We propose to investigate the resolved variations of the dust abundance and properties within and between galaxies in the nearby universe to inform chemical evolution models, constrain dust…

The National Aeronautics and Space Administration (NASA) awarded a $435,149.24 grant to the Association of Universities for Research in Astronomy, Inc. (AURA), doing business as the Space Telescope Science Institute (STScI), to investigate the resolved variations of dust abundance and properties within and between nearby galaxies. The goal is to inform chemical evolution models, constrain dust formation and destruction processes, and improve dust and gas mass estimates in the distant universe. The research will anchor archival Spitzer and Herschel observations to previous all-sky observations to account for diffuse dust emission, improving the calibration and legacy value of these space telescope data products. The project will derive maps of dust surface density, properties, and abundance in nearby galaxies, which will be made publicly available. This grant does not have a set-aside designation. AURA, a non-profit organization that manages and operates major astronomical observatories and telescopes, frequently collaborates with subcontractors on NASA's space telescope missions and receives grants to conduct cutting-edge astrophysics research.

We propose to investigate the resolved variations of the dust abundance and properties within and between galaxies in the nearby universe to inform chemical evolution models, constrain dust formation and destruction processes and timescales, and improve dust and gas mass estimates in the distant universe. We will first anchor archival spitzer and herschel observations of nearby galaxies to previous all-sky observations with iras, cobe/dirbe, and planck to account for diffuse dust emission not detected in spitzer and herschel due to the nature of those measurements. We will thus considerably improve the calibration and legacy value of herschel and spitzer science products. We will apply an existing dust model to the spectral energy distribution (SED) in the improved spitzer and herschel data products, and derive maps of the dust surface density, properties, and abundance in nearby galaxies, which will be made publicly available. Because faint dust emission is not detected in individual pixels, we will also use a stacking analysis to measure how the dust surface density and abundance (gas-to-dust ratio, g/d) vary with gas surface density over the whole surface density range of the ISM, including the very diffuse ISM (?gas