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Things We Don’t Understand About RR Lyrae Stars


Horace A. Smith
Michigan State University, Department of Physics and Astronomy, East Lansing, MI 48824

Presented at the 100th Annual Meeting of the AAVSO, October 8, 2011; received January 26, 2012; accepted January 26, 2012


RR Lyrae stars have been identified as a distinct class of variable star for slightly longer than the century the AAVSO has existed as an organization. Although considerable progress has been made in understanding RR Lyrae variables over the past century, several aspects of their pulsation remain puzzling. This paper reviews some of the more poorly understood properties of these pulsating variable stars, with emphasis on the contributions that might be made by observers associated with the AAVSO and similar organizations.

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