My goal with these videos is to introduce topics in physics and astronomy at a level understandable at a high school / first year undergraduate level. I especially want to describe some of the observational evidence which support (or refute) our current theories of the universe.You can follow me on twitter at https://twitter.com/MichaelJKoopI'm also a member of the NANOGrav collaboration: http://nanograv.org/I am very interested to hear any comments, questions, or suggestions for topics. Please let me know what you think of these videos by filling out a short survey at http://tinyurl.com/astronomy-pulsar. Thank you.