Guns

Gosper glider gun

The first known finite pattern with unbounded growth.

The Gosper glider gun changed the status of Life by proving that a finite pattern can emit an infinite stream of moving objects.

Gosper glider gun has period 30

The Gosper glider gun is a 36-cell pattern in a 36 x 9 bounding box. Its core repeats every 30 generations while a glider escapes, which is why it is the classic first example of a finite pattern with unbounded growth.

Guns36 cells36 x 9 boxperiod 30
Category
Guns
Period
30
Movement
bounded
Population
36 cells
Bounding box
36 x 9
Known since
1970

Live pattern

Run Gosper glider gun here

Start with the canonical seed, step through individual generations, adjust speed, or edit cells on the board without leaving this page.

Simulation status

Generations0
Live cells32
Period30

What to watch

  • A new glider leaves the gun every 30 generations.
  • The two stable blocks act as eater-like boundary objects.
  • The central reaction repeats instead of burning out.

How to use it

Use it to introduce glider streams, guns, and unbounded population growth.

Open the pattern in the lab, reduce the speed, and use single-step mode when a phase change is hard to see. The green preview marks births in the next generation; red outlines mark live cells that will die.

Fast answers

Common questions about Gosper glider gun

What is the period of the Gosper glider gun?

The period is 30. After 30 generations, the gun core returns to the same phase while a glider has moved away.

How large is the Gosper glider gun?

The standard pattern has 36 live cells in a 36 x 9 bounding box.

Why does the Gosper glider gun prove Life can grow forever?

It starts from a finite pattern and keeps emitting gliders under the standard B3/S23 rule, so the live-cell history is unbounded rather than settling into final ash.