When looking for a formula to convert polar ecliptic geocentric coordinates of an object to equatorial coordinates I find various sources that give these formulae (like Wikipedia):
Declination $δ = arcsin(cos ε * sin β + sin ε * cos β * sin λ)$
Right ascension $α = arctan((cos ε * sin λ - sin ε * tan β) / cos λ)$
Where
β = ecliptic geocentric latitude
λ = ecliptic geocentric longitude
ε = obliquity of the ecliptic
But when applying these formulae I get results like in the following list where β = 0° and ε = 23.4°:
λ δ α
0 0.0000 0.0000
45 16.3095 42.5443
90 23.4000 90.0000
135 16.3095 -42.5443
180 0.0000 -0.0000
225 -16.3095 42.5443
270 -23.4000 90.0000
315 -16.3095 -42.5443
360 -0.0000 -0.0000
The values for declination seem good, but right ascension values seem to lack some sort of adjustment to the quadrant of the full circle (just a guess). But nowhere did I find any mentioning of this. Can you help? Thanks.
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