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Calculating time based on solar position

  1. Apr 21, 2009 #1
    Hi everyone,

    How do I figure out the date and time given latitude, longitude, solar azimuth and solar altitude. Let's say the time is limited to the time of the year starting at the summer solstice and ending at the winter solstice, so that there is only one answer per sun position.

    This picture is motivating me: http://www.alternativephotography.com/articles/art108.html [Broken]

    There's a formula for the reverse problem here: http://squ1.org/wiki/Solar_Position_Calculator#Manual

    But, it doesn't seem that easy to get the forward version.
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Apr 21, 2009 #2


    User Avatar

    Staff: Mentor

    The time is easy - the sun completes a complete revolution about the compass every day: at midnight it is due north and at noon it is due south.

    Date is more difficult and is easiest to find via the altitude at noon, checked against a table or calculated for your latitude.
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