- julian day calendar
- noun
Usage: usually capitalized J: a system used especially by astronomers of numbering days consecutively from the arbitrarily selected point of the year 4713 B.C. instead of by cycles of days
Useful english dictionary. 2012.
julian day calendar
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julian day number — noun Usage: usually capitalized J : the number of a day in the Julian day calendar (as 2,436,934 for January 1, 1960) … Useful english dictionary
Julian day — JDN redirects here. For the military IT system, see Joint Data Network. For the comic book character Julian Gregory Day, see Calendar Man. Not to be confused with Julian year (disambiguation). Julian day is used in the Julian date (JD) system of… … Wikipedia
Julian day — (JD) a continuous count of days beginning with January 1, 4713 BC ( 4712 CE), which is start of what is called the Julian period. The French scholar Joseph Justus Scaliger (1540 1609) introduced the Julian period in 1582 (the same year the… … Dictionary of units of measurement
modified Julian day — (MJD) a count of days used by astronomers, space agencies, and others. Astronomers have long used the Julian day, a count of days beginning at noon Universal Time January 1, 4713 BC, as a means of specifying a date independent of all calendars … Dictionary of units of measurement
CALENDAR — (Heb. לוּחַ, lu aḥ). The present Jewish calendar is lunisolar, the months being reckoned according to the moon and the years according to the sun. A month is the period of time between one conjunction of the moon with the sun and the next. The… … Encyclopedia of Judaism
Julian calendar — The Julian calendar began in 45 BC (709 AUC) as a reform of the Roman calendar by Julius Caesar. It was chosen after consultation with the astronomer Sosigenes of Alexandria and was probably designed to approximate the tropical year (known at… … Wikipedia
calendar — calendrical /keuh len dri keuhl/, calendric, calendarial /kal euhn dair ee euhl/, calendarian, calendaric, adj. /kal euhn deuhr/, n. 1. a table or register with the days of each month and week in a year: He marked the date on his calendar. 2. any … Universalium
Calendar — For other uses, see Calendar (disambiguation). For the Gregorian calendar for this year, see Common year starting on Saturday. A page from the Hindu calendar 1871–1872. A calendar is a system of organizing days for social, religious, commercial,… … Wikipedia
Calendar era — A calendar era is the year numbering system used by a calendar. For example, the Gregorian calendar numbers its years in the Western Christian era (the Coptic and Ethiopic churches have their own Christian eras, see below). The instant, date, or… … Wikipedia
Julian year (astronomy) — In astronomy, a Julian year (symbol: a) is a unit of measurement of time defined as exactly 365.25 days of 86,400 SI seconds each, totalling 31,557,600 seconds. That is the average length of the year in the Julian calendar used in Western… … Wikipedia
