  As a legacy of the Hubble Space Telescope, a multi-cycle public survey has
recently been approved and began to scan an area of approximately 0.5 degrees x
1.5 degrees in one quadrant of M31, using two cameras and several filters. The
purpose of this work is to immediately release to the community a catalog of
the sources imaged by ACS/WFC. The list will be updated on an almost real-time
basis, as new data arrive, and the process will continue for the next two
years, until the survey is completed. Each update will contain a chunk of 1/46
of the entire ACS/WFC survey, by means of astrometrized stacked images, and a
catalog providing: positions, magnitudes, and several quality parameters.
