A Cepheid Distance to the Fornax Cluster

B. F. Madore; W. L. Freedman; N. Silbermann; P. Harding; J. Huchra; J. R. Mould; J. A. Graham; L. Ferrerase; B. K. Gibson; M. Han; J. G. Hoessel; S. M. Hughes; G. D. Illingworth; R. Phelps; S. Sakai; P. Stetson

arXiv · astro-ph/9809059

A Cepheid Distance to the Fornax Cluster

B. F. Madore·W. L. Freedman·N. Silbermann·P. Harding·J. Huchra·J. R. Mould·J. A. Graham·L. Ferrerase·B. K. Gibson·M. Han·J. G. Hoessel·S. M. Hughes·G. D. Illingworth·R. Phelps·S. Sakai·P. Stetson

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Abstract

The Hubble Space Telescope is being used to measure accurate Cepheid distances to nearby galaxies with the ultimate aim of determining the Hubble constant, H_0. For the first time, it has become feasible to use Cepheid variables to derive a distance to a galaxy in the southern hemisphere cluster of Fornax. Based on the discovery of 37 Cepheids in the Fornax galaxy NGC 1365, a distance to this galaxy of 18.6 +/- 0.6 Mpc (statistical error only) is obtained. This distance leads to a value of H_0 = 70 +/- 7 (random) +/- 18 (systematic) km/sec/Mpc in good agreement with estimates of the Hubble constant further afield.

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B. F. Madore, W. L. Freedman, N. Silbermann, P. Harding, J. Huchra, J. R. Mould, J. A. Graham, L. Ferrerase, B. K. Gibson, M. Han, J. G. Hoessel, S. M. Hughes, G. D. Illingworth, R. Phelps, S. Sakai, P. Stetson. 1998-09-04. A Cepheid Distance to the Fornax Cluster. https://arxiv.org/abs/astro-ph/9809059

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