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Re: Parallax of Right Ascension and Parallax of Declination
From: Dave Walden
Date: 2015 Nov 2, 13:43 -0800
From: Dave Walden
Date: 2015 Nov 2, 13:43 -0800
To first order, the earth is a sphere. For a spheroid, in addition to the usual parallax in altitude, there is parallax in azimuth.
For precise parallax in RA/Dec, this should be considered.
You may recall that it was just this effect which led me to maintain that one can calculate, time, latitude, and longitude from three ultra-precise
lunar distances as we discussed some time ago.
From: Dave Walden
Date: 2015 Nov 1, 07:24 -0800
To first order, take usual parallax and rotate to the RA/Dec frame.
From: Herbert Prinz
Date: 2015 Nov 1, 23:06 -0800
Why do you say to first order? Isn't that exactly it?
