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Eclipsing Binaries in the 21st Century—Opportunities for Amateur Astronomers


Edward F. Guinan
Scott G. Engle
Edward J. Devinney

Department of Astronomy and Astrophysics, Villanova University, Villanova, PA 19085

Invited review paper, received June 5, 2012


Eclipsing binaries play major roles in modern astrophysical research. These stars provide fundamental data on the masses, radii, ages, atmospheres, and interiors of stars as well as serving as test beds for stellar structure and evolution models. The study of eclipsing binaries also returns vital information about the formation and evolution of close binaries themselves. Studying the changes in their periods from the observations of eclipse timings provides insights into evolution of close binaries, mass exchange and loss, apsidal motion for eccentric systems, as well as the discovery of the low mass (unseen) third bodies. Moreover eclipsing binaries in clusters and other galaxies can provide accurate distances to the star clusters and galaxies in which they reside. More recently observations of eclipsing exoplanet-star systems (that is, transiting exoplanets) when coupled with spectroscopy are yielding fundamental information about the frequency and the physical properties of planets orbiting other stars. For the reasons discussed above, observations of eclipsing binary systems have been popular for AAVSO observers and many papers have been published (see Williams et al. 2012, JAAVSO 40, No. 1). A recent example is the highly successful AAVSO’s Citizen Sky Project focused on the enigmatic long-period eclipsing binary ε Aur. Building on the success of the AAVSO during the last century, this paper explores the present and future prospects for research in eclipsing binaries. We focus on what can be done by AAVSO members and other amateur astronomers in the study of eclipsing binaries. Several examples of observing strategies and interesting (and scientifically valuable) projects are discussed as well as future prospects. As discussed, there are many opportunities for AAVSO members to contribute to the study of eclipsing binary stars and an increasing variety of objects to observe.

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