Our ongoing coverage of preparation for the Great American Eclipse takes us to Southern Illinois University Carbondale where a huge celebration is planned. Then we hear from two members of the team that wants you to do eclipse science in the Eclipse Megamovie Project. Senior Editor Emily Lakdawalla is back! She was at JPL when Cassini began the final phase of its Saturn journey. How many confirmed planets are there in our galaxy? Bruce Betts will answer that question and offer another space trivia quiz in What’s Up. Related links are here: http://www.planetary.org/multimedia/planetary-radio/show/2017/0503-eclipse-siu-adler.html