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A library using formulae by Jean Meeus and NOAA to precisely determine various solar metrics.
Values from mean anomaly to zenith angle and sunrise/sunset times can be calculated, based on observer time and location.
Maintainer: Christian Menne
This library is compatible with all architectures so you should be able to use it on all the Arduino boards.
To use this library, open the Library Manager in the Arduino IDE and install it from there.