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Arguments are presented which suggest that the unusual 'bright variables' observed in Draco and other dwarf spheroidals are more massive than the RR Lyrae variables in the same systems. Models of very metal-poor stars on the horizontal branch with masses up to 2 solar masses confirm this interpretation in the sense that both the luminosities and the period-luminosity relation of the models are consistent with the observations of the bright variables. Some implications of the presence of stars about one billion years old in dwarf spheroidal galaxies are briefly discussed.
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Demarque et al. (1975) studied this question.
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