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Re: Julian Date formula for sun algorithm
From: Bob Bossert
Date: 2025 Sep 10, 11:37 -0700
From: Bob Bossert
Date: 2025 Sep 10, 11:37 -0700
If the question was already answered, my apologies. I didn't read through all of the replies.
When i convert from Julian to UTC and back, I used the website. https://aa.usno.navy.mil/data/JulianDate
If you are looking for a formula, the book Astronomical Algorithms (2nd edition was 1998), authored by Jean Meeus has one. In Julian Date chapter he shows test cases you can use once you've built your own solution or want to validate someone else's solution. It is widely available in libraries. You should easily be able to find a copy. He also documents a lot of other calendar and date related equations.
