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arXiv · astro-ph/0601599

Andromeda X, A New Dwarf Spheroidal Satellite of M31: Photometry

Daniel B. Zucker·Alexei Y. Kniazev·David Martinez-Delgado·Eric F. Bell·Hans-Walter Rix·Eva K. Grebel·Jon A. Holtzman·Rene A. M. Walterbos·Constance M. Rockosi·Donald G. York·J. C. Barentine·Howard Brewington·J. Brinkmann·Michael Harvanek·S. J. Kleinman·Jurek Krzesinski·Dan Long·Eric H. Neilsen, Jr.·Atsuko Nitta·Stephanie A. Snedden
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Abstract

We report the discovery of Andromeda X, a new dwarf spheroidal satellite of M31, based on stellar photometry from the Sloan Digital Sky Survey (SDSS). Using follow-up imaging data we have estimated its distance and other physical properties. We find that Andromeda X has a dereddened central surface brightness of mu_V,0 ~ 26.7 mag arcsec^-2 and a total apparent magnitude of V_tot ~ 16.1, which at the derived distance modulus, (m - M)_0 ~ 24.12 - 24.34, yields an absolute magnitude of M_V ~ -8.1 +/- 0.5; these values are quite comparable to those of Andromeda IX, a previously-discovered low luminosity M31 satellite. The discoveries of Andromeda IX and Andromeda X suggest that such extremely faint satellites may be plentiful in the Local Group.

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Daniel B. Zucker, Alexei Y. Kniazev, David Martinez-Delgado, Eric F. Bell, Hans-Walter Rix, Eva K. Grebel, Jon A. Holtzman, Rene A. M. Walterbos, Constance M. Rockosi, Donald G. York, J. C. Barentine, Howard Brewington, J. Brinkmann, Michael Harvanek, S. J. Kleinman, Jurek Krzesinski, Dan Long, Eric H. Neilsen, Jr., Atsuko Nitta, Stephanie A. Snedden. 2006-01-26. Andromeda X, A New Dwarf Spheroidal Satellite of M31: Photometry. https://doi.org/10.1086/516748

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