FAR-INFRARED CONSTRAINTS ON STRUCTURE AND VARIABILITY OF SSV-13 IN NGC-1333

We report on a variety of observations of SSV 13 in NGC 1333 in the fa r-infrared. We have obtained photometry of the object at a number of t imes between 1981 and 1995, spanning the time over which the object br ightened by about 1 mag in the near-infrared. In addition, we report o n diffraction-limited scanning at 47 and 95 mu m. We find that the sou rce has brightened by a factor of 1.5-2 in the far-infrared over the p eriod of our observations, implying that the object has undergone a tr ue luminosity increase since most of the luminosity of this object is emitted in the far-infrared. This also implies that the far-infrared e mission is almost certainly associated with SSV 13, rather than the VL A source found recently about 7 '' southwest of SSV 13. Our spatial ob servations and the overall energy distribution of SSV 13 can be modele d successfully with a spherically symmetric dust distribution with a d ust optical depth of 0.3 at 100 mu m and a density gradient of r(-1.2/-0.2).