This document defines various angles used to describe the position of the sun relative to Earth and vertical surfaces. It outlines three angles that describe the Earth's position: latitude, declination, and hour angle. It then defines three sun angles: inclination angle, zenith angle, and solar azimuth angle. Finally, it lists three surface angles: surface azimuth angle, tilt angle or slope, and angle of incidence.

1. Basic Earth-Sun Angle

2. Solar Angles
Describe the
sun position
relative to a
vertical
surface

3. Earth Angle
1.Angle of Latitude (Φ)
2.Declination (δ)
3.Hour Angle (ω)

4. 2.Declination (δ)

5. 3.Hour Angle (ω)

6. Sun Angle
1. Inclination Angle (Altitude) (𝛼)
2. Zenith Angle (θz)
3. Solar Azimuth Angle (γs)

7. Surface Angle
1.Surface Azimuth Angle (γ)
2.Tilt Angle or Slope (β)
3. Angle of Incidence (θ)