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Atomic Watch (was: Extremely poor conditions??)
From: Alexandre Eremenko
Date: 2012 Mar 21, 21:31 -0400
From: Alexandre Eremenko
Date: 2012 Mar 21, 21:31 -0400
Greg wrote: > digital atomic clocks jump a complete minute > on me out of the blue for no reason. Following Greg's insight, I added one ``leap minute'' to the time recorded by Bill's Atomic Watch and obtained these results: GMT 21:34, Astra, Sun. Errors: -1'5, -3'3, 0'1, 0'8, 3'8 Average: 0'0, sigma=2'3 GMT 21:46, Astra, Sun. Errors: 0'3, -0'3, -0'4, -0'3, -0'3 Average: -0'2, sigma=0'25 (Bill's series, our best of the day!) GMT 21:54, Astra, Sun. Errors: -0'8, -1'8, 1'6 Average: -0'3 GMT 22:38, Astra, Sun. Errors: -0'6, 2'2, 0'9, 0'1, 1'2, 0'6 Average: 0'7, sigma=0'9 GMT 23:46, Astra, Venus. Errors: 0'9, -0'6, 1'2, -1'6, -0'7 Average: 0'1, sigma=1'0 GMT 23:58, Astra, Venus. Error: 4'6 (This is Bill, chilled. Bill is a Sun specialist buts I compete with him in stars observations :-) Pocket sextant: GMT 22:14, Sun. Errors: -0'8, -3'2, -0'2, -3, -2'7 Average: -2'0, sigma=1'2 GMT 00:03, Venus Errors: -0'2, 1'0, 3'0 Average: 1'3 (Pocket sextant scale cannot be read to less than 1') What can I add? Well, maybe I have to explain how my analog watch was used (in the 4-th and 5-th series, when Bill went for a walk on the jetty). I measured altitude, then looked quickly at the watch, SECONDS only, subtracted one, and quickly recorded... Then I looked at the hour and MINUTE on the Atomic Watch which stood on a piece of concrete nearby next to my notebook, and recorded hours and minutes. Then I carefully read the scale and recorded the altitude. The reason I used such a procedure is that it really takes me some time to read the minute of my analog watch; the second and minute hands are not synchronized, as is the case even for very expensive watches, so I decided to take this shortcut using the Absolutely Precise Atomic Pocket Watch which bill left with me while going for a walk. What else? I sincerely thank all who participated in this vivid discussion. I really learned a lot of interesting things about dip and refraction. I mean it. But I still believe that the dip correction is always negative. Because I am sort of claustrophobic, and if it were positive on that day I'd definitely feel it, feel like being in a pit... Thanks again to everyone. And especially to Greg. Now I can at least sleep well, without this nightmares of being in a pit with positive dip correction:-) Alex.