Ha spectroscopic obs. of Pleione from 2005-2019

Using the radiative transfer code hdust, we created a grid of ~100,000 disk models for Pleione. We successfully reproduced the observed transition with a disk model that varies in inclination while maintaining an equatorial density of {rho}_0_(r)=3x10^-11^(r/R_eq_)^-2.7^g/cm^3^, and an H{alpha}-emitting region extending to 15R_eq_.

We use a precessing disk model to extrapolate the changing disk inclination over 120 yr and follow the variability in archival observations. The best-fit disk model precesses over a line-of-sight inclination between ~25{deg} and ~144{deg} with a precessional period of ~80.5yr. Our precessing models match some of the observed variability but fail to reproduce all of the historical data available.