ACS observations of Abell 1689

A1689 is one of the most powerful gravitational lenses in the sky. In June 2002 we observed the center of A1689 with the ACS WFC for 20 orbits in the g,r,i,z bands, plus 3 orbits of grism observations. The resulting images are close to the depth of the HDFN over an area of 3.4'x3.4'. Combined with the magnification from the cluster, this offers an unprecedented view of the high redshift universe. The multicolor coverage, complemented with extensive ground based observations allows us to obtain reliable photo-z for a large fraction of the galaxies in the field. We have identified several multiple arc systems, and in some cases have confirmed their redshifts with grism observations. We present our first results on the lensing analysis of this cluster.