Designer John HarshmanMarc W. Miller Publisher Steve Jackson Games Players 2-3 Playtime 45 mins Suggested Age 12 and up Additional Info 3637/triplanetary http://boardgamegeek.com/boardgame/3637/triplanetary/forums/63 Set in the 21st century, the map depicts the inner Solar system out to Jupiter. Scenarios involve racing, pirating, invasions, and a few others.Movement involves vector mechanics. Players plot courses using a grease pencil on the map and use fuel to accelerate a maximum of one each turn. Planets and moons are used to modify the trajectory.There are a limited number of ships. Most are limited in fuel, so making efficient use of gravity is important to reaching a destination.2nd edition came out in 1981. A 3rd edition was released in 2018 by Steve Jackson Games.It is fairly easy to extend the game to much more than 3 players, although the board can become cluttered with ship trails (the game is sorta like Crayon Rails in this respect).