This algorithm calculates the solar and lunar zenith and azimuth angles in the period from the year -2000 to 6000, with uncertainties of +/- 0.0003 degrees for the Sun and +/- 0.003 degrees for the Moon, based on the date, time, and location on Earth. The algorithm can be used for solar eclipse monitoring and estimating the reduction in solar irradiance for many applications, such as smart grid, solar energy, etc. The software has not been tested on a variety of platforms and is not guaranteed to work on yours. It is provided here as a convenience.
How to use this algorithm and a description of the variables is included in the
sampa.h header file. Further information on this algorithm is available in the following
NREL technical report:
Reda, I. (2010). Solar Eclipse Monitoring for Solar Energy Applications Using the Solar and Moon Position Algorithms. 35 pp.; NREL Report No. TP-3B0-47681. (927 KB PDF Document)
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Note: An online SAMPA calculator that uses this source code is also available.