I will confirm that Sally Ride is
not a Pi Beta Phi-- our recent issue of the Arrow had a feature that confirmed (or dispelled) myths about famous individuals who are/ were Pi Beta Phi members and the website has a complete listing. We'd be proud to claim Sally Ride, if she really was a member but she isn't.
Since someone else mentioned Suzanne Sugarbaker (you can feel free to duck if you so desire but I'm not throwing anything), she did say she is a Mississippi Beta Pi Phi... that is the chapter at Ole Miss. While she IS a fictional character, the show's use of a trademarked name and accurate identification of a chapter must have been with consent-- the reference is included among the 'facts'. Mrs Parker and Mrs. Wrigley were NOT Pi Phis... their husbands just liked arrows