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We report the detection of vertically extended far-ultraviolet (FUV) and near-UV emissions in an edge-on spiral galaxy NGC 891, which we interpret as being due to dust-scattered starlight. Three-dimensional radiative transfer models are used to investigate the content of the extraplanar dust that is required to explain the UV emission. The UV halos are well reproduced by a radiative transfer model with two exponential dust disks, one with a scaleheight of ≈ 0.2 − 0.25 kpc and the other with a scaleheight of ≈ 1.2 − 2.0 kpc. The central face-on optical depth of the geometrically thick disk is found to be τ thick B ≈ 0.3 − 0.5 at B-band. The results indicate that the dust mass at |z| > 2 kpc is ≈ 3 − 5% of the total dust mass, which accord well with the recent Herschel sub-millimeter observation. Our results, together with the recent discovery of the UV halos in other edge-on galaxies, suggest the widespread existence of the geometrically thick dust layer above the galactic plane in spirals.

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We present far-ultraviolet observations of the Antlia supernova remnant obtained with Far-ultraviolet IMaging Spectrograph (FIMS, also called SPEAR). The strongest lines observed are C IV λλ1548,1551 and C III λ977. The C IV emission of this mixed-morphology supernova remnant shows a clumpy distribution, and the line intensity is nearly constant with radius. The C III λ977 line, though too weak to be mapped over the whole remnant, is shown to vary radially. The line intensity peaks at about half the radius, and drops at the edge of the remnant. Both the clumpy distribution of C IV and the rise in the C IV to C III ratio towards the edge suggest that central emission is from evaporating cloudlets rather than thermal conduction in a more uniform, dense medium.