Continuous and highly variable emissions at 130.4 nm are observed on the night-side of Venus by the Pioneer Venus Orbiter ultraviolet spectrometer. The emissions have a typical intensity of 10--20 R, occasionally exceed 100 R, and have a dawn-dusk asymmetry in brightness during periods of unusual intensity. A possible energy source for this ''aurora'' is the precipitation of suprathermal electrons. Field and particle observations suggest an additional source for the brightness emissions which is associated with solar flares and/or interplanetary shocks.