Unit vector to Right Ascension/Declination

AI Thread Summary
To convert a unit vector to right ascension and declination, the correct formulae are essential, as the initial formulas used may be incorrect. Right Ascension and Declination serve as spherical coordinates, where declination is akin to latitude and right ascension to longitude. Resources such as Wikipedia and academic papers on positional astronomy provide valuable insights and transformations related to these coordinates. Understanding the metric tensor and its relation to the Jacobian transformation can aid in deriving accurate results. Ensuring the use of the correct formulas is crucial for successful conversion.
Scott S
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OK, I'm really rusty on this.

I need to convert a unit vector to right ascension and declination.
I believe I recall the formulae correctly, as I seem to have gotten 1 as my radius.
So, that's good.

In the pic I have my unit vector (P2), my actual answer below, my expected answer in red and the formulae I (believe) I need in blue shaded cells.

Any help greatly appreciated.
 

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Hey Scott S.

Can you point out a wiki or some other resource that outlines the concept you are talking about for ascension and declination?
 
A quick google search gave me this which discusses a lot of common transformations.

http://www2.astro.psu.edu/users/rbc/a501/positional_astronomy.pdf

If you wanted to derive the results yourself you should derive the metric tensor that goes between two systems and check if the tensor you derive gives the same results.

The metric tensor is related to the Jacobian transformation between the two systems and you can learn it by reading about tensor mathematics or differential geometry.
 
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Got it, thanks.

Wrong formulae.
 

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