During the COVID-19 pandemic, informal learning environments (ILEs) were forced to move programming online for the safety of staff and visitors. The Big Astronomy Project responded to the pandemic by releasing a planetarium show as a virtual YouTube 360 stream. This project was also utilized in the late stages of the pandemic in-person at planetarium theaters, offering an opportunity for comparison between two modalities of showing a planetarium program. In general, ILEs often have a clear ambition to spark interest and support existing interest in order to support continued engagement after a visit. We use the four-phase interest model to characterize and compare audience's prior interest levels between a virtual and in-person environment. We used focus groups and interviews with audience members consisting of 46 individuals across the 2 modalities. We found that the individuals who watched the show virtually tended toward later phases of interest compared to those who watched the show in-person. We also explore how different audiences rated their level of interest. Based on these results we suggest that the virtual and in-person activities may need to be targeted to different audience interest levels.