2187:
2183:
2175:
2171:
2166:
2162:
2158:
2153:
2152:
2143:
2139:
2132:
2130:
2126:
2121:
2117:
2111:
2107:
2102:
2095:
2078:
2074:
2069:
2064:
2039:Lunation Number
1988:
1971:
1966:
1963:
1960:
1951:
1948:
1942:
1923:
1614:)" denotes the
1598: div
1588:
1527:
1447:
1415:
1399:
1386:
1385:
1341:
1323:
1318:
1302:
1301:
1292:
1287:
1277:
1272:
1258:
1235:
1217:
1213:
1210:
1198:Surya Siddhanta
1189:January 1, 1925
1188:
1093:
1074:Benjamin Peirce
1061:
1037:
1029:Julian calendar
1007:Julius Scaliger
994:
979:
975:
971:
967:
926:
906:introduced the
900:
897:
851:in 1665 in the
841:
837:
833:
820:
819:. He knew that
816:
812:
804:
800:
797:
794:indiction cycle
779:Joseph Scaliger
767:
762:
698:Aloysius Lilius
670:Ernest W. Brown
607:
494:
448:JD − 2436204.5
424:JD − 2433282.5
353:JD − 2400000.5
310:
307:
257:reference epoch
253:
198:Julian calendar
182:
168:
164:
161:
159:
142:
139:
137:
90:
87:Julian calendar
83:4713 BC (−4712)
82:
54:
47:
32:Julian calendar
28:
23:
22:
15:
12:
11:
5:
4940:
4938:
4930:
4929:
4924:
4919:
4914:
4909:
4899:
4898:
4892:
4891:
4889:
4888:
4883:
4878:
4876:Time metrology
4873:
4868:
4863:
4858:
4853:
4852:
4851:
4841:
4835:
4833:
4832:Related topics
4829:
4828:
4826:
4825:
4820:
4815:
4810:
4805:
4800:
4795:
4790:
4785:
4780:
4775:
4770:
4765:
4760:
4755:
4750:
4745:
4740:
4735:
4729:
4727:
4720:
4719:
4717:
4716:
4711:
4706:
4701:
4695:
4693:
4687:
4686:
4684:
4683:
4678:
4673:
4667:
4665:
4661:
4660:
4658:
4657:
4652:
4647:
4642:
4637:
4632:
4627:
4622:
4617:
4612:
4607:
4602:
4597:
4592:
4587:
4582:
4577:
4571:
4566:
4561:
4556:
4550:
4548:
4542:
4541:
4539:
4538:
4533:
4528:
4523:
4521:Dialing scales
4518:
4513:
4508:
4507:
4506:
4496:
4491:
4486:
4481:
4476:
4471:
4466:
4461:
4456:
4450:
4448:
4442:
4441:
4439:
4438:
4433:
4428:
4423:
4418:
4413:
4408:
4403:
4398:
4393:
4388:
4383:
4378:
4373:
4367:
4365:
4359:
4358:
4356:
4355:
4353:Prime meridian
4350:
4345:
4343:Ephemeris time
4339:
4337:
4333:
4332:
4319:
4317:
4315:
4314:
4312:180th meridian
4309:
4304:
4299:
4294:
4289:
4284:
4279:
4274:
4269:
4264:
4259:
4254:
4249:
4244:
4239:
4234:
4229:
4224:
4219:
4214:
4209:
4208:
4207:
4196:
4194:
4190:
4189:
4187:
4186:
4181:
4176:
4170:
4167:
4166:
4157:
4155:
4154:
4147:
4140:
4132:
4126:
4125:
4107:
4106:External links
4104:
4102:
4101:
4076:
4069:
4054:
4037:
4026:
4016:
4009:
3995:
3978:
3966:
3955:
3938:
3927:
3916:
3914:978-0192862051
3902:
3888:
3878:
3863:
3846:
3841:
3828:
3803:
3784:(7): 283–285,
3773:
3759:
3745:
3730:
3717:
3699:
3691:
3681:
3676:
3663:
3646:
3629:
3619:
3612:
3597:
3587:
3579:
3565:
3556:
3548:
3534:
3513:
3503:
3499:La chronologie
3494:Venance Grumel
3491:
3484:
3467:
3455:
3445:
3436:
3425:
3417:
3410:
3399:
3392:
3381:
3360:Dershowitz, N.
