Hi all, I just finished my first week of playing with, and getting to know my moonstick. I felt that the idea for it, the completeness of dates and calendar quirks, the appealing design of the hex-slide rule and workmanship were all superb! So was the professionalism in the purchase and delivery.
What I did find disturbing though, is that it too, like most sundials, has its variation in readings from "standard" ephemeris time. After playing with it and feeling like I could tell where the moon was on any date, I started telling my family where the moon was when they were born. This was quite fun. A few days later, I used it to check this last new moon, and found it to be off by about 12 hrs or more. It appears that this design is based on some ?"median" moon and sun position, which I guess most sticks like this are, and that this just happens to be about the most "off" it can get. Actually 16 Hrs off! I was crushed. I really wanted this slide rule to be able to tell me where the moon was in relation to the sun when I was entering the world. Sean Barton quickly answered my query to him about the inaccuracy. He directed me to his website "moonstick.com" where I found a page of tables and formulas, "Moon Phase Definition Conversions", for correcting the final reading. This definitely takes the joy out of using it, so I just hope I can learn to live with this inaccuracy. Another possibility which I'm perusing, is to try to understand where the error comes from. Then I will be more able to live with it, just as I now know how to roughly adjust a standard horizontal dial reading to allow me to see if it is "correct to my watch". I'm afraid that the nice, simple correction for longitude and yearly EoT will not be duplicated in 2,000 years of moon / sun relationships! It has still been a wonderful investment and learning experience, and I would highly recommend one to all; I would emphasize, though, that I am just a beginner and not an expert in this arena. Fritz Stumpges -----Original Message----- To: all Subject: Extra Moonsticks David Higgon London
