Here are two interacting galaxies that lie over 200 million ly away down in the constellation Indus. NGC6935 is on the left, and NGC6937 on the right. Note that both have inner arms formed into rectangular box-like shapes.

The interaction between the two is demonstrated by the extra (3rd) arm of NGC6937. Note that it appears to be pulled toward the denser, fortress-like NGC6935,
and is elevated above one of the main arms.

PlaneWave 12.5″ Astrograph with a ZWO ASI 6200 camera, Astrodon filters,and ASA gearless DDM-85 mount. F/8 LRGB (37/8min L, 12/8min RGB each, all 2×2 bin).