The Warm Spitzer mission for the investigation of nearby galaxies

Spitzer in the warm phase will provide a unique opportunity for large-field and deep observations of nearby galaxies to address a number of fundamental science questions that cannot be adequately answered within the confines of current sample sizes/depths as produced by regular general observer, or even Legacy, proposals. Potential science goals include the morphological classification of galaxies, the investigation of the edges of galaxy disks and of intragroup/intracluster environments, the use of hot dust emission to trace star formation and AGNs, the: monitoring of supernovae and of other variable sources, and the calibration of stellar population models in the mid-IR. The local Universe is the only available benchmark against which distant galaxies can be compared, and every effort should be made to ensure that the properties of nearby galaxies are fully investigated by the 'warm' Spitzer.