In Atari’s 1979 arcade game Asteroids, what happens when a large asteroid is shot?

In Atari’s 1979 arcade game Asteroids, shooting a large asteroid splits it into smaller asteroids.

The player controls a rotating spaceship in a wraparound field filled with drifting rocks. Large asteroids break into medium asteroids, and medium asteroids break into small asteroids. The smaller pieces are worth fewer points individually, but they increase the number of objects the player must avoid.

This splitting mechanic distinguishes Asteroids from a simple target-shooting game. The player can rotate, thrust, fire, and use hyperspace while managing momentum. Asteroids was designed by Lyle Rains and Ed Logg, and its vector display produced bright lines rather than filled bitmap shapes. The game became one of Atari’s best-known arcade successes.