Solar Position Chart in Cartesian Coordinates
This Demonstration charts the position of the Sun at a given time for a given location on Earth, expressed in Cartesian coordinates.[more]
Locations on Earth are defined by latitude and longitude. The time is defined by the mean solar clock a number of days after January 1. The position of the Sun is defined by its altitude in the sky and its azimuth angle along the horizon. This chart shows the horizon dividing the sky into day and night. You can see the path of the Sun during one full day, the solar paths for the solstices and equinoxes, and the analemma for the selected location.[less]
Time zones are calculated from longitude.
snapshot 1: at the equator
snapshot 2: at the North Pole
snapshot 3: in the Southern Hemisphere
The equations used for declination and equation of time are from .
The equations used for altitude and azimuth are from .
U.S. National Oceanographic and Atmospheric Administration. "General Solar Position Calculations." (Jan 31, 2012) www.srrb.noaa.gov/highlights/sunrise/solareqns.PDF.
U.S. Naval Observatory. "Computing Altitude and Azimuth from Greenwich Apparent Sidereal Time." (Jun 14, 2011) aa.usno.navy.mil/faq/docs/Alt_Az.php.