Need help with some coordinates

[the_id]

I am trying to write a Fortran program to convert B1950 Right Ascension/Declination to J2000 numbers. I’m having great difficulty finding reliable formulae. Most seem fairly accurate for near-equatorial coordinates. But the closer you get to the poles, the more inaccurate they become.<br /><br />Does anyone have any idea where I might find an accurate algorithm or is there no such thing?<br />

 

[MeteorWayne]

I'll ask around in meteorland.<br /><br />Can I ask why you need to covert the coordinates? <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[the_id]

Sorry to be so long in replying. After posting this morning, I got busy on another project and I’m just now getting a chance to check back.<br /><br />I’m developing a non-heliocentric galactic coordinate system. Essentially, I want to build a database of celestial bodies using the new coordinates. And I was surprised to learn that some large catalogues still give the RA/Dec in the B1950 epoch.<br /><br />Mostly, I just want the database to be as complete as possible. The initial goal is to convert all the coordinates to J2000 equatorial then to ecliptic and finally to my new galactic system -- which I’m calling Messier Zero. Well, actually, M0 would be the Milky Way galaxy. But since it’s the basis for the system, that’s what I’m calling the system, too.<br /><br />By the way, love your sig line. It's the basis for my nick.

 

[chode]

I did a quick google and found this:<br /><br />http://www.mathworks.com/access/helpdesk/help/toolbox/aeroblks/index.html?/access/helpdesk/help/toolbox/aeroblks/besselianepochtojulianepoch.html&http://www.google.com/search?sourceid=navclient&ie=UTF-8&rls=DVXA,DVXA:2005-37,DVXA:en&q=besselian+julian+conversion<br /><br />I have no idea if this is accurate, but it looks like it's worth testing out.<br /><br />EDIT: Here's another link that might be useful:<br /><br />http://star-www.rl.ac.uk/star/docs/sun67.htx/sun67.html<br /><br />Regards

 

[the_id]

Thanks. I'll have a look.