Re: [vsnet-chat 3861] KR Mus > I noticed that KR Mus is classified as a planetary nebula in some > references. The variable star designation was given from the supposed > classification as an eclipsing variable from Hipparcos photometry. > Is this a rare "eclipsing PN nucleus" or of a different type? I have learned that KR Mus is usually regarderd as a Herbig Ae/Be star. It is quite likely "eclipses" observed by Hipparcos were transient fading episodes of this class of objects. A question remains. Where did the SIMBAD "planetary nebula" classification come from? Regards, Taichi Kato