The Rayleigh-Taylor instability and the origin of filamentary structures in the Vela supernova remnant

The nature of the Vela X-ray ”jet”, recently discovered by Markwardt & Ögelman (1995), is examined. It is suggested that the ”jet” arises along the interface of domelike deformations of the Rayleigh-Taylor unstable shell of the Vela supernova remnant; thereby the ”jet” is interpreted as a part of the general shell of the remnant. The origin of deformations as well as the general structure of the remnant are discussed in the framework of a model based on a cavity explosion of a supernova star. It is suggested that the shell deformations viewed at various angles appear as filamentary structures visible throughout the Vela supernova remnant at radio, optical, and X-ray wavelengths. A possible origin of the nebula of hard Xray emission detected by Willmore et al. (1992) around the Vela pulsar is proposed.