This year's spring meeting will begin on Thursday evening, May 5, at 6pm CDT (23:00 UT), with a keynote address by Dr. Horace Smith, Professor Emeritus of Michigan State University and a noted expert on RR Lyrae stars. Dr. Smith's talk will be accessible remotely, to anyone for free, via GoToWebinar. To register please go to : https://attendee.gotowebinar.com/register/5791902173743269122
The title of his talk is "Learning from Pulsating Stars: Progress over the Last Century"
Abstract: Scarcely more than a century has elapsed since it began to be widely accepted that pulsation plays an important role in the variability of stars. During that century pulsating stars have been used as tools to explore a variety of astrophysical questions, including the determination of distances to other galaxies, the testing of timescales of evolution through the HR diagram, and the identification of the ages and star formation histories of stellar populations.
Among the significant early milestones along this investigative path are Henrietta Leavitt's discovery of a relation between the periods and luminosities of Cepheids, Harlow Shapley's proposal that all Cepheids are pulsating stars, and Arthur Stanley Eddington's use of the observed period change of delta Cephei to constrain its power source. Today our explorations of pulsating stars are bolstered by long observational histories of brighter variables, surveys involving unprecedentedly large numbers of stars, and improved theoretical analyses. This talk will review aspects of the history and our current understanding of pulsating stars, paying particular attention to RR Lyrae, delta Scuti, and Cepheid variables. Observations by AAVSO members have provided insight into several questions regarding the behavior of these stars.
The AAVSO Membership Meeting will be held Saturday morning, May 7 at 9am CDT (14:00 UT). The purpose of this meeting is to inform attendees of the activities of the Association. The Director’s Report as well as reports from the Secretary and Treasurer will be included. All portions of the membership meeting will be broadcast online via GoToWebinar. To register for the webinar go to: https://attendee.gotowebinar.com/register/3872154871646526978