A Study of an Eclipsing Variable
A small percentage of stars vary in brightness periodically. So far over 100,000 have been catalogued. An important class of variable stars are the eclipsing variables. These are binary star systems whose orbital plane is orientated in such a way that each star is totally or partially eclipsed by the other during the orbital period. Well-known types include Algol variables, Beta Lyrae stars and W Ursae Majoris stars.
The aim of the project is to determine the light curve and hence the period of an eclipsing variable. By choosing variable stars with adjacent non-varying stars the light curve can be easily determined from measurements of the relative brightness. How well can the light curve and period be determined? Using archival and published data for this system is there any evidence for a change of period?
The eclipsing variable CW Cas has a period of 7.6 hours. The light curve below was measured by Astrolab students ( Jennifer and Victoria).