Julian day - Knowledge (XXG)

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

17: 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

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 2460573.8933218. 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 09:26, Friday, September 20, 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 2024-09-20 09:26:23 ( 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, 18:Modified Julian date 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 591:1.7268243830035E+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 618:638624211830035200 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: 569:1726824383004 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: 321:2460573.89306 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 529:53578.94099 465:Lilian date 452:24369.39306 428:27291.39306 403:45553.89306 357:60573.39306 339:60573.89306 329:Reduced JD 186:Julian date 180:Terminology 151:Julian date 64:astronomers 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:. 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