below you find the url of a very easy and neat Astronomy course by Dave Soper/U. Oregon. He is a well known particle theorist and a friend of mine.
Parts of the course also concern issues, some of us are presently discussing with lots of energy in the users dept.
: Binary star orbits, Color/Luminosity <==> Mass correlations and lots of other rather basic knowledge.
Clearly this is NOT for experts. That course can even be well digested with a (big) glass of beer or wine next to the compi
http://zebu.uoregon.edu/~soper/astr121.html
Enjoy
Fridger