Computing Sunrise and Sunset in One Step
Stephen P. Morse, San Francisco

CHOOSE A DATE:            

CHOOSE A TIMEZONE: Either specify the time difference from Greenwich, or select the name of a timezone
hours minutes
of Greenwich
Convert to Daylight Saving Time

CHOOSE A LOCATION: Either specify the longitude and latitude, or select the name of a city
degrees minutes seconds
Latitude of the Equator
Longitude of Greenwich
First select a region
Then select a state
Finally select the city

sunrise       solar noon       sunset       errors

My original algorithm assumed a circular orbit and was therefore inaccurate
Current algorithm is derived from code appearing at
Lists of longitudes and latitudes and of world time zones were derived from tables at

© Stephen P. Morse, 2003