June Second Saturday: Astronomy with David Whelan

Details:  There are certain things that we can directly measure for stars, such as their distances and brightnesses. Much of what else we think we know, for instance about their sizes, masses, surface temperatures, chemical makeup, and internal properties, comes to us by inference. Eclipsing binary star systems can offer us (almost) direct physical insight into the sizes and masses of stars, which can in turn help us understand the observable properties of similar stars more generally; even non-eclipsing binary stars are useful for deducing physical properties. Dr. Whelan will illustrate these points both from an historical perspective and by using recent discoveries made at Adams Observatory.

Bio: Dr. David Whelan is a stellar astronomer at Austin College. His research focuses on trying to understand the nature of intermediate- and high-mass stars -- stars for which little remains known their physical nature and evolution. Unraveling these mysteries requires use of the Adams Observatory, where he concentrates on observing stellar spectra for classification and quantitative analysis. He earned his M.S. and PhD degrees at the University of Virginia, and previously worked as a researcher and software programmer for the Spitzer Space Telescope mission, with the Infrared Spectrograph team at Cornell University.