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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Russian data
From: Dave Walden
Date: 2021 Jun 30, 13:11 -0700
From: Dave Walden
Date: 2021 Jun 30, 13:11 -0700
http://iaaras.ru/en/dept/ephemeris/online/
russian data (and easy access to US and French as well)
if you get as far as topocentric, you need to think like a russian astronomer. I.e., coordinates are:
long
rho sin phi
rho cos phi
where phi is latitude.
recall WGS-84 constant:
earth flattening=1/298.257223563 (or 1-1/f = 0.996647189)
then, if u = atan( 0.996647189 tan phi)
we have:
rho cos phi = cos u
rho sin phi = 0.996647189 sin u
