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Do you know of any good reference projects to calculate sunrise and sunset times from NTP? (lemmy.world)

submitted 1 week ago by j4k3@lemmy.world to c/asklemmy@lemmy.world

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I'm specifically looking for small microcontroller implementations for a simple clock project. I want to use a good temperature compensated real time clock and/or network time protocol-only (no sunrise/sunset APIs), to calculate local solar noon, sun rise, and sunset times. Then I want to make my own local time where midnight/bedtime is simply 9 hours before sunrise on any given day. I am in special life circumstances where I have no real use for daily coordinated time. This is a little psychology experiment more than anything else. I'm super rusty on the math.

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[–] mp3@lemmy.ca 4 points 1 week ago* (last edited 1 week ago)

In order to calculate an accurate sunrise and sunset time, you need the following variables to be known.

The current day
The current time (if you want to know the time delta for when it rises and sets)
The current location

Also, we need to consider that NTP sends the time in UTC, and the timezone offset calculation is done by the endpoint.

Even if you know the timezone your in, it still doesn't provide the exact position you need to accurately determine when the sun will rise and set.