Satellite Right Acension and Declination Calculations

[isi]

Hi Everyone...

I really want to be able to calculate the RA/DEC of a Satellite from TLE data. For example, the International Space Station (ISS)

Can anyone help to point me in the direction of where to find the claculations I need to perform this conversion from TLE data to RA/DEC?

I would really appreciate any responses to help me solve this conversion calculation!

Many Thanks

 

[russ_watters]

I'm not sure how to do it, but would you rather just have the positions given to you? You can get alt-az positions from heavens-above.com

 

[isi]

May thanks for the reply.. but no I wish to calculate it! :)
heavens above is good and everything but it gives me no understanding :(
Anyone able to help with the calculation from TLE data to RA/dEC?

 

[cadnr]

I don't know, but all it would take is a litle trigonometry.

Have you read http://en.wikipedia.org/wiki/Orbital_elements ?

 

[D H]

isi,

You will first need to propagate the two or three line elements from the epoch time to the time in question. This is the hard part. Once you have accomplished that, the computation of right ascension and declination is fairly easy.

A paper from NORAD (http://celestrak.com/NORAD/documentation/spacetrk.pdf" ) describes several algorithms of various fidelity that you can use to propagate the state.