Julian Date Converter
Convert standard Gregorian calendar dates into astronomical Julian Day Numbers (JDN).
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About Julian Dates
What is a Julian Day Number (JDN)?
The Julian Day Number is a continuous count of days elapsed since noon Universal Time on January 1, 4713 BCE, widely used by astronomers.
Why do astronomers use Julian dates?
JDN eliminates the complexities of varying month lengths, leap years, and calendar system transitions, making interval calculations straightforward.