Sun Azimuth (when used with Sun Elevation) is an angular coordinate system for locating the sun’s positions in the sky. Azimuth is measured clockwise from true north to the point on the horizon directly below the sun. Elevation is measured vertically from that point on the horizon up to the sun. If you know the azimuth of the sun is 135° from north, and the elevation is 30°, you can look toward the southeast, about a third of the way up from the horizon to locate the sun. Because our planet rotates, azimuth and elevation numbers for the sun constantly changing with time and with the observer’s location on earth. A negative Sun Elevation places the sun’s location below the horizon.