UNIGLOBE AS A SUNDIAL

The Uniglobe can be used to tell time from the sun's position by orienting the earth globe so that the observer's position is at zenith, and the polar axis is pointing in the polar direction. See Figure 29. Place the pointer on the sun's position (determined from the ephemeris) and rotate the celestial globe until the pointer's shadow disappears (the pointer is then directly pointed at the sun). This establishes the orientation of the two globes for the particular day and hour. The time ring is now rotated to the particular time system desired:

Sidereal Time	24 on Vernal Equinox
Apparent Sun Time	12 on Sun's position (from ephemeris)
Mean Sun Time	12 on Mean Sun Position (from ephemeris)

The time at a particular observation point is now read at the intersection of the time ring and the earth reference line. (See Figure 30). (Nearest standard longitude for standard mean time, local meridian for local time, etc.).

Note that this method may be used to tell time using any celestial object on the celestial sphere. For instance, if Arcturus is in transit in Hawaii on May 1, then it is 2350 Hawaii Standard Time (150° W).