Here is the full list of all 23 Space Farmers achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Got to the end of the game with no deaths.
Killed more chompys than your friend in a game.
Unlocked Franky in Attack Of The Vegtabots
Killed 500 chompys
Made it through 'Pig Weapon' with one set of gloves.
Escaped The Extreme Grinder
Made it through Bomb Hats without collecting all the clocks.
Killed 3 chompys at once with potato bombs
Didn't let the Pieosaurus die.
Killed all the soldier bots in Cross Fire
Carried the pig 1000 metres
Found the funny face mask.
Did all the challenges in 1 run
Made it through The Grind without getting the weapons.
Found the final piggy.
Made it through the discotheque.
Got killed by a mine when not wearing the goggles in Helpful Chums
Played as another character.
Spent some turnips.
Complete all the challenges
Killed 100 chompys
Made it to the end of game party
Escaped The Grinder