Grand Master Astronomical clock measures six feet tall and five feet wide. Made on commission by Art Donovan, much of the clock was hand built over a period of three months. Components on the solid mahogany body are held by oversized hand machined brass bolts.
A moon clock sits in the center and is backlit with hand-painted phases of the moon. To the right of the clock are two special clocks, the top one calibrated to show the time light from the moon takes to reach the earth (1.25 seconds), and the next one to show the time light takes to reach earth from the sun (8.3 minutes).