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Re: equinox
From: Trevor Kenchington
Date: 2004 Mar 21, 09:26 +0000
From: Trevor Kenchington
Date: 2004 Mar 21, 09:26 +0000
Fred, Of course you are right. Having converted the time from GMT to LMT for 72degrees West, in order to respond to your original longitude figure, I ended up looking in the almanac for GHA under 0248, which was the zone time of the equinox for my time zone (Z+4) -- and hence the first time I had seen quoted, long before your first posting. A very silly mistake. The almanac makes the GHA for 0648 GMT on March 20 as 280degress 8.4'. I suspect the difference from your figure is the rounding error in the almanac's estimate of the instant of zero declination. So I agree with your longitude -- which is that of Colombo (Sri Lanka) or Madras. While correcting my mistakes: I previously described 139degrees 52.3' East as approximately the longitude of Adelaide, which it is. Had I been a bit less anglo-centric, I should have noted that it is also the approximate longitude of Tokyo. Trevor Kenchington You wrote: > I get a GHA of 280degrees 8.56', which would be a longitude of > 79degrees 51.44' East. -- Trevor J. Kenchington PhD Gadus@iStar.ca Gadus Associates, Office(902) 889-9250 R.R.#1, Musquodoboit Harbour, Fax (902) 889-9251 Nova Scotia B0J 2L0, CANADA Home (902) 889-3555 Science Serving the Fisheries http://home.istar.ca/~gadus