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Polaris the Cepheid has been observed for centuries, presenting surprises andchanging our view of Cepheids and stellar astrophysics, in general.Specifically, understanding Polaris helps anchor the Cepheid Leavitt law, butthe distance must be measured precisely. The recent debate regarding thedistance to Polaris has raised questions about its role in calibrating theLeavitt law and even its evolutionary status. In this work, I present newstellar evolution models of Cepheids to compare with previously measured CNOabundances, period change and angular diameter. Based on the comparison, I showthat Polaris cannot be evolving along the first crossing of the Cepheidinstability strip and cannot have evolved from a rapidly-rotating main sequencestar. As such, Polaris must also be at least 118 pc away and pulsates in thefirst overtone, disagreeing with the recent results of Turner et al. (2013).

Revisiting the fundamental properties of Cepheid Polaris using detailed stellar evolution models