[amsat-bb] another question

[skristof at etczone.com]

My head filled up with questions today, so I'm trying to get a few out
to the folks who know the answers. 

First, Thanks to Jan for sending a copy of his presentation! 

My question: We can get data about voltages coming from X, Y, and Z
solar panels. I understand that X, Y, and Z are three spatial axes. 

But solar panels are planes. Are the panels oriented in a particular
plane (i.e. is the X panel in the X-Y plane or the X-Z plane) or do they
rotate around their particular axis? 

If they are fixed in one plane, is it standard for most satellites, or
does it vary from satellite to satellite? If it varies, how can we tell
which plane the solar panel is in? 

Are the axes always in the same orientation (e.g. is the Z axis always
pointed towards the Earth?)? 

If there is a book or other reference for these kinds of things, please
let me know.  

Thanks for your thoughts!! 

Steve AI9IN