1、Lessons Learned Entry: 0527Lesson Info:a71 Lesson Number: 0527a71 Lesson Date: 1994-08-25a71 Submitting Organization: LARCa71 Submitted by: Bernard LewisSubject: Producing a Symmetrically Smooth Time Base for Celestial Photography Description of Driving Event: Two Langley Research Center employees,
2、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 th
3、e 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 numbe
4、r in order to produce a signal that approximates sidereal time with an error of only about 1.8 seconds per year.Lesson(s) Learned: A symmetrically smooth time base for celestial photography can now be produced for standard 60 Hz power.Recommendation(s): A certificate and cash have been awarded for t
5、he disclosure and innovation entitled “Sidereal Rate Generator,“ LAR-14350-1.Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-N/AMission Directorate(s): N/AAdditional Key Phrase(s): a71 Research & DevelopmentAdditional Info: Approval Info: a71 Approval Date: 1997-04-02a71 Approval Name: Elijah C. Kenta71 Approval Organization: 421a71 Approval Phone Number: 757-864-3345Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-