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We present an absolute parallax and relative proper motion for the centralstar of the planetary nebula NGC 6853 (The Dumbell). We obtain these withastrometric data from FGS 3, a white-light interferometer on {\it HST}.Spectral classifications and VRIJHKT$_2$M and DDO51 photometry of the starscomprising the astrometric reference frame provide spectrophotometric estimatesof their absolute parallaxes. Introducing these into our model as observationswith error, we find $\pi_{abs} = 2.10 \pm 0.48$ mas for the DAO central star ofNGC 6853. A weighted average with a previous ground-based USNO determinationyields $\pi_{abs} = 2.40 \pm 0.32$. We assume that the extinction suffered bythe reference stars nearest (in angular separation and distance) to the centralstar is the same as for the central star. Correcting for color differences, wefind $<$A$_V>$ = 0.30 $ \pm $ 0.06 for the central star, hence, an absolutemagnitude M$_V = 5.48^{-0.16}_{+0.15}$. A recent determination of the centralstar effective temperature aided in estimating the central star radius,$R_{*}=0.055 \pm 0.02R_{\sun}$, a star that may be descending to the whitedwarf cooling track.Comment: To appear in The Astronomical Journal, November 2003. CS absolute  position (Table 2) changed to 2MASS positio

Astrometry with TheHubble Space Telescope: A Parallax of the Central Star of the Planetary Nebula NGC 6853