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The ultra diffuse galaxies DF2 and DF4 in the NGC1052 group share several unusual propertiesdoublePoint they both have large sizes comma rich populations of overluminous and large globular clusters comma and very low velocity dispersions indiciating little or no dark matter. Recently it was found that DF2 and DF4 are very far apart along the line-of-sight comma have a high relative velocity comma and are part of a linear structure of 8-12 large comma unusual galaxies in the group. It has been proposed that DF2 comma DF4 comma and the other galaxies along the trail originated in the aftermath of a d_commabullet dwarf.. event comma a high speed collision between two galaxies virgul9 Gyr ago that separated gas from dark matter. Four of the galaxies in the trail have been imaged previously with ACS. Here we propose to image the other 8 galaxies in the trail. The immediate goals are to measure the globular cluster populations comma morphologies comma colors comma and surface brightness fluctuation distances of all the galaxies in this remarkable linear structure. These observations are critical for preparing follow-up spectroscopic and ultra deep HST imaging observations comma and lay the foundation for a constraint on the self-interaction cross section of dark matter on kpc scales.