M31, Andromeda Galaxy

2.5 million light-years (0.8 megaparsecs)

Data of M31 were obtained from the HST PHAT Treasury Proposals: P.I. J. Dalcanton (University of Washington) et al. 12055, 12056, 12057, 12058, 12059, 12076, 12070, 12071, 12072, 12073, 12074, 12075, 12114, 12105, 12106, 12107, 12108, 12109, 12111, 12112, 12113, 12114, and 12115.

F475W (g) and F814W (I)

NASA, ESA, J. Dalcanton, B.F. Williams, L.C. Johnson (University of Washington), the PHAT team, and R. Gendler

This image is a composite of separate exposures acquired by the ACS instrument on the Hubble Space Telescope. Several filters were used to sample broad wavelength ranges. The color results from assigning different hues (colors) to each monochromatic (grayscale) image associated with an individual filter. In this case, the assigned colors are:

Blue: F475W (g)
Yellow: F814W (I)