Spitzer Survey of Stellar Structure in Galaxies (S4G)

The Spitzer Survey of Stellar Structure in Galaxies (S4G) is a volume-, magnitude-, and size-limited survey of over 2300 nearby galaxies at 3.6 and 4.5μm. This is an extremely deep survey reaching an unprecedented 1σ surface brightness limit of μ3.6μm(AB) = 27 mag arcsec-2. This translates to a stellar surface density of << 1 M⊙ pc-2 ! S4G can thus probe the stellar structure in galaxies in a regime where the gas dominates the stars (typical HI surface density ~ a few M⊙ pc-2). This dataset or service is made available by the Infrared Science Archive (IRSA) at IPAC, which is operated by the California Institute of Technology under contract with the National Aeronautics and Space Administration.