Being a political scientist, I can't claim to know the difference between mean and apparent solar time, but one of the relevant portions in the article says: "... so the greatest probability is that the 'Beijing Time' they were then using [ie before 1954] is not Beijing mean time (北京地方平时) but actual Beijing solar time (北京地方的真太阳时)" (p3). -Jonathan On Oct 18, 2010, at 9:30 PM, Tony Finch wrote:
On Sat, 16 Oct 2010, Jonathan Hassid wrote:
There is a longish discussion about whether Beijing time means local solar time or based on a GMT offset, and Guo argues that between 27 Sep 1949 and 1954 (date unspecified), "Beijing time" meant local Beijing solar time (with an offset varying by time of year of course, but generally between 46 and 56 minutes earlier than 120 degree latitude time).
That's surprising. It's easier to generate time signals based on mean solar time, not aparrent solar time.
Tony. -- f.anthony.n.finch <dot@dotat.at> http://dotat.at/ HUMBER THAMES DOVER WIGHT PORTLAND: NORTH BACKING WEST OR NORTHWEST, 5 TO 7, DECREASING 4 OR 5, OCCASIONALLY 6 LATER IN HUMBER AND THAMES. MODERATE OR ROUGH. RAIN THEN FAIR. GOOD.
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