You might persue looking at a Physics major with an Astronomy minor. I've worked with a lot of astronomers and they all recommend going this route. When you get to the PHD level is when you specialize in Astronomy. There are a couple of internet based degrees that take you to the Masters level, however, I don't know how credible these are in the real world. They are sites located in Australia and advertised in the astronmy magazines. Hope this helps!

Clear Skies Eric