# Homing in on Polaris: A 7 M⊙ first-overtone Cepheid entering the instability strip for the first time

@article{Anderson2018HomingIO,
title={Homing in on Polaris: A 7 M⊙ first-overtone Cepheid entering the instability strip for the first time},
author={Richard I. Anderson},
journal={Astronomy and Astrophysics},
year={2018},
volume={611}
}
• R. Anderson
• Published 1 March 2018
• Physics
• Astronomy and Astrophysics
A recently presented HST/FGS parallax measurement of the Polaris system has been interpreted as evidence for the Cepheid Polaris Aa to be pulsating in the second overtone. An age discrepancy between components A and B has been noted and discussed in terms of a stellar merger. Here I show that the new parallax of Polaris is consistent with a simpler interpretation of Polaris as a $7 \rm{M}_\odot,$ first-overtone, classical Cepheid near the hot boundary of the first instability strip crossing…

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