totality

Half-way through ingress by most estimates, but epsilon Aurigae continues to confound.  Middle of October, the star changed its rate of decline in brightness, from rapid to less rapid - see the visual light curve data link.  This change of slope seems to be more pronounced at shorter wavelengths, less pronounced at longer wavelengths.  Clues like these will help us define the nature of the eclipsing body more precisely.  If purely due to effective area, it says that the disk is slightly thinner-looking in bluer light, relative to red wavelengths.  Ultraviolet light curves during last eclipse seem consistent with this trend.Read more