3357:
3350:
3335:
3325:
3314:
3301:
3287:
3278:
3263:
3256:
3251:
3235:
3220:
3202:
3187:
3169:
3151:
3146:
3129:
3127:
3124:
3122:
3121:
3112:
3103:
3094:
3085:
3076:
3067:
3058:
3049:
3040:
3031:
3022:
3013:
2997:
2988:
2979:
2970:
2958:
2946:
2934:
2922:
2913:
2904:
2895:
2886:
2877:
2868:
2853:
2844:
2835:
2823:
2814:
2805:
2793:
2781:
2772:
2763:
2751:
2747:
2746:
2743:
2718:
2717:= 28×19 = 532
2699:
2698:
2695:
2670:
2651:
2650:
2647:
2622:
2621:= 19×15 = 285
2603:
2602:
2600:
2594:
2578:
2569:
2560:
2551:
2542:
2533:
2524:
2515:
2500:
2491:
2475:
2466:
2457:
2442:
2433:
2424:
2415:
2390:
2361:
2347:
2333:
2321:
2309:
2300:
2291:
2282:
2270:
2251:
2242:
2230:
2221:
2208:
2199:
2190:
2181:
2169:
2159:
2157:
2154:
2151:
2150:
2137:
2124:
2115:
2105:
2093:
2071:
2070:
2068:
2065:
2063:
2062:
2057:
2055:Time standards
2052:
2047:
2042:
2036:
2031:
2025:
2020:
2015:
2010:
2005:
2000:
1995:
1989:
1987:
1984:
1970:
1967:
1964:
1961:
1958:
1949:
1946:
1941:
1938:
1922:
1921:
1888:
1866:
1852:
1835:
1818:
1800:
1796:
1795:
1766:
1765:
1746:
1745:
1742:
1737:
1734:
1728:
1727:
1724:
1719:
1716:
1710:
1709:
1706:
1701:
1698:
1692:
1691:
1688:
1683:
1680:
1674:
1673:
1670:
1665:
1662:
1656:
1655:
1652:
1647:
1644:
1638:
1637:
1634:
1631:
1628:
1587:
1584:
1581:
1580:
1577:
1574:
1571:
1568:
1565:
1562:
1559:
1555:
1554:
1551:
1548:
1545:
1542:
1539:
1536:
1533:
1518:
1501:
1500:
1497:
1494:
1491:
1488:
1485:
1482:
1479:
1475:
1474:
1471:
1468:
1465:
1462:
1459:
1456:
1453:
1434:
1414:
1411:
1409:= 2451544.75.
