A 2-COMPONENT INFRARED NEBULA AROUND HR CAR

We present mid-infrared imaging of the LBV HR Car and its surrounding nebula. The 10 mu m broad-band N image reveals a geometry which is not point symmetric with respect to the central star on an arcsecond scal e. The 12.8 mu m narrow-band [Ne II] image shows a clumpy structure wh ich does not follow the N-band distribution. In addition, we detect a faint and probably clumpy outer nebula about 15 '' across. The morphol ogy of the infrared nebula and in particular its asymmetry is not at a ll in agreement with the large-scale structures as seen in optical ima ges. Three different episodes of shell ejection can now be distinguish ed for HR Car: the are-like structures seen in the optical, about 35 ' ' across, the faint IR nebula seen in the N-band, about 15 '' across, and the small, irregular nebula less than 8 '' across. The main conclu sion we draw from this is that the geometry of mass-ejections in HR Ca r is highly time-dependent and that multiple shell ejections can occur in LBVs. The distance of the small IR nebula from the central star ca n be well explained by a dust shell that is composed of silicates and is in radiative equilibrium with the central star.