| Issue |
EAS Publications Series
Volume 48, 2011
CRAL-2010 A Universe of Dwarf Galaxies
|
|
|---|---|---|
| Page(s) | 61 - 62 | |
| Section | Star Formation History and Chemical Enrichment | |
| DOI | https://doi.org/10.1051/eas/1148010 | |
| Published online | 11 July 2011 | |
M. Koleva, Ph. Prugniel and I. Vauglin (eds)
EAS Publications Series, 48 (2011) 61–62
Discovery of RR Lyrae Stars in the Sculptor Group Dwarf Galaxies
1 European Southern Observatory, Karl-Schwarzschild-Strasse 2, 85748 Garching b. München, Germany
2 Research School of Astronomy & Astrophysics, Institute of Advanced Studies, Australian National University, Cotter Road, Weston Creek, ACT 2611, Australia
3 Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchofstrasse 12-14, 69120 Heidelberg, Germany
We report on discovery of first unambiguous evidence of the presence of ancient stars in galaxies beyond the Local Group. In two Sculptor Group galaxies, ESO 294-010 and ESO 410-005, we have used deep multi-epoch Hubble Space Telescope ACS observations to image stellar populations fainter than the horizontal branch magnitude. In both galaxies we uncovered a well populated blue horizontal branch, as well as numerous RR Lyrae variable stars. The presence of these low mass star testifies that the star formation in dwarf galaxies started at least 10 Gyr ago.
© EAS, EDP Sciences, 2011