This article has an extra 71 sec, but it does not say exactly which day. On the other side it has a deffciency of 75 sec.
"Apparent solar time, sometimes called true solar time, is determined by the daily apparent motion of the observed Sun. It is based on the interval between two successive returns of the Sun to the local meridian. The length of a solar day varies throughout the year, and the accumulated effect of these variations (equation of time) produces seasonal deviations of up to 16 minutes. Why, you may ask: Earth's orbit is elliptical and the Earth's axial tilt. Consequently, apparent solar days are shorter in March (26-27) and September (12-13) than they are in June (18-19) or December (20-21). In 2010, the greatest Universal Time(UT1) interval between apparent midnights (at Greenwich) is 86,471 seconds and the shortest interval is 86,325 seconds." Ref. http://www.universetoday.com/14700/how-long-is-a-day-on-earth/ Tom _____ From: [email protected] [mailto:[email protected]] On Behalf Of Tom Laidlaw Sent: Wednesday, September 14, 2011 2:25 PM To: 'Marcelo'; 'Frank Evans' Cc: 'Sundial' Subject: RE: longest day According to a wi9kipedia article the longest Apparent Solar Day is Dec. 22 at 24 hrs. 29.9 sec. http://en.wikipedia.org/wiki/Solar_time#Apparent_solar_time Does it have a name? How about Longest Apparant Solar Day Tom Laidlaw _____ From: [email protected] [mailto:[email protected]] On Behalf Of Marcelo Sent: Wednesday, September 14, 2011 12:49 PM To: Frank Evans Cc: Sundial Subject: Re: longest day I used to think that the longest day was the summer solstice. Methinks that you refer to some effect from the Equation of Time. And I don't know if there is a name for it. 2011/9/14 Frank Evans <[email protected]> Greetings, fellow dialists, I tried to astonish my grandson by telling him that this was the longest day of the year. (I think this is correct; today is 24 hours and 22 seconds long.) He replied by asking if there was a name for this day. He said he couldn't find anything on the interwebs. I am being outplayed by a grandson! Any help with a name, please? Frank 55N 1W --------------------------------------------------- https://lists.uni-koeln.de/ <https://lists.uni-koeln.de/mailman/listinfo/sundial> mailman/listinfo/sundial
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