SY Muscae

SY Muscae is the first of three symbiotic stars we'll highlight over the next few weeks.  SY Mus is a fine southern Z Andromedae variable although we have yet to observe any outbursts of this star.  It does however show the familiar wave-like variation in the light curve.  As Skopal explained in his JAAVSO review, the variation originates from the irradiated wind coming from the system, rather than an eclipse of one of the bodies or from a reflection of light from the primary white dwarf off of the secondary.  While the variation has the same period as the orbit, it is caused by our changing viewing angle of the nebula that fills the system.