Director of the hayden planetarium, place we all went to as a kid and i was never the same after that. I came back and actually became director. We also want to welcome cspan into this event. They are recording it for book tv. Cspan inhouse. Pan is [applause] tonights book is called welcome to the universe. I love saying that, welcome to the universe. When you go to the planetarium director school, they teach you how to speak like that. Let me immediately introduce my coauthors. First, michael strauss. [applause] these are my two coauthors. [applause] have a seat so just a bit of an introduction, i talked fori t ten years at Princeton University from 1994 through 2003, and before i transferred all of my activities here to this museum, over that time, i taught a course on introductory astrophysics and i got very popular and people liked it and we moved to vickers pace and we realized we could charge, we could energize the course even more by adding other talent that has particular exper