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M.D. Gregg (University of California, Davis), H.C. Ferguson (STScI), D. Minniti (P Universidad Catolica de Chile), N. Tanvir (University of Hertfordshire)
Using HST and NICMOS, we have obtained F110W (J) and F160W (H) images of three fields in the halo of NGC3379, the nearest giant elliptical galaxy (~10-12 Mpc). These data resolve the individual red giant stars, yielding the first color-magnitude diagram for a normal, large elliptical. The photometry reaches ~ 0.5 magnitude below the red giant branch tip with errors of 0.2~mags in H. By fitting theoretical isochrones, the metallicity is determined to be approximately one tenth solar. There is a substantial population of stars brighter than the RGB tip. By observing each field at two different epochs, we have identified candidate Mira variables. Lacking period determinations, the nature of these variables is uncertain. The bright AGB stars and variables suggest the presence of an intermediate age population, though a strictly old age cannot be ruled out.