These examples of interacting galaxy pairs — clockwise from upper left, NGC 5394/5, NGC 2623, NGC 3921, and NGC 6052 — show how the process of merging destroys their spiral structures.

clockwise from upper left: International Gemini Observatory/NOIRLab/NSF/AURA; ESA/Hubble & NASA; ESA/Hubble & NASA; ESA/Hubble & NASA, A. Adamo et al.