van de Steene, G. C. ; Jacoby, G. H. ; Praet, C. ; Ciardullo, R. ; Dejonghe, H.

published in Astronomy and Astrophysics, 455, pp. 891-896 (2006)

Abstract: We analysed [O III], Hα, and continuum images of the Sculptor Group spiral galaxy NGC 55 obtained with the WFI instrument at the 2.2-m telescope of ESO. We identified 21 new planetary nebula candidates. We constructed the [O III]λ5007 Planetary Nebula Luminosity Function (PNLF) and determined a most likely distance of 2.30 ± 0.35 Mpc. The distance to NGC 55 is a bit larger than previously determined distances, which means that the Sculptor Group is further away from the Local Group than previously thought. The PNLF distance to NGC 55 is comparable to the PNLF distance of NGC 300 (Soffner et al. 1996, A, 306, 9), adding support to the suggestion that these galaxies form a bound pair. There doesn't seem to be a shortage of planetary nebula candidates in this metal poor galaxy.

DOI: 10.1051/0004-6361:20053475
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