pvlib.solarposition.sun_rise_set_transit_geometric(times, latitude, longitude, declination, equation_of_time)[source]

Geometric calculation of solar sunrise, sunset, and transit.


The geometric calculation assumes a circular earth orbit with the sun as a point source at its center, and neglects the effect of atmospheric refraction on zenith. The error depends on location and time of year but is of order 10 minutes.

  • times (pandas.DatetimeIndex) – Corresponding timestamps, must be localized to the timezone for the latitude and longitude.

  • latitude (float) – Latitude in degrees, positive north of equator, negative to south

  • longitude (float) – Longitude in degrees, positive east of prime meridian, negative to west

  • declination (numeric) – declination angle in radians at times

  • equation_of_time (numeric) – difference in time between solar time and mean solar time in minutes


  • sunrise (datetime) – localized sunrise time

  • sunset (datetime) – localized sunset time

  • transit (datetime) – localized sun transit time


[1] J. A. Duffie and W. A. Beckman, “Solar Engineering of Thermal Processes, 3rd Edition,” J. Wiley and Sons, New York (2006)

[2] Frank Vignola et al., “Solar And Infrared Radiation Measurements,” CRC Press (2012)