From the Game's Introduction:
Adventures in Space!! is a game of thrilling space stories. It is best played with three to six players, one acting as Space Command and the rest as Players. Space Command acts to provide challenges and move the story along. Players not only face these challenges with a courageous heart, but often improvise and alter the course of the story!
To play all you need are a few six-sided dice and some pieces of paper (referred to here as Playsheets). Make sure one of your dice is different from the rest, as this one becomes your Die of Science! A dictionary or space-age comics might also help you to pick fitting Words of Science.