Sigma Xi Seminar Series
Sponsored by Sigma Xi The Scientific Research Honor Society
Presents:
Two is Better than One:
The Boon to Astrophysics of Binary Stars
by
Dr. Eugene F. Milone,
Emeritus Professor,
Department of Physics &Astronomy, University of Calgary
Thursday, November 16rd 2017, 5 pm
University of Calgary, Biological Sciences Room 211
Abstract: Double stars and variable stars have been recognized for at least as long as stars have been named, and the notion that some seemingly double stars were indeed in close proximity to each other probably originated early as well, but John Mitchell argued in 1767 that it was likely. The first use of the term binary star is attributed to William Herschel. In 1782 the young star-crossed astronomer John Goodricke suggested that the variability of Algol (the Demon) was due to a mutually eclipsing binary. Since then it has become clear that most stars are in binary or multiple star systems. This is most fortunate because the orbital motions can be used to obtain precise fundamental properties, such as the mass and brightness, and sometimes the radius of each star. The crown jewels of such systems for modeling purposes are double-lined spectroscopic and eclipsing binary stars that are located in star clusters that share a common age and chemical composition. That would be enough, but there is more! The evolution of the stars in a binary or trinary star system can be fundamentally altered by that proximity, and can lead to contact binaries, nova or supernova outbursts, and binary star mergers. The study of the end products of stellar evolution, such as red giants, white dwarfs, neutron stars, pulsars, and black holes is enhanced when they are in binary configurations. The merger of black hole binaries enabled the first discoveries of gravitational waves in 2015; the first G-Wave detection of a binary neutron star merger was confirmed by visual, IR, x-ray and (-ray observations in 2017.
Bio: Gene Milone received a BA from Columbia (1961) and an MS (1963) and PhD (1967) from Yale, after which he worked in the Rocket Spectroscopy Branch of the Naval Research Laboratory’s Space Science Division and taught at Gettysburg College in PA, developing their observatory. He came to the University of Calgary in 1971 in part to aid in the development of the Rothney Astrophysical Observatory which he co-directed with Alan Clark until the early 1990s; and retired as director in 2004. With colleagues, he aided in the design and construction of telescope systems, developed the Rapid Alternate Detection System to measure precisely the comparative brightness of stars even in light cloud conditions, developed and tested at the RAO an infrared passband system to enable precise infrared astronomy, and facilitated the acquisition of a new patrol camera for the study of variable stars and solar system minor bodies. He is a past president of the International Astronomical Union’s Photometry and Polarimetry Commission and past Chairperson of its Infrared Working Group.
We also wish to acknowledge the Department of Biological Sciences which has provided the venue