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Re: Modern Lunars
From: Paul Hirose
Date: 2016 Sep 26, 20:34 -0700

On 2016-09-25 22:08, Antoine Couëtte wrote: > Also are my Apparent Equatorial Coordinates from the Bureau des Longitudes Server the same as the ones you are obtaining on your side ? Maybe this should be the very first point to check again together this time. I am using the following ones (*before* performing the +0.50"/-0.25" correction earlier mentioned): > *Moon, 1855-09-07T08:05:00.00, i.e. 08h05m00.000 s TT : RA = 08 h 10 m 10.16146 s , DEC = +25 *°* 17 ' 31.0209 ", Distance = 0.002701090 UA,* There are some discrepancies: 08 10 10.16146 +25 17 31.0209 Bureau des Longitudes 08 10 10.1690 +25 17 31.006 JPL HORIZONS 08 10 10.196 +25 17 30.96 me DE406 08 10 10.195 +25 17 30.97 me DE422 Does Bureau des Longitudes still use the IAU 1976/80 precession nutation model? JPL does, but corrected with the pole offsets from the IERS in recent epochs. I don't know what corrections they apply in the 19th century. I use the IAU 2006/00A precession nutation model. I also have the 1976/80 model. However, my results are almost 2 arc seconds from JPL, so I'm doing something wrong.

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