1382:
1374:
1369:
1361:
1356:
1352:
1349:
1338:
1335:
1331:
1327:
1324:
1322:
1319:
1317:
1313:
1310:
1309:
1300:
1291:
1288:
1285:
1276:
1273:
1270:
1257:
1254:
1234:
1231:
1036:
1033:
1027:refers to the
956:Era of Martyrs
925:) MOD 15×19×28
912:
895:
813:1 BC or year 0
796:) = 7980 years
783:
766:
765:Julian Period
763:
761:
758:
757:
756:
736:
735:
720:Universal Time
701:
689:
658:
646:
624:
623:
620:
615:
612:
604:
597:
596:
593:
588:
585:
582:
575:
574:
571:
566:
563:
560:
556:
555:
552:
547:
544:
541:
535:
534:
531:
526:
523:
520:
514:
513:
507:
502:
499:
491:
485:
484:
478:
473:
470:
467:
461:
460:
454:
449:
446:
443:
437:
436:
430:
425:
422:
419:
413:
412:
405:
400:
397:
394:
390:
389:
384:Introduced by
382:
377:
374:
371:
367:
366:
361:Introduced by
359:
354:
351:
348:
344:
343:
341:
336:
333:
330:
326:
325:
323:
318:
315:
305:
301:
300:
297:
292:
289:
284:
252:
249:
217:Ephemeris Time
215:(GMT) (later,
181:
178:
102:Universal Time
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
4939:
4928:
4925:
4923:
4920:
4918:
4915:
4913:
4910:
4908:
4905:
4904:
4902:
4887:
4884:
4882:
4879:
4877:
4874:
4872:
4869:
4867:
4864:
4862:
4859:
4857:
4854:
4850:
4847:
4846:
4845:
4842:
4840:
4837:
4836:
4834:
4830:
4824:
4821:
4819:
4816:
4814:
4811:
4809:
4806:
4804:
4801:
4799:
4796:
4794:
4791:
4789:
4786:
4784:
4781:
4779:
4776:
4774:
4771:
4769:
4766:
4764:
4761:
4759:
4756:
4754:
4751:
4749:
4746:
4744:
4741:
4739:
4736:
4734:
4731:
4730:
4728:
4726:
4725:units of time
4721:
4715:
4714:Sidereal time
4712:
4710:
4707:
4705:
4702:
4700:
4699:Galactic year
4697:
4696:
4694:
4692:
4688:
4682:
4679:
4677:
4674:
4672:
4669:
4668:
4666:
4662:
4656:
4655:Weekday names
4653:
4651:
4648:
4646:
4645:Tropical year
4643:
4641:
4638:
4636:
4633:
4631:
4628:
4626:
4623:
4621:
4618:
4616:
4613:
4611:
4610:Intercalation
4608:
4606:
4603:
4601:
4598:
4596:
4593:
4591:
4588:
4586:
4583:
4581:
4578:
4576:(lunar Hijri)
4575:
4572:
4570:
4567:
4565:
4562:
4560:
4557:
4555:
4552:
4551:
4549:
4547:
4543:
4537:
4534:
4532:
4529:
4527:
4524:
4522:
4519:
4517:
4514:
4512:
4509:
4505:
4502:
4501:
4500:
4497:
4495:
4492:
4490:
4487:
4485:
4482:
4480:
4477:
4475:
4472:
4470:
4467:
4465:
4462:
4460:
4457:
4455:
4452:
4451:
4449:
4447:
4443:
4437:
4434:
4432:
4429:
4427:
4424:
4422:
4419:
4417:
4416:Time dilation
4414:
4412:
4409:
4407:
4404:
4402:
4399:
4397:
4394:
4392:
4389:
4387:
4384:
4382:
4379:
4377:
4374:
4372:
4369:
4368:
4366:
4364:
4360:
4354:
4351:
4349:
4346:
4344:
4341:
4340:
4338:
4334:
4329:
4323:
4313:
4310:
4308:
4305:
4303:
4300:
4298:
4295:
4293:
4290:
4288:
4285:
4283:
4280:
4278:
4275:
4273:
4270:
4268:
4265:
4263:
4260:
4258:
4255:
4253:
4252:24-hour clock
4250:
4248:
4247:12-hour clock
4245:
4243:
4240:
4238:
4235:
4233:
4230:
4228:
4225:
4223:
4220:
4218:
4215:
4213:
4210:
4206:
4203:
4202:
4201:
4198:
4197:
4195:
4191:
4185:
4182:
4180:
4177:
4175:
4172:
4171:
4168:
4164:
4160:
4153:
4148:
4146:
4141:
4139:
4134:
4133:
4130:
4114:
4110:
4109:
4105:
4098:
4092:
4084:
4083:
4077:
4074:
4070:
4067:
4066:0-943396-84-0
4063:
4059:
4055:
4052:
4041:
4038:
4035:
4031:
4027:
4024:
4021:
4020:"Date Format"
4017:
4014:
4010:
4008:
4004:
4000:
3996:
3993:
3992:0-935702-68-7
3989:
3985:
3984:
3979:
3976:
3975:
3970:
3967:
3963:
3962:
3956:
3952:
3948:
3944:
3939:
3935:
3934:
3928:
3925:, p. 198
3924:
3923:
3917:
3915:
3911:
3907:
3903:
3901:
3897:
3893:
3889:
3886:
3882:
3879:
3876:
3872:
3868:
3864:
3861:
3859:
3847:
3844:
3842:0-691-00260-6
3838:
3834:
3829:
3825:
3819:
3811:
3810:
3804:
3800:
3795:
3791:
3787:
3783:
3779:
3774:
3772:
3771:9781107470620
3768:
3764:
3760:
3758:
3755:25, 244–251.
