Analysing a Variable Star – from observations to physical model.

Affiliation(s): ASV, VSS

Session details: Saturday, 2012-04-07 04:15:00, TBA

Abstract

Observing the changes in brightness of a variable is the essential first stage in finding out what it is like astrophysically. In this talk I will take as an example CU Hydrae, an eclipsing binary that had hardly ever been looked at since its discovery in 1936. In 2010 and 2011 it was observed using CCD-equipped telescopes by a number of VSS and BAA observers in a joint project. This presentation will describe the journey from those observations, building a light curve out of them, finding period changes over the years and what that signifies, working out what sort of stars make up the binary – masses, luminosities, orbits, shapes, and finally building a 3D model of the system.

Biography

Tom’s primary research interest is variable stars, in particular eclipsing binaries. In 2009 he was appointed Director of the Variable Star Section of the RASNZ, now called Variable Stars South. Tom was awarded the Murray Geddes Prize of the Royal Astronomical Society of NZ in 1959 and the Berenice Page Medal of the Astronomical Society of Australia in 2006, for his research work as an amateur astronomer. He is a past president of the Astronomical Society of Victoria.