Today's class began with a further discussion of the nature of light and continued with a lesson on stellar astronomy. The information packed day continued after lunch with a presentation about how optical and radio telescopes work, and how they are used by astronomers. Finally the day wrapped with a lecture about astrobiology, which will be explored in further detail next week when students present current astrobiology research and events. We walked/ rode up to the optical ridge (above the main "campus") for a view of PARI from the top. The day ended with an evening of games and home- made cookies.