3754:
3750:
3746:
3743:
3739:
3735:
3731:
3728:
3724:
3723:
3718:
3715:
3711:
3707:
3703:
3700:
3698:
3696:
3692:
3689:
3686:
3682:
3679:
3673:
3669:
3664:
3662:
3661:0-943396-61-1
3658:
3654:
3650:
3647:
3645:
3641:
3637:
3633:
3630:
3627:
3625:
3620:
3617:
3613:
3610:
3606:
3603:
3602:
3598:
3595:
3591:
3590:"Julian Date"
3588:
3585:
3584:
3580:
3577:
3573:
3569:
3566:
3563:
3562:
3557:
3554:
3553:
3549:
3547:
3546:9783319014425
3543:
3539:
3535:
3530:
3525:
3521:
3520:
3514:
3511:
3509:
3504:
3501:
3500:
3495:
3492:
3489:
3485:
3483:
3479:
3475:
3472:
3468:
3462:
3461:
3456:
3450:
3446:
3443:
3442:
3437:
3434:
3430:
3426:
3423:
3422:
3418:
3415:
3411:
3408:
3404:
3400:
3397:
3393:
3390:
3386:
3382:
3379:
3375:
3371:
3370:
3365:
3361:
3358:
3355:
3351:
3348:
3344:
3340:
3336:
3333:
3329:
3326:
3323:
3319:
3315:
3312:
3308:
3305:
3302:
3299:
3295:
3291:
3288:
3285:
3283:
3279:
3276:
3272:
3268:
3264:
3261:
3257:
3255:
3252:
3249:
3246:
3242:
3241:
3236:
3233:
3232:0-19-214231-3
3229:
3225:
3221:
3218:
3214:
3213:0-85323-693-3
3210:
3206:
3203:
3200:
3196:
3193:
3192:
3188:
3185:
3181:
3177:
3173:
3170:
3167:
3166:9780117728431
3163:
3159:
3155:
3152:
3150:
3147:
3144:
3137:
3136:
3135:Encyclopaedia
3131:
3130:
3125:
3116:
3113:
3107:
3104:
3098:
3095:
3089:
3086:
3080:
3077:
3071:
3068:
3062:
3059:
3053:
3050:
3044:
3041:
3035:
3032:
3026:
3023:
3017:
3014:
3001:
2998:
2995:Furness 1915.
2992:
2989:
2983:
2980:
2974:
2971:
2967:
2962:
2959:
2955:
2950:
2947:
2943:
2938:
2935:
2931:
2926:
2923:
2917:
2914:
2908:
2905:
2899:
2896:
2890:
2887:
2881:
2878:
2872:
2869:
2864:
2857:
2854:
2848:
2845:
2839:
2836:
2830:
2828:
2824:
2818:
2815:
2809:
2806:
2802:
2797:
2794:
2788:
2786:
2782:
2776:
2773:
2767:
2764:
2758:
2756:
2752:
2727:
2700:
2679:
2652:
2631:
2604:
2601:
2598:
2593:
2592:
2582:
2579:
2573:
2570:
2564:
2561:
2555:
2552:
2549:Herschel 1849
2546:
2543:
2540:de Billy 1665
2537:
2534:
2528:
2525:
2519:
2516:
2513:
2509:
2504:
2501:
2495:
2492:
2488:
2484:
2479:
2476:
2470:
2467:
2461:
2458:
2446:
2443:
2437:
2434:
2428:
2425:
2422:Winkler n. d.
