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We present a proper motion measurement of Vela pulsar of $\sim~100$~km~sec$^{-1}$ to the northwest, based on several brief Hubble Space Telescope WF/PC exposures. This confirms previous measurements using ground-based optical and radio interferometric techniques (\"Ogelman et al , 1989, ApJL , 342 , L83; Bailes et al , 1990, MN , 247 , 322). Direct comparison between the HST images and Lasker's ``discovery'' plate clearly shows the pulsar diplacement over 18~years. Consequences of this finding will be discussed.
A presentation of diffuse structure surrounding the pulsar will also be made. While the HST exposures were too short to unveil significant sub-arcsecond details, coarse results can be obtained after subtraction of stellar components from the image.