Software for astronomy, calendars and date conversion

The Chinese Calendar: Dates of New Years, Dark Moons and Solar Terms Lunar Calendars and Eclipse Finder Easy Date Converter Equinoxes, Solstices and Cross‑Quarter Days BCE‑BC‑AD‑CE Converter Eclipses, Moon Phases and Seasons

The Chinese Calendar: Dates of New Years, Dark Moons and Solar Terms  Click on the title for the full description.
A program for the study of the Chinese Calendar. It convert between dates in various Chinese calendars and dates in the Gregorian and Julian calendars, and (among other things) finds lunar new year dates and leap months for any year in the Chinese Calendar.  Read more ...

Lunar Calendars and Eclipse Finder  Click on the title for the full description.
A program to search for eclipses (lunar, solar, total, annular and partial), to calculate the phase of the Moon at any given date and time and to convert between dates in the Gregorian and Julian calendars and dates in various lunar calendars: Meyer-Palmen Solilunar, Hermetic Lunar Week, etc.  Read more ...   Top

Easy Date Converter  Click on the title for the full description.
Adds a number of days or months to a date, calculates the number of days between two dates (with or without weekend days), and converts among Common Era (Gregorian) dates, Julian dates, ISO 8601 Week dates, Hermetic Leap Week dates, Julian day numbers and day-in-year dates of the form yyyy-ddd. Bilingual: English and German  Read more ...   Top

Equinoxes, Solstices and Cross‑Quarter Days  Click on the title for the full description.
Software to calculate accurate dates and times for equinoxes, solstices and the Celtic cross-quarter days. The cross-quarter days are those midway between the equinoxes and solstices. Works for both the northern hemisphere and the southern.  Read more ...   Top

BCE‑BC‑AD‑CE Converter  Click on the title for the full description.
Converts between calendar dates in BCE, BC, AD and CE date formats, and adds/subtracts a number of days, weeks, months and years to/from a given date.  Read more ...   Top

Eclipses, Moon Phases and Seasons  Click on the title for the full description.
Displays (over a range of years) the exact dates and times of partial, annular and total solar eclipses, of partial, penumbral and total lunar eclipses, of phases of the Moon, and of solstices, equinoxes and the solar cross-quarter days.  Read more ...   Top

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