2419:
2416:
2411:
2407:
2405:
2400:
2394:
2391:
2387:
2375:
2371:
2365:
2362:
2357:
2351:
2348:
2343:
2337:
2334:
2331:, 2000, p. K2
2330:
2325:
2322:
2319:Theveny 2001.
2316:
2314:
2310:
2304:
2301:
2295:
2292:
2286:
2283:
2279:
2274:
2271:
2258:
2256:
2252:
2246:
2243:
2237:
2235:
2231:
2225:
2222:
2218:
2212:
2209:
2203:
2200:
2194:
2191:
2185:
2182:
2178:
2173:
2170:
2164:
2161:
2155:
2147:
2141:
2138:
2128:
2125:
2119:
2116:
2109:
2106:
2100:
2098:
2094:
2090:
2086:
2082:
2076:
2073:
2066:
2061:
2058:
2056:
2053:
2051:
2048:
2046:
2043:
2040:
2037:
2035:
2032:
2029:
2026:
2024:
2021:
2019:
2016:
2014:
2011:
2009:
2006:
2004:
2001:
1999:
1996:
1994:
1991:
1990:
1985:
1983:
1981:
1977:
1968:
1957:
1954:
1945:
1939:
1937:
1935:
1931:
1927:
1920:
1916:
1912:
1908:
1904:
1900:
1896:
1892:
1889:
1886:
1882:
1878:
1874:
1870:
1867:
1864:
1860:
1856:
1853:
1851:
1847:
1843:
1839:
1836:
1834:
1830:
1826:
1822:
1819:
1817:
1813:
1809:
1805:
1802:
1799:
1794:
1790:
1786:
1782:
1778:
1774:
1771:
1770:
1769:
1764:
1760:
1756:
1753:
1752:
1751:
1743:
1741:
1738:
1735:
1733:
1730:
1729:
1725:
1723:
1720:
1717:
1715:
1712:
1711:
1707:
1705:
1702:
1699:
1697:
1694:
1693:
1689:
1687:
1684:
1681:
1679:
1676:
1675:
1671:
1669:
1666:
1663:
1661:
1658:
1657:
1653:
1651:
1648:
1645:
1643:
1640:
1639:
1635:
1632:
1629:
1626:
1625:
1619:
1617:
1613:
1609:
1605:
1601:
1597:
1593:
1585:
1578:
1575:
1572:
1569:
1566:
1563:
1560:
1557:
1556:
1552:
1549:
1546:
1543:
1540:
1537:
1534:
1531:
1530:
1525:
1521:
1517:
1515:
1511:
1506:
1498:
1495:
1492:
1489:
1486:
1483:
1480:
1477:
1476:
1472:
1469:
1466:
1463:
1460:
1457:
1454:
1451:
1450:
1445:
1441:
1437:
1433:
1431:
1427:
1424:
1419:
1412:
1410:
1408:
1404:
1380:
1372:
1367:
1359:
1354:
1350:
1347:
1336:
1333:
1329:
1325:
1320:
1315:
1311:
1299:
1297:
1289:
1284:
1282:
1274:
1269:
1267:
1263:
1255:
1253:
1251:
1247:
1242:
1240:
1232:
1230:
1227:
1223:
1208:
1204:
1200:
1199:
1192:
1185:
1181:
1177:
1172:
1168:
1163:
1161:
1157:
1153:
1152:Norman Pogson
1149:
1148:variable star
1145:
1140:
1135:
1130:
1128:
1124:
1119:
1115:
1111:
1107:
1102:
1100:
1091:
1087:
1083:
1079:
1075:
1071:
1065:
1056:
1054:
1050:
1046:
1042:
1041:Ludwig Ideler
1034:
1032:
1030:
1026:
1021:
1016:
1014:
1008:
1004:
999:
992:
991:Byzantine Era
988:
983:
965:
961:
957:
951:
