In typical conditions, an electrical arc forms when the electric field strength exceeds the dielectric strength of the medium (like air). In a vacuum, there is no medium to ionize, which theoretically makes it difficult for an arc to form. However, electricity can still arc in a vacuum under certain conditions, such as when high voltages are involved or when the electrodes are extremely close together.
Well, noses can't taste very much is my guess so they are a lot better at smelling