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The planetary nebula (PN) called the Stingray (PN G331.3$-$12.1) suddenlyturned on in the 1980s, and its central star (V839 Ara) started a fastevolution with large amplitudes in magnitude, surface temperature, and surfacegravity, perhaps as part of a late thermal pulse causing a loop in theHertzsprung-Russell (HR) diagram. With these fast changes, we have taken imageswith the Hubble Space Telescope in 2016. We do not see the massivehigh-velocity mass loss of the 1980s, either close in to the central star, oras clumps or changes in the nebula far from the star, or as localized orgeneral increases in the emission-line flux caused by the shocks of theoutflowing ejecta ramming into the slow-moving PN shell. We think that the lackof seeing the outgoing material is because the relatively modest total mass hadalready suffused the PN before the first resolved imaging in 1992, and it wasthe shocks from this impact that initially ionized the Stingray starting in the1980s. We also quantify the complex fast fading of the Stingray, with eachemission line and each structure having different fade rates, with half-livesranging from 3 to 29 years. In a century or two, the PN will fade toinvisibility. With this complex fading of different structures, it isimpossible to derive any expansion rate for the PN. The central star had itsbrightness roughly constant from 1996 to 2016, but with substantial erraticvariability from 15.50 to 14.18 mag in the $V$ band.

Startlingly Fast Evolution of the Stingray Planetary Nebula and its Central Star, V839 Arae