949:
945:
941:
939:
935:
931:
924:
920:
916:
911:
909:
905:
894:
892:
888:
884:
883:Julian Period
880:
876:
872:
869:Multiply the
866:
864:
860:
856:
855:
850:
845:
831:
826:
825:Paschal cycle
808:
795:
791:
787:
782:
780:
776:
775:Julian Period
772:
764:
759:
754:
750:
746:
742:
738:
737:
733:
729:
725:
721:
717:
713:
709:
705:
702:
699:
694:
690:
687:
683:
679:
675:
671:
667:
663:
659:
655:
651:
647:
644:
640:
636:
632:
628:
627:
621:
619:
613:
610:
605:
602:
599:
598:
594:
592:
586:
583:
580:
577:
576:
572:
570:
569:1727122081003
564:
561:
558:
557:
553:
551:
545:
542:
540:
537:
536:
532:
530:
524:
521:
519:
518:Mars Sol Date
516:
515:
512:
508:
506:
500:
497:
492:
490:
487:
486:
483:
479:
477:
471:
468:
466:
463:
462:
459:
455:
453:
447:
444:
442:
439:
438:
435:
431:
429:
423:
420:
418:
415:
414:
410:
406:
404:
399:JD − 2415020
398:
395:
392:
391:
387:
383:
381:
375:
372:
370:Truncated JD
369:
368:
364:
360:
358:
352:
349:
346:
345:
342:
340:
335:JD − 2400000
334:
331:
328:
327:
324:
322:
321:2460577.33889
316:
313:
306:
303:
302:
298:
295:Current value
293:
290:
288:
285:
282:
281:
278:
277:
273:
266:
261:
258:
250:
248:
246:
242:
238:
234:
230:
226:
222:
218:
214:
209:
207:
203:
199:
195:
191:
187:
179:
177:
175:
156:
152:
147:
135:
131:
127:
123:
119:
115:
111:
107:
103:
99:
94:
88:
80:
79:chronological
76:
75:Julian period
71:
69:
65:
61:
56:
52:
45:
41:
37:
33:
19:
4861:Decimal time
4614:
4590:Astronomical
4469:Complication
4464:Atomic clock
4117:. Retrieved
4081:
4057:
4033:
4025:. Media Lab.
4022:
3998:
3981:
3973:
3960:
3950:
3946:
3932:
3921:
3905:
3891:
3884:
3874:
3870:
3860:pages 69–143
3857:
3832:
3812:, Washington
3808:
3781:
3777:
3762:
3752:
3733:
3721:
3705:
3694:
3687:
3684:
3667:
3652:
3635:
3632:McCarthy, D.
3623:
3600:
3596:. Brainsoft.
3593:
3582:
3575:
3560:
3551:
3537:
3518:
3507:
3498:
3487:
3473:
3470:
3459:
3453:(in English)
3448:
3440:
3432:
3420:
3406:
3388:
3367:
3353:
3346:
3342:
3331:
3321:
3289:
3281:
3274:
3270:
3247:
3244:
3239:
3223:
3204:
3190:
3171:
3153:
3142:
3134:
3115:
3106:
3097:
3088:
3079:
3070:
3061:
3052:
3043:
3034:
3025:
3020:Burgess 1860
3016:
3000:
2991:
2982:
2977:Laplace 1823
2973:
2965:
2961:
2953:
2949:
2944:1879, p. 494
2941:
2937:
2929:
2925:
2920:Winlock 1864
2916:
2907:
2898:
2889:
2880:
2871:
2866:" on p. 198.
