Here is the full list of all 25 Interplanetary achievements.
Beat the Impossible AI.
Have 25,000 material in stock.
Unlock all technologies.
Fire Solar Laser superweapon.
Fire Asteroid Diversion superweapon.
Grow five cities to their maximum populations.
Have your planet run out of material.
Win an online multiplayer match with at least two players.
Win an online multiplayer match.
Defeat an enemy planet.
Produce 7,000 Energy in one turn.
Win 5 online multiplayer matches.
Win 10 online multiplayer matches.
Win 50 online multiplayer matches.
Win 100 online multiplayer matches.
Win 10 single player games.
Win 100 single player games.
Win an online multiplayer match with at least four players.
Win an online multiplayer match with eight players.
Destroy 100 cities over any number of games.
Defeat two enemy planets in one turn.
Build 200 buildings on your planet.
Hit your own planet with a railgun.
Win a match with barely any population left.
Fire all the superweapons during the same turn.