The Harvard-Smithsonian Center for Astrophysics (60 Garden Street in Cambridge) will host a special event, March 31 , 6:30-9PM:  Do-It-Yourself Planet Hunting.   The free, participatory workshop is for adults and youth 14 years or older.  Learn how to control robotic telescopes and analyze images for evidence of exoplanets.  It’s fully booked, but you can get on the waitlist.