Long-Term Visual Light Curves and the Role of Visual Observations in Modern Astrophysics

Volume 40 number 1 (2012)

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John R. Percy

Department of Astronomy and Astrophysics, University of Toronto, Toronto, ON M5S 3H4, Canada; john.percy@utoronto.ca

Abstract

Thanks to organizations such as the AAVSO, visual observations of variable stars have scientific strengths: they are numerous, sustained, and standardized. Though many people have predicted the demise of visual observation, the demand for such observations increased dramatically in the last quarter of the 20th century. In addition to their value in detecting, timing, and studying outbursts in CVs, fadings in R CrB stars, and eclipses in binaries, they are uniquely useful in studying the behavior of pulsating stars, especially slow, irregular, and long-term behavior, and changes in period and amplitude. In this review, I give a general review of this topic, with some emphasis on my own work on pulsating red and yellow variables, and on T Tauri stars. Much of this work has been done by undergraduate students and outstanding high school students; I highlight the importance and potential of AAVSO visual data for educational use.