Approximately Up

1. 
   Tutorial Completed

   Successfully complete the tutorial.
   86%
2. 
   Baaa-ck To Headquarters

   Bring tutorial sheep to Headquarters.
   4.3%
3. 
   The Long Way Home

   Complete the journey.
   0.2%
4. 
   When The Thrusters Go Quiet

   Complete every available objective.
   0.1%
5. 
   One Step Further

   Discover a new planet.
   54%
6. 
   First Milestone

   Complete your first objective.
   69%
7. 
   Event Horizon

   Travel through a Black Hole Tunnel to a new universe.
   0.7%
8. 
   Jurassic Surprise

   Encounter a dinosaur.
   0.8%
9. 
   Solar Storm

   Encounter a solar storm.
   19%
10. 
    Edge Of The Known

    Find Tenebra, the farthest known planet.
    0.4%
11. 
    Way Forward

    Activate a Black Hole Tunnel.
    0.9%
12. 
    Saving The Twins

    Prevent a planetary catastrophe.
    0.3%
13. 
    Houston, We Have A Submarine

    Reach a depth of 1000m below sea level.
    22%
14. 
    Need For Thrust

    Reach a speed of 1 000 000 m/s.
    0.4%
15. 
    Green Trench

    Reach bottom of Green Trench.
    2.8%
16. 
    No Rewinds!

    Complete the objective without using Time Rewind.
    56%
17. 
    Golden Thruster

    Complete every objective without using Time Rewind.
    0.0%
18. 
    See You Next Week

    Travel safely from Aundara to Outcast, or from Outcast to Aundara.
    0.1%
19. 
    Wool Age

    Transport a sheep from Earth to the Moon alive, then release her into the wild.
    2.0%
20. 
    Ice Age

    Transport a mastodon from the Moon to Earth alive, then release him into the wild.
    1.5%
21. 
    Almost Crispy

    Get within 1 000 000 meters of the Sun and survive.
    0.2%
22. 
    Small But Spicy

    Get within 100 000 meters of the Red Dwarf and survive.
    0.2%

Names, descriptions and icons are the game’s own, as Steam publishes them; the share is how many owners have unlocked each, from Steam's global figures for 22 of them.