I am currently working on masters thesis that utilizes the Super Cosmos archives (http://surveys.roe.ac.uk/ssa/) to plot all the stars in our galaxy in a 3D space. The problem is I am no astronomer and to tell the truth a newbie in this field... I have been having a problem converting the given data in the databse to what I need, which is the cartesian cordinates of each stars (x, y, z). The only given data are the RA, DEC, the proper motions parrallel to the RA and the DEC. I need to convert (somehow) these values into cartesian coordinates (with proper depth as the given x, y, and z in the database form a celestial sphere around earth with no depth). I have been told that its possible to calculate the 3D cartesian vales with these attributes but the only information I could come up with after extensive research always included the use of the parallax or the red shift which unfortunately is not available to me.

Thanks a lot for helping out... Much appreciated : )