HuBi 1 has been proposed to be member of the rare class of born-again planetary nebulae (PNe), i.e., its central star experienced a very late thermal pulse and ejected highly-processed material at high speeds inside the old hydrogen-rich PN. In this letter we present GTC MEGARA integral field spectroscopic observations of the innermost regions of HuBi 1 at high spectral resolution $simeq16$ km s$^{-1}$ and multi-epoch sub-arcsec images obtained $simeq 12$ yr apart. The analysis of these data indicates that the inner regions of HuBi 1 were ejected $simeq200$ yr ago and expand at velocities $simeq300$ km s$^{-1}$, in excellent agreement with the born-again scenario. The unprecedented tomographic capabilities of the GTC MEGARA high-dispersion observations used here reveal that the ejecta in HuBi 1 has a shell-like structure, in contrast to the disrupted disk and jet morphology of the ejecta in other born-again PNe.
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