Explore: Hour Angle

celestial navigation, the hour angle is the dihedral angle between the meridian plane (containing Earth's axis and the zenith) and the hour circle (containing

\tan \delta } where: ω ∘ {\displaystyle \omega _{\circ }} is the solar hour angle at either sunrise (when negative value is taken) or sunset (when positive

to the hour circle passing through the object. Unlike right ascension, hour angle is always increasing with the rotation of Earth. Hour angle may be considered

and 180 degrees when the hour angle, h, is negative (morning) and the angle between 180 and 360 degrees when the hour angle, h, is positive (afternoon)

{\displaystyle \alpha _{s}=90^{\circ }-\theta _{s}} h {\displaystyle h} is the hour angle, in the local solar time. δ {\displaystyle \delta } is the current declination

thousands of years. Mean solar time is the hour angle of the mean position of the Sun, plus 12 hours. This 12 hour offset comes from the decision to make

official noon. This correction can easily be made by rotating the hour-lines by a constant angle equal to the difference in longitudes, which makes this a commonly

and hour angle at a specific location, modify the formula for a spherical Earth. Replace φ2 with declination and longitude difference with hour angle, and

angle. The sides divide the plane of the angle into two regions: the interior of the angle and the exterior of the angle. The interior of the angle is

average of Q over a day is the average of Q over one rotation, or the hour angle progressing from h = π to h = −π: Q ¯ day = − 1 2 π ∫ π − π Q d h {\displaystyle