NavList:

Byron: The Star Finder is a planning tool and not ment to be perfect, the accuracy should be good for ID and rough measurement of time so that the Navigator can plan to be in place and know where, when and who or what to look for.The accuracy is always a question so the time to be in place is broad, the Navigator must be early, for the question of the right time for occurance of a celestial sight depense on so many factors. I developed my star finder while in the Navy in the 1970ty. At that time I added a disk that was used for Sun rise,LAN, Set. I called it the family of horizons. I still have the disk, but stoped using it. The family of Horizons had the shape of all the horizons from 5N to 85 N and encluded the DEC for the months of the year and EQ of time. The Family of Horizons would be placed on the Base Disk,The plotting disk on top to be rotated freely. You interpolated between the Months DEC marking the free disk and rotated it to the horizon,DR. and read the time off the base.
It was supprizingly accurate, but you still better be on station at least 10 minute early. You could put the Long on your DR to get GMT or on Greenwich and your differce in degrees to get LMT.

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