Hour angle Negative hour angles indicate the time until the next transit across the meridian; an hour angle of zero means the object is on the meridian. Observing the sun from earth, the solar hour angle is an expression of time, expressed in angular measurement, usually degrees, from solar noon. At solar noon the hour angle is 0.000 degree, with the time before solar noon expressed as negative degrees, and the local time after solar noon expressed as positive degrees. For example, at 10:30 AM local apparent time the hour angle is -22.5° (15° per hour times 1.5 hours before noon). The
Type 90 75 mm field gun and Battle of Okinawa, often deployed together with armored units. The Type 90 continued to be used as field artillery until the surrender of Japan. The Type 90 formed the basis for the Type 3 75 mm tank gun used in the Type 3 Ho-Ni III Gun tank and Type 3 Chi-Nu medium tank. Type 90 75 mm field gun The was a field gun used by the Imperial Japanese Army during the Second Sino-Japanese War, Soviet-Japanese Border Wars and World War II. The Type 90 designation was given to this gun as it was accepted in the year 2590