This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
DayNightButterflyGun. Period butterfly gun in the Day Night cellular automaton This pattern was first constructed by David Bell in Image created using the sourceforge net Golly opensource cellular automaton simulator en David Eppstein en David Eppstein original upload log page en DayNightButterflyGun David Eppstein bytes