%V 353 %L discovery17016 %T The role of non-gray model atmospheres in the evolution of low mass metal poor stars %C Tartu, ESTONIA %K THERMONUCLEAR REACTION-RATES, LINE LIST, STELLAR ATMOSPHERES, MOLECULAR OPACITIES, MAIN-SEQUENCE, INTENSITIES, STATE %A GJ Harris %A AE Lynas-Gray %A J Tennyson %A S Miller %E HJGLM Lamers %E N Langer %E T Nugis %E K Annuk %B Stellar Evolution at Low Metallicity: Mass Loss, Explosions, Cosmology %X Gray model atmospheres are generally considered a reasonable approximation to make upon stars of mass greater than about 0.6 M-circle dot. Here we show that non-gray atmospheres can significantly affect evolutionary models, with masses up to 0.9 M-circle dot. The effect of including a non-gray atmosphere is strongest in the pre-main and post-main Sequence. This may have implications for the ages of the oldest globular clusters. %I ASTRONOMICAL SOC PACIFIC %P 83 - 90 %D 2006