Mission Asteroid is a graphic adventure game for the Apple II written by Ken and Roberta Williams and released in 1980 by On-Line Systems, now known as Sierra Entertainment. It was later ported to the Atari 8-bit family and Commodore 64.
The game was released as Hi-Res Adventures #0, despite being released after Mystery House and Wizard and the Princess. It was meant as an introduction to the adventure game genre so it was made easier than the rest of Hi-Res Adventures games and was given a lower number as a result.