Deep submillimeter images of NGC 891 - Cold dust at larger galactic radii

We present images in the 450 and 850 mu m continuum of the edge-on galaxy N GC 891. These measurements, carried out with the recently commissioned Subm illimeter Common User Bolometer Array, provide the deepest images yet of a nearby galaxy in the submillimeter wave band. We detect dust emission from 2/3 of the optical disk and confirm the presence of dust chimneys escaping from the main absorption layer up to z-heights of nearly 2 kpc. A compariso n between the submillimeter surface brightness along the major axis with th at corresponding to the IRAS 60 and 100 mu m filters implies that large amo unts of cold dust (similar to 15 K) are present in the disk (in fact, an or der of magnitude more grain material than the warm dust detected by IRAS). These cold grains predominate at larger galactic radii.