The game is a typical Moon-game where everything evolves around a deck of cards. Each player begins with a marker on each planet, a number back on Earth, two special Transport cards and a hand of 9 cards. Especially the latter option is very useful in the endgame. The heart of the game is the unique trading system. The cards depics one of the 7 planets, and you want to collect series of 3 or more cards in order to make your actions.
Players trade by placing cards on the table and there is no negotiating involved.
Only rule to obey is that no player may offer the same cards as the Start player. After trading, players have two actions - or three if you are the Start player. Most actions involve handing in sets of at least 3 but often more identical cards. The heart of the game are the Mining Rights to the 3 small satellites around each planet. These are worth from 4 to 14 points at the end of the game.