2856:
2847:
2838:
2817:
2808:
2800:
2796:
2775:
2770:Depuydt 1987
2766:
2725:
2677:
2629:
2596:
2581:
2576:Collins 1666
2572:
2563:
2554:
2545:
2536:
2527:
2518:
2511:
2503:
2494:
2486:
2478:
2469:
2460:
2445:
2436:
2427:
2418:
2410:the original
2402:
2393:
2385:
2378:. Retrieved
2364:
2350:
2336:
2328:
2324:
2303:
2294:
2285:
2273:
2245:
2224:
2211:
2202:
2193:
2188:Grafton 1975
2184:
2176:
2172:
2163:
2140:
2127:
2118:
2108:
2075:
2045:Ordinal date
2008:Decimal time
1972:
1955:
1952:
1943:
1933:
1929:
1925:
1924:
1918:
1914:
1910:
1906:
1902:
1898:
1894:
1890:
1884:
1880:
1876:
1872:
1868:
1862:
1858:
1854:
1849:
1845:
1841:
1837:
1832:
1828:
1824:
1820:
1815:
1811:
1807:
1803:
1797:
1792:
1788:
1784:
1780:
1776:
1772:
1767:
1762:
1758:
1754:
1749:
1739:
1731:
1721:
1713:
1703:
1695:
1685:
1677:
1667:
1659:
1649:
1641:
1611:
1607:
1602:" indicates
1599:
1595:
1591:
1589:
1523:
1519:
1513:
1509:
1507:
1504:
1443:
1435:
1429:
1425:
1420:
1416:
1406:
1402:
1400:
1296:real numbers
1293:
1278:
1265:
1259:
1249:
1243:
1236:
1225:
1221:
1196:
1193:
1176:water clocks
1164:
1144:astronomical
1131:
1126:
1122:
1117:
1113:
1109:
1105:
1103:
1098:
1089:
1081:
1067:
1058:
1052:
1044:
1038:
1024:
1010:
1002:
1000:
984:
952:
947:
944:John Collins
942:
937:
933:
929:
927:
922:
918:
914:
902:
890:
886:
882:
878:
874:
870:
868:
862:
852:
846:
809:
798:
777:proposed by
774:
770:
768:
673:
630:
617:
590:
568:
549:
528:
504:
475:
451:
427:
402:
379:
356:
347:Modified JD
338:
320:
304:Julian date
291:Calculation
269:
264:
262:
254:
245:leap seconds
210:
205:
202:Julian years
190:ordinal date
185:
183:
153:(JD) of any
150:
148:
106:4713 BC
97:
95:
74:
72:
59:
57:
55:
40:Calendar Man
36:Ordinal date
4871:System time
4866:Metric time
4585:Solar Hijri
4511:Water clock
4494:Radio clock
4426:Time domain
4406:Proper time
4292:Leap second
4174:Chronometry
4047: 1963
3853: 1988
3349:, page 324.
3320:." (n.d.).
3145:, Page 122.
3047:Schram 1908
3038:Schram 1882
2986:Pogson 1860
2911:Peirce 1853
2741:remainder 1
2693:remainder 1
2645:remainder 1
2589:by Collins
2454: 1988
2380:January 14,
2266: 1963
2081:Anno Domini
2003:Dual dating
1976:leap second
1606:, and "mod(
1162:, in 1890.
1097:appears in
1088:in the new
1086:ephemerides
964:concurrents
790:lunar cycle
786:solar cycle
662:ephemerides
529:53582.29463
465:Lilian date
452:24372.83889
428:27294.83889
403:45557.33889
357:60576.83889
339:60577.33889
329:Reduced JD
186:Julian date
180:Terminology
151:Julian date
64:astronomers
18:Julian Date
4922:Chronology
4901:Categories
4886:Timekeeper
4839:Chronology
4823:Millennium
4709:Precession
4615:Julian day
4436:T-symmetry
4297:Solar time
4267:Civil time
4119:August 30,
3883:. (1997).
