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Description of Driving Event:

Two Langley Research Center employees, Brad Leighty and John Franke, received a certificate and cash award for the disclosure of innovation entitled "Sidereal Rate Generator," LAR-14350-1. This circuit was developed to produce a symmetrically smooth time base for celestial photography from standard 60 Hz power. Normal time is based on the position of the sun. There are approximately 365.25 solar days in the year. A sidereal day is the average time between meridian crossings by a star. There are approximately 366.25 sidereal days in a year. This circuit multiplies standard 60 Hz power cycles and divides by a slightly different number in order to produce a signal that approximates sidereal time with an error of only about 1.8 seconds per year.