Alien

Alien, in the context of Conway's Game of Life, denotes concepts not related (i.e. alien) to Conway Life. The term is primarily applied to rules (cellular automata) and patterns. An alien rule is any cellular automaton other than Conway Life itself; an alien pattern or alien object (sometimes shortened to "an alien") is a pattern or object not existing, or behaving differently, in Conway Life.

Examples

Day & Night (B3678/S34678) is an alien rule; the fireball, a period-40 spaceship in Day & Night, is an alien spaceship:

x = 11, y = 51, rule = B3678/S34678 6bo$6b2o2$8bo$5bo2bo$5b3o9$3bo$3bo$b3obob2o$ob3ob2obo$ob7o$b9o$3b7o$ 11o$obob5obo$2b6obo$bob4obo$3b6o$3b5o$3b2o$2b2o$3b2ob2o$3b2obo$4b3o$ob ob2obo$o2b5o$2b4obo$ob4o$b6o$2b4o$2b4obo$3b4ob2o$3b7o$4b5o$3b7o$11o$ 11o$b9o$8o$b8o$2b6o$3b4o$4b2o! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ AUTOSTART TRACKLOOP 40 0 1/2 GPS 20 THUMBSIZE 2 ZOOM 8 WIDTH 480 HEIGHT 480 ]]

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