- #1
cptolemy
- 48
- 1
Hi,
I'm programming a simple DLL to use VSOP87 and ELP82b.
I can get the correct x,y and z values without a problem referred to J2000, I think.
But I'm getting a constant error when applying the correction for the nutation and precession in ELP82b. Actually, I'm getting even worst values than the Lunar Tables from 4000BC to 8000DC of Chapront.
The precession is rather simple - and the nutation is just adding. But maybe I'm missing the correct algorithms to do so.
Any ideas - or sources - for this?
Kind regards,
CPtolemy
I'm programming a simple DLL to use VSOP87 and ELP82b.
I can get the correct x,y and z values without a problem referred to J2000, I think.
But I'm getting a constant error when applying the correction for the nutation and precession in ELP82b. Actually, I'm getting even worst values than the Lunar Tables from 4000BC to 8000DC of Chapront.
The precession is rather simple - and the nutation is just adding. But maybe I'm missing the correct algorithms to do so.
Any ideas - or sources - for this?
Kind regards,
CPtolemy