Easy Date Converter 

Adds a number of days to a date, calculates the number of days between two dates, and converts among Gregorian dates, Julian dates, Julian day numbers and ordinal dates of the form yyyy-ddd. Supports batch computation.
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Lunar Calendars and Eclipse Finder 

A program to search for eclipses (lunar, solar, total, annual and umbral), 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.
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