This series in tandem with the "Astronomy 162" course are among my favorite podcasts. I am thankful that Professor Pogge made his lectures available in this format. I've benefited greatly from listening to them. The subject matter is fascinating and Professor Pogge skillfully renders even the more difficult concepts accessible and understandable to a lay audience. His depth of scientific and historical knowledge is obvious, and his enthusiasm is infectious. An aspect of the presentation that appeals to me is that he does not play "hide the ball." Rather, he clearly and effectively explains things, in marked contrast to other astronomy podcasts that I've listened to. In fact, as I listen to these lectures it's become increasingly apparent to me that I am actually understanding many critical concepts for the first time. That's because the building blocks of knowledge that are essential to any real understanding of these topics are laid out so well, and build upon one another. I learned a whole bunch of new stuff and I also found that many questions that I had in the fore and back of my mind were addressed and answered. Professor Pogge is a gifted teacher. Enjoy.