Fig. 2: A linear feature in the spatial distribution of faint galaxies in the NGC 1052 field.
From: A trail of dark-matter-free galaxies from a bullet-dwarf collision
a, Distribution of galaxies with g > 16.5 (black circles) from a recent compilation of low-surface-brightness objects in the NGC 1052 field23. The positions are with respect to the coordinates of NGC 1052, the central bright elliptical galaxy in the group. b, Hough transform24 of the spatial distribution. The peak corresponds to a line that has 11 galaxies located within ±30 kpc. The significance of the feature, as determined from randomized realizations of the data, is 97%. c, Zoom of a, shown with the four brightest members of the NGC 1052 group. Yellow circles correspond to the positions of the galaxies in the box shown in a. The orientation and offset of the line corresponds to the location of the peak of the Hough transform. Both DF2 and DF4 are part of the linear feature.