3649:Meeus Jean
3592:. (n.d.).
3465:(in Latin)
3139:(in Latin)
3009: 150
2803:, col. 705
2567:Gauss 1801
2558:Gauss 1966
2156:References
2085:Common Era
1744:−38
1184:Babylonian
1070:astronomer
993:in 5509/08
838:4256 + 457
728:Common Era
688:, in 1955.
550:1727122081
511:Common Era
393:Dublin JD
239:(TCB), or
60:Julian day
4783:Fortnight
4630:Lunisolar
4620:Leap year
4554:Gregorian
4504:stopwatch
4479:Hourglass
4459:Astrarium
4376:Spacetime
4307:Time zone
4184:Metrology
4163:standards
4036:. author.
3953:: 289–358
3873:, volume
2473:IBM 2004.
2464:Ohms 1986
2431:Chi 1979.
2374:Microsoft
1783:+ (((4 ×
1633:variable
1627:variable
1348:−
1281:proleptic
1262:proleptic
1203:Kali Yuga
1158:, of the
887:Remainder
879:Indiction
840:was thus
834:1 BC or 0
821:1 BC or 0
817:(JP) 4713
751:from the
724:Christian
678:January 0
603:DateTime
539:Unix time
192:) in the
184:The term
118:Indiction
66:, and in
4844:Duration
4818:Saeculum
4798:Olympiad
4640:Solstice
4569:Holocene
4546:Calendar
4446:Horology
4237:ISO 8601
4232:ISO 31-1
4091:citation
3818:citation
3690:311−313.
3605:Archived
3366:(2008).
3307:Archived
3195:Archived
3004:Ptolemy
2599:2+ until
1986:See also
1953:Example
1526:, 7) + 1
1180:Egyptian
1094:18 51 48
896:—
891:Quotient
792:) × 15 (
788:) × 19 (
704:Rata Die
489:Rata Die
441:CCSDS JD
411:in 1955
388:in 1979
365:in 1957
251:Variants
68:software
4813:Century
4803:Lustrum
4733:Instant
4605:Equinox
4574:Islamic
4516:Sundial
4381:Chronon
3977:. NASA.
3786:Bibcode
3725:. NASA
3482:2504611
3215:. Also
3141:, Tome
3126:Sources
3011:, p. 12
2736:
2721:
2715:
2703:
2688:
2673:
2667:
2655:
2640:
2625:
2619:
2607:
2449:Ransom
2146:Fortran
1861:)) div
1857:= (mod(
1726:274277
1522:= mod (
1446:+ 1, 7)
1218:3102 BC
1214:JP 1612
1171:Ptolemy
1062:4713 BC
968:1 2 3 4
842:JP 4713
801:4713 BC
760:History
730:in the
686:Ireland
654:Goddard
643:OpenVMS
639:IBM 704
637:via an
635:Sputnik
417:CNES JD
231:(TAI),
155:instant
91:AD 3268
4808:Decade
4763:Moment
4758:Minute
4753:Second
4723:Other
4580:Julian
4559:Hebrew
4205:offset
4064:
4005:
3990:
3912:
3898:
3839:
3769:
3740:
3712:
3674:
3659:
3642:
3626:vol. 5
3570:2004.
3544:
3480:
3376:
3362:&
3296:
3230:
3211:
3182:
3164:
2133:
1932:, and
1917:) div
1871:= mod(
1831:) div
1823:= mod(
1636:value
1630:value
1378:second
1365:minute
1207:Ujjain
1025:Julian
1003:Julian
995:
980:
976:
972:
928:where
921:+ 4845
917:+ 4200
885:: The
805:year 1
716:Python
682:Dublin
505:739152
476:161417
299:Notes
235:(TT),
124:, and
85:. The
4849:music
4788:Month
4748:Jiffy
4743:Shake
4738:Flick
4635:Solar
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