Search results
Results From The WOW.Com Content Network
The Julian date (JD) of any instant 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. [8] For example, the Julian Date for 00:30:00.0 UT January 1, 2013, is 2 456 293.520 833. [9]
No guidance is provided about conversion of dates before March 5, -500, or after February 29, 2100 (both being Julian dates). For unlisted dates, find the date in the table closest to, but earlier than, the date to be converted. Be sure to use the correct column. If converting from Julian to Gregorian, add the
This template computes the number of the Julian day starting at noon on the date given in parameter (in the Gregorian calendar, without any Julian correction for proleptic Gregorian dates where the calendar was not effectively applied). The result is valid for all proleptic Gregorian calendar dates starting on March 1, 4800 BC (−4799) at ...
Note that Julian days begin at noon (hour = 12) and thus hours 0-11 of a solar day are one Julian day earlier than hours 12-23. The value may extend outside of the normal range and is considered as additional number of julian days (a Julian day is 24 hours or 86400 seconds exactly, ignoring any adjustment of leap seconds within the UTC calendar).
A calendrical calculation is a calculation concerning calendar dates. Calendrical calculations can be considered an area of applied mathematics. Some examples of calendrical calculations: Converting a Julian or Gregorian calendar date to its Julian day number and vice versa (see § Julian day number calculation within that article for details).
The Julian JDN column is Julian day number when the date is interpreted as a Julian date, and the Gregorian JDN column is the JDN when the date is interpreted as Gregorian date. The calculations were done in Excel; JDN was calculated using algorithms from chapter 12 of Seidelman's (1992) Explanatory Supplement to the Astronomical Almanac ...
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
Zeller's congruence is an algorithm devised by Christian Zeller in the 19th century to calculate the day of the week for any Julian or Gregorian calendar date. It can be considered to be based on the conversion between Julian day and the calendar date.