Scientists have long sought to engage public audiences in research through citizen science projects such as biological surveys or distributed data collection. Recent online platforms have expanded the scope of what people-powered research can mean. Science museums are unique cultural institutions that translate scientific discovery for public audiences, while conducting research of their own. This makes museums compelling sites for engaging audiences directly in scientific research, but there are associated challenges as well. This project engages public audiences in contributing to real research as part of their visit to a museum. We present the design and evaluation of U!Scientist, an interactive multi-person tabletop exhibit based on the online Zooniverse project, Galaxy Zoo. We installed U!Scientist in a planetarium and collected video, computer logs, naturalistic observations, and surveys with visitors. Our findings demonstrate the potential of exhibits to engage new audiences in collaborative scientific discussions as part of people-powered research.